[1] Szajewska H, Konarska Z, Kolodziej M. (2016). Probiotic Bacterial and Fungal Strains: Claims with Evidence. Dig Dis. 34(3):251-259. PMID: 27028756 Why chosen: This is a 2016 review that sorts probiotic strains by which claims actually have evidence behind them. I use it for two things: the general point that LGG strengthens the gut barrier and shifts immune signaling, and the narrower point that RCTs show benefit in high-risk groups. It is a review, so it carries no new data of its own. Its value here is triage, since Szajewska is one of the stricter voices in this field and a claim she keeps is more likely to hold up.

[2] Kankainen M, Paulin L, Tynkkynen S, et al. (2009). Comparative genomic analysis of Lactobacillus rhamnosus GG reveals pili containing a human-mucus binding protein. Proc Natl Acad Sci U S A. 106(40):17193-17198. PMID: 19805152 Why chosen: This is the 2009 genome paper for LGG, a comparative study rather than a trial. It does three jobs here: it backs the 46.8% GC content in the Biology section, it supports the contrast that other L. rhamnosus strains lack LGG’s mucus-binding pili, and it is one of two sources for the roughly one-day shortening of childhood infectious diarrhea. That last claim really rests on the meta-analyses underneath it. I keep this paper as the strain-characterization source rather than the outcome evidence.

[3] Reunanen J, von Ossowski I, Hendrickx AP, et al. (2012). Characterization of the SpaCBA pilus fibers in the probiotic Lactobacillus rhamnosus GG. Appl Environ Microbiol. 78(7):2337-2344. PMID: 22247175 Why chosen: This is a 2012 characterization study of the SpaCBA pilus fibers on the LGG surface. It is the source for the central mechanism claim: LGG grabs the gut wall with these pili, and that grip helps it stay longer. The work is bench science rather than a human trial. It explains how the strain might act and says nothing about whether patients improve.

[4] van den Akker CHP, van Goudoever JB, Shamir R, et al. (2020). Probiotics and Preterm Infants: A Position Paper by ESPGHAN. J Pediatr Gastroenterol Nutr. 70(5):664-680. PMID: 32332478 Why chosen: This is a 2020 position paper from ESPGHAN, the European pediatric gastroenterology group. It carries the strongest statement in the entry, because a guideline committee weighed the trials and gave LGG a conditional recommendation for preventing necrotizing enterocolitis in preterm infants. Conditional is the weaker grade, meaning the committee saw real but not conclusive benefit. I use it as an outside check on my own reading of the trial evidence.

[5] Zemla M, Kotowska-Babol M, Szajewska H. (2026). An update on probiotics in paediatrics. Curr Opin Clin Nutr Metab Care. 29(3):320-326. PMID: 41334956 Why chosen: This is a 2026 review of probiotics in children, co-authored by Szajewska. I use it alongside reference 1 for the antibiotic-associated diarrhea claim, which both trace back to RCTs and multiple meta-analyses. It is a review, so the numbers come from the trials underneath it. Its job here is currency: it is the most recent source in the entry and confirms the claim still stands.

[6] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus… Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: This is the 2020 paper that broke the genus Lactobacillus apart and described 23 new genera. I cite it for one fact only, that LGG moved to Lacticaseibacillus rhamnosus that year. The naming matters because older papers call it Lactobacillus rhamnosus GG, and a reader searching the old name will miss the new literature. It contains no clinical data.

[7] Pace F, Pace M, Quartarone G. (2015). “Probiotics in digestive diseases: focus on Lactobacillus GG.” Minerva Gastroenterol Dietol. 61(4):251-263. PMID: 26657927 Why chosen: This is a 2015 review focused on LGG in digestive disease. I take one thing from it, the historical detail that Gorbach and Goldin isolated the strain. A review is a fair place to source that kind of background, and I did not want to cite a primary paper I had not read for such a small point. It adds no outcome evidence to the entry.

[1] Takeda K, Suzuki T, Shimada SI, Shida K, Nanno M, Okumura K. (2006). Interleukin-12 is involved in the enhancement of human natural killer cell activity by Lactobacillus casei Shirota. Clin Exp Immunol. 146(1):109-115. PMID: 16968405 Why chosen: This is a 2006 randomized controlled trial, and it is the backbone of the Mechanism section. It shows LcS pushes monocytes to release IL-12, which then raises natural killer cell activity in people. The part I find most useful is the blocking step: when the researchers neutralized IL-12, the effect vanished, which ties the result to that one pathway. The trial measures immune markers rather than illness, so it shows the strain does something measurable in humans and stops there.

[2] Shida K, Sato T, Iizuka R, Hoshi R, Watanabe O, Igarashi T, Miyazaki K, Nanno M, Ishikawa F. (2017). Daily intake of fermented milk with Lactobacillus casei strain Shirota reduces the incidence and duration of upper respiratory tract infections in healthy middle-aged office workers. Eur J Nutr. 56(1):45-53. PMID: 26419583 Why chosen: This is a 2017 randomized controlled trial in healthy middle-aged office workers. The entry uses it for the duration finding, that LcS shortened how long each respiratory episode lasted. The paper also reports fewer infections, which matters to me directly given my own chronic rhinitis. It is one trial in one narrow population, so I treat it as supportive rather than decisive.

[3] Dong H, Rowland I, Thomas LV, Yaqoob P. (2013). Immunomodulatory effects of a probiotic drink containing Lactobacillus casei Shirota in healthy older volunteers. Eur J Nutr. 52(8):1853-1863. PMID: 23307112 Why chosen: This is a 2013 randomized controlled trial in healthy older volunteers. I cite it twice, in the Overview as part of the human RCT base for immune modulation and respiratory infection, and in Health benefit for the specific shift toward anti-inflammatory cytokines with a higher IL-10 to IL-12 ratio. Older adults are a group where immune function declines, so a measurable shift there carries some weight. The trial still measures markers rather than hard clinical endpoints.

[4] Reale M, Boscolo P, Bellante V, Tarantelli C, Di Nicola M, Forcella L, Li Q, Morimoto K, Muraro R. (2012). Daily intake of Lactobacillus casei Shirota increases natural killer cell activity in smokers. Br J Nutr. 108(2):308-314. PMID: 22142891 Why chosen: This is a 2012 randomized controlled trial in smokers. Three weeks of LcS raised natural killer cell killing activity and CD16+ cell counts, with P<0.001. I include it because it repeats the NK finding from reference 1 in a different population. Smokers are a specific group, so the result does not automatically carry over to everyone else.

[5] Maslennikov R, Gosteeva E, Ananeva V, et al. (2026). Strain-Specific Systematic Review with Meta-Analysis of Probiotics Efficacy in the Treatment of Irritable Bowel Syndrome. J Clin Med. 15(3):1152. PMID: 41682832 Why chosen: This is a 2026 strain-specific systematic review with meta-analysis of probiotics for irritable bowel syndrome. It is the strongest single source in this entry, because pooling trials beats any one trial. It found LcS helps overall IBS symptoms. The strain-specific design is why I trust it, since many probiotic meta-analyses lump strains together and hide the fact that effects are strain-specific.

[6] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus… Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The same 2020 taxonomy paper used across this document, here for the rename of LcS to Lacticaseibacillus casei. I repeat it in each entry so every strain carries its own naming note. No clinical data here.

[1] Altermann E, Russell WM, Azcarate-Peril MA, et al. (2005). Complete genome sequence of the probiotic lactic acid bacterium Lactobacillus acidophilus NCFM. Proc Natl Acad Sci U S A. 102(11):3906-3912. PMID: 15671160 Why chosen: This is the 2005 genome sequence paper for NCFM. It supplies the hard biological numbers in the entry, 1,864 predicted genes and GC content around 34.7%. It is also the source for the mechanism point that the SlpA surface protein drives adhesion to cells. A genome tells you what a strain is equipped to do and gives no result in a patient, so I keep it in Biology and Mechanism and out of the stronger health claims.

[2] Shen S, Ren F, Qin H, et al. (2023). Lactobacillus acidophilus NCFM and Lactiplantibacillus plantarum Lp-115 inhibit Helicobacter pylori colonization and gastric inflammation in a murine model. Front Cell Infect Microbiol. 13:1196084. PMID: 37621875 Why chosen: This is a 2023 mouse study testing NCFM together with Lp-115 against Helicobacter pylori. It is the only source here for the gastric inflammation claim, and the evidence is indirect, since mice are not people. I labeled it an animal model in both sections where it appears. It earns its place by giving a plausible mechanism, and I do not let it carry more weight than that.

[3] Sanchez MC, Herraiz A, Tigre S, et al. (2023). Evidence of the Beneficial Impact of Three Probiotic-Based Food Supplements on the Composition and Metabolic Activity of the Intestinal Microbiota in Healthy Individuals: An Ex Vivo Study. Nutrients. 15(24). PMID: 38140334 Why chosen: This is a 2023 ex vivo study that ran three probiotic supplements through human fecal batch cultures. Supplements containing NCFM raised butyrate production. The setup uses real human gut bacteria, which puts it a step above a bare cell line, though it stays a lab system rather than a person eating a product. I cite it as mechanism support rather than a health outcome.

[4] Lucin GA, Marques CG, Magalhaes ACO, et al. (2026). Effect of continuous energy restriction combined with probiotic supplementation on parameters related to homeostatic and hedonic systems of food intake in adult men living with obesity. Clin Nutr ESPEN. 75:103444. PMID: 42392542 Why chosen: This is a 2026 randomized, parallel, double-blind, placebo-controlled trial in adult men with obesity. I use it for the finding that probiotic supplementation alongside calorie restriction changed the homeostatic and hedonic pathways behind food intake. The design is as tight as nutrition trials get. The population is the limit: men with obesity on a restricted diet, so the result says little about anyone else.

[5] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus… Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 taxonomy paper again, this time for a different point. Most lactobacilli moved to new genera, but acidophilus stayed in Lactobacillus sensu stricto. That contrast is worth flagging for readers who assume every name in the group changed. It carries no clinical data.

[6] Sanders ME, Klaenhammer TR. (2001). “Invited review: the scientific basis of Lactobacillus acidophilus NCFM functionality as a probiotic.” J Dairy Sci. 84(2):319-331. PMID: 11233016 Why chosen: This is a 2001 invited review on the scientific basis for NCFM as a probiotic. It sits in the reference list as general background rather than behind a specific claim in the entry. It is a review, and it predates the 2005 genome paper, so its molecular detail is dated. I kept it because it summarizes the original case for using NCFM as a probiotic.

[1] Chatsirisakul O, Leenabanchong N, Siripaopradit Y, et al. (2025). Strain-Specific Therapeutic Potential of Lactiplantibacillus plantarum: A Systematic Scoping Review. Nutrients. 17(7). PMID: 40218922 Why chosen: This is a 2025 systematic scoping review of strain-specific effects of L. plantarum. I cite it in the Mechanism section for the broad claim that 299v acts on gut barrier function and immune tuning. A scoping review maps a literature rather than pooling effect sizes, so it is weaker than a meta-analysis. I use it to show several groups have reported the same mechanism, which a single study could not establish.

[2] Maslennikov R, Gosteeva E, Ananeva V, et al. (2026). Strain-Specific Systematic Review with Meta-Analysis of Probiotics Efficacy in the Treatment of Irritable Bowel Syndrome. J Clin Med. 15(3):1152. PMID: 41682832 Why chosen: This is the 2026 strain-specific systematic review and meta-analysis, the same one cited for LcS. I use it twice: in the Overview to show that 299v’s research centers on IBS and on exercise-related gut effects, and in Health benefit for the pooled finding that it helps IBS symptoms. Meta-analysis sits at the top of the evidence hierarchy, so this is the load-bearing citation in the entry. The caveat is that it is new, and the result has not had time to be retested.

[3] Hansson E, Skinner B, Falcone T, et al. (2026). Effects of race distance and probiotics intervention on kidney, muscle, and gut injury and inflammation biomarker responses during running. J Int Soc Sports Nutr. 23(1):2651356. PMID: 41981959 Why chosen: This is a 2026 randomized controlled trial in runners, testing how race distance plus a 299v supplement affect injury and inflammation biomarkers. It found shifts in kidney, muscle, and gut injury markers. The entry does not claim this means less injury or faster recovery, because the study measured biomarkers rather than outcomes a runner would feel. It is the most recent trial here and it backs the exercise angle named in the Overview.

[4] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus… Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 taxonomy paper, cited for the rename to Lactiplantibacillus plantarum. Same reason as in the other entries: most studies still carry the old name Lactobacillus plantarum, so a reader needs the link. No clinical data here.

[5] Nordstrom EA, Teixeira C, Montelius C, et al. (2021). “Lactiplantibacillus plantarum 299v (LP299V): three decades of research.” Benef Microbes. 12(4):339-350. PMID: 34365915 Why chosen: This is a 2021 review covering three decades of research on 299v. It carries no specific claim in the entry and functions as background. A 30-year review is a reasonable place to trace the older trials, which are hard to find one at a time. It adds no new data.

[6] Axling U, Onning G, Combs MA, et al. (2020). “The Effect of Lactobacillus plantarum 299v on Iron Status and Physical Performance in Female Iron-Deficient Athletes: A Randomized Controlled Trial.” Nutrients. 12(5):1252. PMID: 32365981 Why chosen: This is a 2020 randomized controlled trial on 299v, iron status, and physical performance in female iron-deficient athletes. The entry attaches no specific claim to it, so it sits as background on the exercise side. It is a real trial in a defined group, which is more than a lot of the exercise literature offers. The population is narrow, so I would not generalize from it.

[1] Kleerebezem M, Boekhorst J, van Kranenburg R, et al. (2003). Complete genome sequence of Lactobacillus plantarum WCFS1. Proc Natl Acad Sci U S A. 100(4):1990-1995. PMID: 12566566 Why chosen: This is the 2003 genome paper for WCFS1, and it carries more of this entry than any other reference. It is the source for the first-sequenced-Lactobacillus claim, the three plasmids, the broad sugar metabolism, and plantaricin. It also sits behind the adhesion and immune claims in Health benefit, which is a lot to ask of a genome paper, and I kept it there because those sentences describe what the strain is equipped to do rather than any measured result in a patient. The paper reports no health outcome.

[2] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus… Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 taxonomy paper again, supporting the rename to Lactiplantibacillus plantarum. I use the same reference in every plantarum entry for consistency. No clinical data.

[3] Leimena MM, Wels M, Bongers RS, et al. (2012). “Comparative analysis of Lactobacillus plantarum WCFS1 transcriptomes by using DNA microarray and next-generation sequencing technologies.” Appl Environ Microbiol. 78(12):4234-4242. PMID: 22492454 Why chosen: This is a 2012 methods study comparing DNA microarray and next-generation sequencing for reading WCFS1 transcriptomes. It is a validation study, so it shows the tools work rather than showing anything about health. The entry attaches no claim to it. I kept it because WCFS1 is mostly a lab model strain, and anyone using it should know how its gene expression gets measured.

[1] Pridmore RD, Berger B, Desiere F, et al. (2004). The genome sequence of the probiotic intestinal bacterium Lactobacillus johnsonii NCC 533. Proc Natl Acad Sci U S A. 101(8):2512-2517. PMID: 14983040 Why chosen: This is the genome paper for NCC 533, published in 2004. It is where the hard biological facts in this entry come from: the GC content of 34.6 percent and the strain’s placement in the acidophilus group. It also identified the adhesion genes, including the EF-Tu surface protein named in the Mechanism section. It carries no clinical data at all. I use it as the identity card for the strain, not as evidence that it does anything for a person.

[2] Granato D, Bergonzelli GE, Pridmore RD, et al. (2004). Cell surface-associated elongation factor Tu mediates the attachment of Lactobacillus johnsonii NCC533 (La1) to human intestinal cells and mucins. Infect Immun. 72(4):2160-2169. PMID: 15039339 Why chosen: This is the paper that found the adhesion mechanism. It showed the EF-Tu protein sits on the outer surface of the cell and sticks to human intestinal cells and to mucins. The work is in vitro, so it shows what the strain can do in a dish. I kept it because adhesion is the mechanism the other claims in this entry sit on top of.

[3] Denou E, Pridmore RD, Berger B, et al. (2008). Identification of genes associated with the long-gut-persistence phenotype of the probiotic Lactobacillus johnsonii strain NCC533 using a combination of genomics and transcriptome analysis. J Bacteriol. 190(9):3161-3168. PMID: 18223069 Why chosen: This paper asks why the strain stays in the gut longer than others. The authors combined genome and transcriptome data and pointed at motility genes and carbohydrate breakdown genes. It supports one sentence in the Mechanism section, so it carries a small load. It is a genomics study with no human outcomes. I kept it because persistence is the original reason anyone picked this strain.

[4] Beau A, Natividad J, Benoit B, et al. (2025). A specifically designed multi-biotic reduces uremic toxin generation and improves kidney function. Gut Microbes. 17(1):2531202. PMID: 40650408 Why chosen: This is the newest paper in the entry, from 2025, and it reported better kidney-function markers in chronic kidney disease models. The strain was one ingredient in a multi-biotic mixture, so the result cannot be credited to it alone. It is also animal work, which is indirect evidence for human health. I included it to show the strain still shows up in current research, and I marked it as the weakest health claim here.

[5] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus… Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: This is the 2020 paper that split the old genus Lactobacillus into 23 new genera. It kept johnsonii inside Lactobacillus sensu stricto instead of moving it out. I cite it in the Biology section for that one naming fact. It contains no strain performance data. Without it, the names in this entry would be out of date.

[1] Rosander A, Connolly E, Roos S. (2008). Removal of antibiotic resistance gene-carrying plasmids from Lactobacillus reuteri ATCC 55730 and characterization of the resulting daughter strain, L. reuteri DSM 17938. Appl Environ Microbiol. 74(19):6032-6040. PMID: 18689509 Why chosen: This is the paper that built the strain. The authors removed the plasmids carrying antibiotic resistance genes from the parent strain ATCC 55730 and produced DSM 17938. That one fact explains why the strain exists and why it gets sold for children. It supports seven sentences across five sections here, from gut colonization in Biology to the Protectis oil drops in Available products. It is the anchor of the entry. PubMed tags it as a comparative study, and some of its claims come from lab work plus a small human trial.

[2] Bianchi M, et al. (2026). Efficacy of Lactobacillus reuteri DSM 17938 in preterm newborns and infants with colic: a systematic review and meta-analysis of randomized controlled trials. Nutrition. 151:113327. PMID: 42485904 Why chosen: This is the strongest evidence in the entry. It is a systematic review and meta-analysis pooling randomized trials, and it found less crying and fussing time in breastfed infants with colic. The certainty rating was moderate, not high, which the entry says out loud. It applies to one narrow group, breastfed infants. I made it the headline health claim on that basis.

[3] Szajewska H, Kołodziej M, Zalewski BM, Dinleyici EC, Łukasik J. (2026). Systematic review: Limosilactobacillus reuteri DSM 17938 for preventing antibiotic-associated diarrhoea in children. J Pediatr Gastroenterol Nutr. 82(3):781-789. PMID: 41486369 Why chosen: This systematic review looked at preventing antibiotic-associated diarrhea in children. I used it for the negative finding, that regimens of 14 days or less did nothing. Including the null result keeps the entry honest about dose. It is a review, so it summarizes other people’s trials and adds no new data of its own.

[4] Rerksuppaphol L, Rerksuppaphol S. (2025). Efficacy of Lactobacillus reuteri DSM 17938 in Thai children with acute gastroenteritis and normal or mild dehydration in an outpatient setting: a randomized controlled trial. J Trop Pediatr. 71(4). PMID: 40618229 Why chosen: This is a single randomized trial and it failed. It found no drop in stool frequency or illness duration against placebo in Thai children with acute gastroenteritis. I put it in because an entry that lists only wins is not useful to a reader. It is one trial in one country, in outpatients with only mild dehydration, so it narrows the claim rather than killing it.

[5] Ermann Lundberg L, et al. (2025). Selection, characterisation and safety of Limosilactobacillus reuteri DSM 32846, an evolved version of DSM 17938. Benef Microbes. 17(4):413-430. PMID: 41067711 Why chosen: This paper describes DSM 32846, a newer version of the strain selected for better survival. I use it for the Mechanism sentence about stress tolerance and for the product note on young child formula with GOS. It is primary lab characterization work with no patient outcomes. The survival and stress claims come from the same group that developed the strain, so I treat them as company-adjacent.

[6] Zheng J, et al. (2020). A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 genus split moved reuteri from Lactobacillus to Limosilactobacillus based on whole-genome phylogeny. I cite it in Overview and Biology for the naming and nothing else. It says nothing about probiotic effect. The entry would use outdated names without it.

[7] Indrio F, et al. (2026). Long-Term Efficacy of Limosilactobacillus reuteri DSM17938 in the Prevention of Functional Abdominal Pain Disorders. Nutrients. 18(4). PMID: 41754204 Why chosen: This is a randomized trial with a long-term follow-up period, and it looked at preventing functional abdominal pain disorders in children. The entry says suggested rather than showed, because prevention from one trial with extended follow-up is weaker than the pooled result in reference 2. I included it as the newest clinical signal for the strain. It is one study, and the entry keeps that visible.

[1] Reid G, et al. (2003). Oral use of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 significantly alters vaginal flora: randomized, placebo-controlled trial in 64 healthy women. FEMS Immunol Med Microbiol. 35(2):131-134. PMID: 12628548 Why chosen: This is the trial that put these two strains on the map. It was randomized and placebo-controlled, with 64 healthy women taking the strains by mouth. It showed the organisms actually change vaginal flora after being swallowed, which is the core mechanism claim in this entry. The sample is small and the paper is from 2003. It also tested RC-14 together with GR-1, so I cannot separate the two. The title uses the older name L. fermentum RC-14, which is why the taxonomy reference at the end of this entry matters.

[2] Hummelen R, Changalucha J, Butamanya NL, Cook A, Habbema JD, Reid G. (2010). Lactobacillus rhamnosus GR-1 and L. reuteri RC-14 to prevent or cure bacterial vaginosis among women with HIV. Int J Gynaecol Obstet. 111(3):245-248. PMID: 20801446 Why chosen: This randomized trial tested the pair in women with HIV, a group with high rates of bacterial vaginosis. It reported a benefit on vaginal pH with an odds ratio of 3.8 and a P value of 0.02. The endpoint is a lab measurement, not how patients felt or how often they got sick. It is one trial in a specific population, and again it used both strains together.

[3] Zhang Y, et al. (2021). Probiotic Lacticaseibacillus rhamnosus GR-1 and Limosilactobacillus reuteri RC-14 as an Adjunctive Treatment for Bacterial Vaginosis Do Not Increase the Cure Rate in a Chinese Cohort: A Prospective, Parallel-Group, Randomized, Controlled Study. Front Cell Infect Microbiol. 11:669901. PMID: 34295831 Why chosen: This trial added the pair to metronidazole in a Chinese cohort and found no extra cure rate for bacterial vaginosis. I kept it because it contradicts the older positive trials, and a reader deserves to see both sides. It is a straightforward randomized trial with a clear negative result. The combination design means it does not tell us much about RC-14 on its own.

[4] Sharpe M, et al. (2021). Effectiveness of oral intake of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 on Group B Streptococcus colonization during pregnancy: a midwifery-led double-blind randomized controlled pilot trial. J Matern Fetal Neonatal Med. 34(11):1814-1821. PMID: 31362572 Why chosen: This is a pilot trial, small by design, run in pregnant women and led by midwives. It found no reduction in Group B Streptococcus colonization. A pilot study cannot prove there is no effect either, so I report it as one more place the evidence stops. I included it because the entry would otherwise suggest the pair works in pregnancy when this trial says it did not.

[5] Reid G. (2008). Probiotic Lactobacilli for urogenital health in women. J Clin Gastroenterol. 42 Suppl 3 Pt 2:S234-S236. PMID: 18685506 Why chosen: This short review by Gregor Reid supplies several facts the primary trials do not. The entry draws on it for the biosurfactant mechanism, the drop in pro-inflammatory signals from epithelial cells, and the isolation site in the human distal urethra. It is a review, so it carries the author’s reading rather than new data. Reid also ran much of the primary work cited here, so this source is not independent of it.

[6] Reid G, Bruce AW. (2006). “Probiotics to prevent urinary tract infections: the rationale and evidence.” World J Urol. 24(1):28-32. PMID: 16389539 Why chosen: This 2006 review lays out the reasoning behind using probiotics against urinary tract infections. I use it for one thing, the note that the combination is marketed internationally under several brand names. It is a review with no new trial data. I kept it so the Available products section points at published literature instead of at product pages.

[7] Zheng J, et al. (2020). A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 genus split moved this organism from Lactobacillus reuteri to Limosilactobacillus reuteri, and the entry follows that naming. It is pure taxonomy with no probiotic data. I cite it because references 1 and 5 in this entry use the old names, and a reader moving between entries needs the translation.

[1] Ozen M, Piloquet H, Schaubeck M. (2023). Limosilactobacillus fermentum CECT5716: Clinical Potential of a Probiotic Strain Isolated from Human Milk. Nutrients. 15(9):2207. PMID: 37432320 Why chosen: This 2023 review is the summary paper for the whole strain. I use it for the origin story in Overview, the European follow-on formula products, and most of the Mechanism section, including the in vitro work against E. coli and on interleukin-6. It is a review, so the primary data sits in other papers. Nothing it supports comes from human trials, and the entry labels those sentences as in vitro or animal.

[2] Piloquet H, et al. (2024). Efficacy and safety of a synbiotic infant formula for the prevention of respiratory and gastrointestinal infections: a randomized controlled trial. Am J Clin Nutr. 119(5):1259-1269. PMID: 38462218 Why chosen: This randomized trial tested a synbiotic infant formula against standard formula for preventing respiratory and gastrointestinal infections. It is the human trial sitting behind the infection claims in this entry. The product was a synbiotic, so the strain was not tested alone and I cannot give CECT5716 the whole result. It also carries the product note about the HiPP and Hero Baby lines.

[3] Blanco-Rojo R, et al. (2022). Beneficial Effects of Limosilactobacillus fermentum CECT 5716 Administration to Infants Delivered by Cesarean Section. Front Pediatr. 10:906924. PMID: 35874592 Why chosen: This study looked at infants born by cesarean section, who start out with a different gut microbiota. It found the strain partly restored that deficit. Partial is the important word, and the outcome measured was microbiota composition rather than illness. PubMed tags it only as a journal article, so the RCT label in the entry text comes from the study itself and is not confirmed in the record.

[4] Pastor-Villaescusa B, Blanco-Rojo R, Olivares M. (2021). Evaluation of the Effect of Limosilactobacillus fermentum CECT5716 on Gastrointestinal Infections in Infants: A Systematic Review and Meta-Analysis. Microorganisms. 9(7). PMID: 34208893 Why chosen: The title says systematic review and meta-analysis, and the entry treats it that way, but PubMed tags it only as a review, which is a gap worth knowing. It concluded the strain reduces gastrointestinal infections in infants, which makes it the second strongest health source here after the individual trials. I also used it for the Overview sentence about reducing infections in formula-fed infants, since it pools that data.

[5] Hurtado Suazo JA, et al. (2025). L. Fermentum CECT5716 and B. Breve CECT7263 on premature infants morbidities: a randomized clinical trial. Pediatr Res. PMID: 41310220 Why chosen: This multicenter randomized trial gave two strains, CECT5716 and B. breve CECT7263, to premature infants and tracked necrotizing enterocolitis and late-onset sepsis. The two-strain design means results cannot be credited to CECT5716 alone. The entry says it assessed those outcomes rather than naming a benefit, because nothing in the source gives an effect size I can quote. It is the most recent health paper in the entry.

[6] Zheng J, et al. (2020). A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 reclassification moved fermentum from Lactobacillus to Limosilactobacillus. It supports two sentences here, both about naming. It is not evidence for any health effect, and I treat it as a citation of convenience rather than a source of findings.

[1] Koga Y, Ohtsu T, Kimura K, Asami Y. (2019). Probiotic L. gasseri strain (LG21) for the upper gastrointestinal tract acting through improvement of indigenous microbiota. BMJ Open Gastroenterol. 6(1):e000314. PMID: 31523442 Why chosen: This 2019 review covers a different gasseri strain, LG21, and it is a review rather than primary data. I use it for species-level facts: the organism lives in the human gut and vagina, and it competes for stomach adhesion sites and shifts the native gastric microbiota. Those claims involve H. pylori and come from in vitro work. I keep it out of the Health benefit section on purpose, because benefits do not transfer between strains of the same species.

[2] Takagi A, et al. (2016). Effects of Lactobacillus gasseri OLL2716 on Helicobacter pylori-Associated Dyspepsia: A Multicenter Randomized Double-Blind Controlled Trial. Gastroenterol Res Pract. 2016:7490452. PMID: 27478434 Why chosen: This multicenter double-blind trial tested OLL2716, another gasseri strain, in people with H. pylori-associated dyspepsia, and the entry says symptoms improved against placebo. It is a sibling strain rather than SBT2055, so it supports the species and not this specific product. PubMed tags it only as a journal article even though the title describes a randomized trial. I use it together with reference 1 to source the upper-GI background.

[3] Ohtsu T, et al. (2017). The Ameliorating Effect of Lactobacillus gasseri OLL2716 on Functional Dyspepsia in Helicobacter pylori-Uninfected Individuals: A Randomized Controlled Study. Digestion. 96(2):92-102. PMID: 28768250 Why chosen: This randomized study also used OLL2716, this time in people without H. pylori, and found effects on delayed gastric emptying. It shares the same weakness as reference 2, since the strain is not SBT2055. I included it because the stomach claims in this entry come from these two papers, and dropping either one would leave the entry with no upper-GI data at all.

[4] Kawano M, et al. (2016). Lactobacillus gasseri SBT2055 inhibits adipose tissue inflammation and intestinal permeability in mice fed a high-fat diet. J Nutr Sci. 5:e23. PMID: 27293560 Why chosen: This is the mouse study behind the metabolic claims, with some rat data as well. It found less adipose tissue inflammation and better glucose tolerance and insulin sensitivity in animals on a high-fat diet. Animal work does not tell us much about people, and the entry labels both of its sentences as animal. I cite it twice, once in Mechanism for the microbiota shift and once in Health benefit.

[5] Kobatake E, et al. (2017). Protective effects and functional mechanisms of Lactobacillus gasseri SBT2055 against oxidative stress. PLoS One. 12(5):e0177106. PMID: 28493927 Why chosen: This one studies SBT2055 itself, not a stand-in, so it is the strain-specific source for the oxidative stress work. It reports that the strain turns on stress-response genes and scavenges reactive oxygen species. Everything it supports is in vitro, meaning cells or test tubes. I also use it for the Overview sentence on the Snow Brand and Megmilk history and for the fermented milk products in Available products.

[6] Zheng J, et al. (2020). A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 reclassification kept gasseri inside the emended Lactobacillus genus instead of moving it out. I cite it in the Overview naming sentence and in Biology. It appears across many entries in this document because the same paper renamed most of the strains used here.

[7] Mehra Y, Viswanathan P. (2021). “High-quality whole-genome sequence analysis of Lactobacillus paragasseri UBLG-36 reveals oxalate-degrading potential of the strain.” PLoS One. 16(11):e0259136. PMID: 34797858 Why chosen: This paper sequenced the genome of UBLG-36, a related strain, and found it can degrade oxalate. I use it only for the naming point that some sources list SBT2055 as Lactobacillus paragasseri, plus one Biology sentence about the gasseri species complex. The strain it studied is not SBT2055, so the oxalate finding does not carry over. Two short naming sentences is the whole load it carries.

[8] Kadooka Y, Sato M, Imaizumi K, et al. (2010). “Regulation of abdominal adiposity by probiotics (Lactobacillus gasseri SBT2055) in adults with obese tendencies in a randomized controlled trial.” Eur J Clin Nutr. 64(6):636-643. PMID: 20216555 Why chosen: This is the main human trial for the strain. It was randomized and multicenter, ran 12 weeks in adults with obese tendencies, and reported a significant reduction in abdominal adiposity with the fermented milk. It is the oldest SBT2055 trial in the entry, from 2010. The entry leans on it more than on any other paper, so it carries the biggest load here.

[9] Kadooka Y, Sato M, Ogawa A, et al. (2013). “Effect of Lactobacillus gasseri SBT2055 in fermented milk on abdominal adiposity in adults in a randomised controlled trial.” Br J Nutr. 110(9):1696-1703. PMID: 23614897 Why chosen: This is the follow-up trial, longer at 24 weeks, and it reached the same result on abdominal adiposity. Two trials agreeing beats one, and the longer duration adds something the 2010 paper could not. The entry still needs the caveat that both came from the same research group, so this is a replication by the same lab rather than independent confirmation.

[10] Ogawa A, Kadooka Y, Kato K, et al. (2014). “Lactobacillus gasseri SBT2055 reduces postprandial and fasting serum non-esterified fatty acid levels in Japanese hypertriacylglycerolemic subjects.” Lipids Health Dis. 13:36. PMID: 24548293 Why chosen: This trial shifted the outcome from body fat to blood markers and found lower non-esterified fatty acids both after meals and during fasting in people with high triglycerides. PubMed tags it as a clinical trial rather than a randomized one, so the design is less clear than for references 8 and 9. The endpoint is a surrogate marker, not a disease outcome, which I do not want a reader to miss.

[11] Ogawa A, Kobayashi T, Sakai F, et al. (2015). “Lactobacillus gasseri SBT2055 suppresses fatty acid release through enlargement of fat emulsion size in vitro and promotes fecal fat excretion in healthy Japanese subjects.” Lipids Health Dis. 14:20. PMID: 25884980 Why chosen: This study bridges the mouse work and the human trials, since it measured fat emulsion size in vitro and fecal fat excretion in people. The subjects were healthy, so it says nothing about treating a disease. It is a randomized trial and a useful piece of the fat story, but the effect it shows is a mechanism step rather than a health benefit anyone would feel.

[1] Foster LM, Tompkins TA, Dahl WJ. (2011). A comprehensive post-market review of studies on a probiotic product containing Lactobacillus helveticus R0052 and Lactobacillus rhamnosus R0011. Benef Microbes. 2(4):319-334. PMID: 22146691 Why chosen: This is the backbone reference for the entry. It is a 2011 review, so it reports no new data of its own. I use it for three things: the fact that R0052 is sold paired with R0011, the tolerability record, and the product formats. Its main weakness is the pairing. Almost every study inside it tests a two-strain product, so I cannot pull out what R0052 does alone.

[2] Evans M, Salewski RP, Christman MC, Girard SA, Tompkins TA. (2016). Effectiveness of Lactobacillus helveticus and Lactobacillus rhamnosus for the management of antibiotic-associated diarrhoea in healthy adults: a randomised, double-blind, placebo-controlled trial. Br J Nutr. 116(1):94-103. PMID: 27169634 Why chosen: This is the strongest human evidence I found for this strain pair. It is a 2016 randomized, double-blind, placebo-controlled trial in healthy adults, and it found a shorter duration of antibiotic-associated diarrhoea. Two limits matter. The trial tests R0052 together with L. rhamnosus, and the outcome is diarrhoea, which has nothing to do with rhinitis. I included it because it is real human endpoint data, which is rare for this strain.

[3] Wiącek J, et al. (2025). Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 Supplementation: An Exploratory, Randomized, Placebo-Controlled Trial of Endocannabinoid and Inflammatory Responses in Female Dancers. Microorganisms. 13(6). PMID: 40572172 Why chosen: This is the most recent trial on the list, published in 2025. It measured endocannabinoid and inflammatory markers, which is closer to an immune readout than the diarrhoea work. The problems are clear from the title itself. It is exploratory, the population is female dancers only, and it tests R0052 with B. longum R0175. I treat it as a signal, not proof.

[4] Johnson-Henry KC, Hagen KE, Gordonpour M, Tompkins TA, Sherman PM. (2007). Surface-layer protein extracts from Lactobacillus helveticus inhibit enterohaemorrhagic Escherichia coli O157:H7 adhesion to epithelial cells. Cell Microbiol. 9(2):356-367. PMID: 16925785 Why chosen: I use this one purely for the Mechanism section. It is a 2007 cell culture study showing that surface-layer proteins from the strain block a pathogen from sticking to epithelial cells. That is a direct, visible mechanism. It is also the weakest kind of evidence here, because cells in a dish are not a human gut.

[5] Wang Q, et al. (2019). Lactobacillus helveticus R0052 alleviates liver injury by modulating gut microbiome and metabolome in D-galactosamine-treated rats. Appl Microbiol Biotechnol. 103(23-24):9673-9686. PMID: 31713675 Why chosen: This is a 2019 rat study, so the evidence is indirect. Rats given D-galactosamine are not people with rhinitis, and the target organ is the liver. I kept it because it is one of the few studies that looks at R0052 on its own and identifies anti-inflammatory and barrier-protective pathways. The mechanism may transfer even though the disease model does not.

[6] Zheng J, et al. (2020). A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: This is the naming paper. The 2020 reclassification split the old genus Lactobacillus into 23 new genera, and this is the source that settles where helveticus landed, which is inside the emended genus. It carries no health data at all. I cite it in Overview and Biology so the names on this page match current usage.

[1] Di Cerbo A, Palmieri B. (2013). Lactobacillus Paracasei subsp. Paracasei F19; a farmacogenomic and clinical update. Nutr Hosp. 28(6):1842-1850. PMID: 24506359 Why chosen: This 2013 review holds up more of the entry than any other source. It is cited in five sections, covering infant formula use, competitive exclusion of pathogens in vitro, metabolic and inflammatory markers at school age, Scandinavian product history, and where the species lives. That breadth is also its weakness. It is a review, so every claim in it is secondhand, and I had to check the primary trials behind the health claims.

[2] Compare D, et al. (2015). Lactobacillus paracasei F19 versus placebo for the prevention of proton pump inhibitor-induced bowel symptoms: a randomized clinical trial. Dig Liver Dis. 47(4):273-279. PMID: 25660822 Why chosen: This is a 2015 multicenter randomized trial against placebo, and it reports that F19 prevented bowel symptoms caused by proton pump inhibitors in adults. It is one of the few clean adult human endpoints for this strain. The catch is that the outcome is gastrointestinal and drug related. It tells me the strain survives and acts in the human gut, which is a fair starting point, but it says nothing about allergy.

[3] Szajewska H, et al. (2017). Effects of infant formula supplemented with prebiotics compared with synbiotics on growth up to the age of 12 mo: a randomized controlled trial. Pediatr Res. 81(5):752-758. PMID: 28060791 Why chosen: This 2017 multicenter randomized trial followed infants to 12 months and found growth comparable to breastfed infants. I cite it for the Health benefit line about breastfed comparability and for the product link to Probi AB. It is a real trial, but I am careful with it. The comparison is prebiotic formula against synbiotic formula, and the outcome is growth. It is safety and tolerance evidence, not a treatment result.

[4] West CE, Hammarström ML, Hernell O. (2013). Probiotics in primary prevention of allergic disease--follow-up at 8-9 years of age. Allergy. 68(8):1015-1020. PMID: 23895631 Why chosen: This is a negative result and I kept it for that reason. It is the long-term follow-up of an infant randomized trial, and at 8 to 9 years of age it found no effect on allergy or eczema prevention. Any honest page about probiotics and allergy has to show the trials that failed. The follow-up is also observational at that point, since families were only re-checked years later.

[5] Schott AS, Behr J, Quinn J, Vogel RF. (2016). MALDI-TOF Mass Spectrometry Enables a Comprehensive and Fast Analysis of Dynamics and Qualities of Stress Responses of Lactobacillus paracasei subsp. paracasei F19. PLoS One. 11(10):e0165504. PMID: 27783652 Why chosen: This 2016 study is laboratory work, not clinical work. It profiled how F19 changes its proteins under gastrointestinal stress conditions. I use it two ways: it supports the Mechanism section, and it backs the Biology claim that the strain is identifiable at strain level by mass spectrometry and enzyme profiling. That matters because probiotic effects are strain specific and you need to know the identity was confirmed.

[6] Zheng J, et al. (2020). A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. Int J Syst Evol Microbiol. 70(4):2782-2858. PMID: 32293557 Why chosen: This is where the name change comes from. The 2020 whole-genome phylogeny moved paracasei out of Lactobacillus and into Lacticaseibacillus, which is why the page title differs from the older product labels. It contributes no clinical evidence. It earns its place by making the naming correct.

[1] Claesson MJ, et al. (2006). “Multireplicon genome architecture of Lactobacillus salivarius.” Proc Natl Acad Sci U S A. 103(17):6718–23. PMID: 16617113 Why chosen: This is the genome paper, published in PNAS in 2006. It gives the exact architecture I quote in the entry: a 2.13 Mb chromosome, a 242 kb megaplasmid called pMP118, and two smaller plasmids at 20 kb and 44 kb. It also identified bile salt hydrolase and cell-surface proteins. It is primary data with hard numbers, and it carries no clinical claim, which is fine for the Biology section.

[2] Flynn S, van Sinderen D, Thornton GM, Holo H, Nes IF, Collins JK. (2002). “Characterization of the genetic locus responsible for the production of ABP-118, a novel bacteriocin produced by the probiotic bacterium Lactobacillus salivarius subsp. salivarius UCC118.” Microbiology (Reading). 148(Pt 4):973–984. PMID: 11932444 Why chosen: This 2002 paper is the source for most of the Mechanism section. It mapped the genetic locus for ABP-118, including the immunity gene, the quorum sensing peptide AbpIP, and the secretion machinery. It also says the strain came from the human ileal-caecal region. It was the first bacteriocin from a known human probiotic characterized at the genetic level. That is a milestone, but it is molecular genetics, not evidence that anyone gets better.

[3] O’Shea EF, et al. (2012). “Subspecies diversity in bacteriocin production by intestinal Lactobacillus salivarius strains.” Gut Microbes. 3(5):468–73. PMID: 22892690 Why chosen: This is a 2012 review, and it is cited only once, for a short fragment in the Biology section. I kept it because it frames how variable bacteriocin production is across salivarius strains, which explains why one strain’s results cannot be copied onto another. It adds no new measurements of UCC118 itself, so I lean on it lightly.

[4] O’Callaghan J, Buttó LF, MacSharry J, Nally K, O’Toole PW. (2012). “Influence of adhesion and bacteriocin production by Lactobacillus salivarius on the intestinal epithelial cell transcriptional response.” Appl Environ Microbiol. 78(15):5196–203. PMID: 22610429 Why chosen: I should flag this one. No sentence in the current strain entry actually cites it, so its contribution is background only. The paper itself is a 2012 cell culture study asking how adhesion and bacteriocin production change the transcriptional response of intestinal epithelial cells. That fits the Mechanism story, but since no claim in the text rests on it, it is a candidate to cut or to tie to a specific sentence later.

[5] Axelrod CL, et al. (2019). “UCC118 supplementation reduces exercise-induced gastrointestinal permeability and remodels the gut microbiome in healthy humans.” Physiol Rep. 7(22):e14276. PMID: 31758610 Why chosen: This is a 2019 randomized controlled trial in healthy humans, which makes it the strongest clinical source here. It found reduced exercise-induced gut permeability and shifts in 99 bacterial types across six major groups. I use it for both the Mechanism and Health benefit sections. The population is healthy adults and the trigger is exercise, so it does not translate to disease treatment. It does show the strain acts in a living human gut.

[6] Iyer N, et al. (2022). “Lactobacillus salivarius UCC118™ Dampens Inflammation and Promotes Microbiota Recovery to Provide Therapeutic Benefit in a DSS-Induced Colitis Model.” Microorganisms. 10(7). PMID: 35889102 Why chosen: This is a 2022 mouse study using the DSS colitis model, so the evidence is indirect. It reported less inflammation, faster recovery of the gut microbial community, and higher tissue IL-10 with M2 macrophage markers. Animal models of colitis are a long way from any human use, and I say so. I kept it because the immune markers are specific and measurable.

[7] Zheng J, et al. (2020). “A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae.” Int J Syst Evol Microbiol. 70(4):2782–2858. PMID: 32293557 Why chosen: This is the 2020 taxonomy source behind the Ligilactobacillus name. It is cited in Overview and Biology only. No health claim hangs on it. It is here so the genus name on the page matches the current classification rather than the older Lactobacillus label used in most product literature.

[1] Chaillou S, et al. (2005). “The complete genome sequence of the meat-borne lactic acid bacterium Lactobacillus sakei 23K.” Nat Biotechnol. 23(12):1527–33. PMID: 16273110 Why chosen: This is the genome sequence paper from 2005, and it is the foundation of the entry. It explains why the strain is described as meat-borne and it names the specific adaptation genes I list: nucleoside breakdown, the arginine deiminase pathway, and cold-shock proteins that allow growth at refrigeration temperatures. It is primary sequence data with no human component, so it supports Biology and Mechanism only.

[2] Dudez AM, et al. (2002). “Physical and genetic map of the Lactobacillus sakei 23K chromosome.” Microbiology (Reading). 148(Pt 2):421–431. PMID: 11832506 Why chosen: This 2002 paper came before the full genome and built the physical and genetic map of the chromosome. It located the metabolic and bacteriocin genes and gave later work a scaffold. I kept it because the entry mentions that scaffold role. It is largely superseded by the 2005 sequence, and I would not cite it for anything a reader could act on.

[3] Eisenbach L, Geissler AJ, Ehrmann MA, Vogel RF. (2019). “Comparative genomics of Lactobacillus sakei supports the development of starter strain combinations.” Microbiol Res. 221:1–9. PMID: 30825936 Why chosen: This 2019 comparative genomics paper found strain-level diversity in bacteriocin clusters and sugar metabolism, and it argues that this diversity can guide starter culture design. It is cited in Mechanism and Biology. It is food science, not medicine. It tells you how the strain behaves in fermented meat, and I do not stretch it into a health claim.

[4] Yu L, et al. (2024). “Latilactobacillus sakei: a candidate probiotic with a key role in food fermentations and health promotion.” Crit Rev Food Sci Nutr. 64(4):978–995. PMID: 35997270 Why chosen: This is a 2024 review, so it summarizes rather than reports. I use it for two claims: that the strain is a model organism for bacteriocin production, cold tolerance, and food preservation, and that it is being studied as a candidate probiotic for respiratory and gut uses. The word candidate is the honest part. A review calling something a candidate means the human data are thin.

[5] Abreu NA, et al. (2012). “Sinus microbiome diversity depletion and Corynebacterium tuberculostearicum enrichment mediates rhinosinusitis.” Sci Transl Med. 4(151):151ra124. PMID: 22972842 Why chosen: This is the paper that made me include this strain at all. It compared the sinus microbiomes of chronic rhinosinusitis patients against healthy people, found diversity loss and enrichment of Corynebacterium tuberculostearicum, and then showed protection against that organism in a mouse sinus infection model. It is the only citation here that touches my own condition. I am careful about it, because the human part is correlational and the protection was shown in mice.

[6] Chiaramonte F, Blugeon S, Chaillou S, Langella P, Zagorec M. (2009). “Behavior of the meat-borne bacterium Lactobacillus sakei during its transit through the gastrointestinal tracts of axenic and conventional mice.” Appl Environ Microbiol. 75(13):4498–505. PMID: 19447958 Why chosen: This 2009 mouse study tracked what happens to the strain during gut transit. It showed the bacterium uses host sialic acids through the NanI and NanR system, responds to the surrounding microbial community, and can reach and persist in the gut briefly. All of that is indirect. Mice are not people, and short persistence is a modest result. It answers a basic question, which is whether a meat bacterium can survive a gut at all.

[7] Zheng J, et al. (2020). “A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae.” Int J Syst Evol Microbiol. 70(4):2782–2858. PMID: 32293557 Why chosen: This is the source for the 2020 move of sakei into the new genus Latilactobacillus. It is cited only in Overview and Biology. It provides no functional or clinical information. It is here so the species name on the page is current.

[1] Bloom SM, et al. (2026). “Vaginal microbiota impacts of a Lactobacillus crispatus live biotherapeutic and predictors of colonization in randomized controlled trial.” Cell Host Microbe. 34(4):734–750.e10. PMID: 41903526 Why chosen: This is a 2026 phase II randomized controlled trial, and it is the newest source in the entry. I use it in the Mechanism section because it separates the effect of the product from the effect of actual CTV-05 colonization, and it shows the biotherapeutic group keeping other bacteria suppressed. It also supports the Biology claim that crispatus strains help rebuild the microbiome after treatment. Phase II means it is still mid-stage, and the endpoint is microbial rather than clinical.

[2] Haahr T, et al. (2025). “Efficacy of clindamycin and LACTIN-V for in vitro fertilization patients with vaginal dysbiosis: a randomised double-blind, placebo-controlled multicentre trial.” Nat Commun. 16(1):5166. PMID: 40467561 Why chosen: This is the best-designed trial on the list. It is a 2025 randomized, double-blind, placebo-controlled multicentre trial, and it found that clindamycin plus LACTIN-V improved vaginal imbalance in IVF patients. Multicentre blinding with a placebo arm is about as strong as probiotic evidence gets. One caveat: the intervention combines an antibiotic with the biotherapeutic, so the design cannot fully separate what LACTIN-V contributed on its own.

[3] Hemmerling A, et al. (2025). “Effect of the vaginal live biotherapeutic LACTIN-V (Lactobacillus crispatus CTV-05) on vaginal microbiota and genital tract inflammation among women at high risk of HIV acquisition in South Africa: a phase 2, randomised, placebo-controlled trial.” Lancet Microbe. 6(6):101037. PMID: 40194532 Why chosen: This 2025 phase 2 randomized placebo-controlled trial in South African women at high risk of HIV infection found that LACTIN-V changed the vaginal microbiota and lowered genital tract inflammation. It is cited in both Mechanism and Health benefit for that reason. The population is specific and the outcome measured is inflammation, not infection rates, so I do not push it further than the data go.

[4] Hemmerling A, Wierzbicki MR, Armstrong E, Cohen CR. (2024). “Response to Antibiotic Treatment of Bacterial Vaginosis Predicts the Effectiveness of LACTIN-V (Lactobacillus crispatus CTV-05) in the Prevention of Recurrent Disease.” Sex Transm Dis. 51(6):437–440. PMID: 38733973 Why chosen: I cite this 2024 analysis for one uncomfortable finding: LACTIN-V did not work in women who were not cured by the antibiotic first. That conditional result matters more to me than another positive one, because it defines who the product actually helps. It comes from subgroup analysis within a trial, so it is weaker than a prespecified primary outcome.

[5] Armstrong E, et al. (2024). “Vaginal Lactobacillus crispatus persistence following application of a live biotherapeutic product: colonization phenotypes and genital immune impact.” Microbiome. 12(1):110. PMID: 38907268 Why chosen: This 2024 study is observational rather than randomized. It sorted women by whether CTV-05 persisted after they stopped the product, and found that non-colonizers had higher pre-treatment microbial diversity and signs of epithelial disruption, while sustained colonization came with distinct immune profiles. It explains the mechanism behind why the same product works for some people and not others. Without a control arm, it shows association rather than cause.

[6] Bayar E, et al. (2023). “Safety, tolerability, and acceptability of Lactobacillus crispatus CTV-05 (LACTIN-V) in pregnant women at high-risk of preterm birth.” Benef Microbes. 14(1):45–56. PMID: 36815494 Why chosen: This 2023 study is observational, nested inside a trial, and it answers only a safety question: the product was safe, tolerable, and acceptable in pregnant women at high risk of preterm birth. I included it because safety in pregnancy is a separate question from efficacy and readers will ask. It does not test whether the product prevents anything.

[7] Lagenaur LA, et al. (2021). “Connecting the Dots: Translating the Vaginal Microbiome Into a Drug.” J Infect Dis. 223(12 Suppl 2):S296–S306. PMID: 33330916 Why chosen: This 2021 paper covers how the vaginal microbiome gets turned into a drug, and I lean on it for the background claims: that losing crispatus is a hallmark of bacterial vaginosis, that these bacteria keep pH low and block pathogens from returning, and that CTV-05 was first isolated from the vaginal microbiome of a healthy woman. Two honest notes. The entry also cites it for the genus staying in Lactobacillus after the 2020 reclassification, which is secondhand, since this is not the taxonomy paper itself. And the paper is written by developers of the product, so I read its framing with that in mind.

[1] Satomi S, Waki N, Arakawa C, Fujisawa K, Suzuki S, Suganuma H. (2021). “Effects of Heat-Killed Levilactobacillus brevis KB290 in Combination with β-Carotene on Influenza Virus Infection in Healthy Adults: A Randomized Controlled Trial.” Nutrients. 13(9). PMID: 34578917 Why chosen: This is the strongest item here, a 2021 randomized controlled trial with a real clinical endpoint. Healthy adults taking heat-killed KB290 got influenza at 1.9% against 3.9% on placebo. Two things hold it back. The bacteria were given together with beta-carotene, so the trial cannot separate KB290 from the combination, and the absolute gap is about two percentage points.

[2] Fuke N, Aizawa K, Suganuma H, Takagi T, Naito Y. (2017). “Effect of combined consumption of Lactobacillus brevis KB290 and β-carotene on minor diarrhoea-predominant irritable bowel syndrome-like symptoms in healthy subjects: a randomised, double-blind, placebo-controlled, parallel-group trial.” Int J Food Sci Nutr. 68(8):973–986. PMID: 28391736 Why chosen: Same group and the same design problem as [1]. This 2017 randomized, double-blind, placebo-controlled trial again tested KB290 with beta-carotene rather than KB290 alone. I use it for the immune readout, since serum IL-10 rose in the treatment arm. The population was healthy subjects with mild diarrhea-predominant IBS-like symptoms, not people carrying an IBS diagnosis, so the finding sits at the soft end.

[3] Fuke N, et al. (2018). “Lactobacillus brevis KB290 With Vitamin A Ameliorates Murine Intestinal Inflammation Associated With the Increase of CD11c+ Macrophage/CD103− Dendritic Cell Ratio.” Inflamm Bowel Dis. 24(2):317–331. PMID: 29361084 Why chosen: This is a mouse study, so the evidence is indirect for humans. PubMed does not tag the publication type beyond Journal Article, but the title names it murine. Its value is mechanism: KB290 with vitamin A calmed intestinal inflammation alongside a higher CD11c+ macrophage to CD103− dendritic cell ratio. I cite it in Mechanism for that reason and nowhere as proof of a human benefit. Vitamin A was co-administered here too, which is the same confound running through this strain’s literature.

[4] Fukao M, et al. (2019). “Plasmid-encoded glycosyltransferase operon is responsible for exopolysaccharide production, cell aggregation, and bile resistance in a probiotic strain, Lactobacillus brevis KB290.” J Biosci Bioeng. 128(4):391–397. PMID: 31126721 Why chosen: Pure bench work with no clinical claim attached, and the most cited source in this entry. It locates the exopolysaccharide machinery on the 42.4-kb plasmid pKB290-1 in a three-gene unit, gtf27, gtf28, orf29, with orf29 coding for an ABC transporter. The plasmid-cure experiment is the strong part. Take the plasmid out and the cells lose EPS production, clumping, and bile resistance together, which is cause and effect rather than correlation. It also reports the sugar composition, glucose and N-acetylglucosamine, and how sharply output falls when the cells grow on arabinose or xylose.

[5] Fukao M, et al. (2019). “Relation between cell-bound exopolysaccharide production via plasmid-encoded genes and rugose colony morphology in the probiotic Lactobacillus brevis KB290.” Anim Sci J. 90(12):1575–1580. PMID: 31593351 Why chosen: A companion to [4] from the same group in the same year. It ties the wrinkled colony look of KB290 to cell-bound EPS made by those same plasmid genes, and explains smooth variants as reduced EPS expression. The claim is narrow. Its usefulness is that a visible trait tracks a molecular one, so anyone reading a plate can tell which cells are making EPS.

[6] Watanabe J, et al. (2021). “Heat-killed Lactobacillus brevis KB290 attenuates visceral fat accumulation induced by high-fat diet in mice.” J Appl Microbiol. 131(4):1998–2009. PMID: 33742756 Why chosen: This one does two jobs. In Overview it is the source for where the strain came from, suguki, a traditional Japanese fermented pickle. In Mechanism and Health benefit it supplies the mouse data, where heat-killed KB290 cut visceral fat accumulation and improved glucose, insulin, and HOMA-IR in animals on a high-fat diet. The metabolic signal is real but it comes from mice. I read it as indirect.

[7] Zheng J, et al. (2020). “A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae.” Int J Syst Evol Microbiol. 70(4):2782–2858. PMID: 32293557 Why chosen: No health content at all. This is the 2020 taxonomic paper that broke up the old genus Lactobacillus, creating 23 novel genera, and moved brevis into Levilactobacillus. Every entry involving this species needs it, because every trial above was published under the name Lactobacillus brevis. Without this citation a reader searching one name and finding the other assumes two different organisms.

[1] van de Guchte M, et al. (2006). “The complete genome sequence of Lactobacillus bulgaricus reveals extensive and ongoing reductive evolution.” Proc Natl Acad Sci U S A. 103(24):9274–9. PMID: 16754859 Why chosen: This genome paper is the backbone of most of the biology here. Sequencing showed ongoing reductive evolution: many pseudogenes, high rRNA and tRNA gene density, and a rare 47.5-kbp inverted repeat at the replication termination region. It reads as specialization to a stable, protein and lactose rich milk environment, which explains why the organism keeps shedding genes it no longer needs. Published in 2006 and genomic rather than clinical, so for mechanism it is the primary source, and for health outcomes it says nothing.

[2] Kok CR, Hutkins R. (2018). “Yogurt and other fermented foods as sources of health-promoting bacteria.” Nutr Rev. 76(Suppl 1):4–15. PMID: 30452699 Why chosen: A 2018 review, which I lean on for the broad claims in Health benefit, mainly better lactose digestion and immune system tuning from fermented foods. Those effects are well rehearsed for yogurt cultures, and I wanted a peer-reviewed review rather than a health blog to say so. It contributes no new data of its own. It also speaks about yogurt bacteria generally, so nothing here is specific to ATCC 11842.

[3] Ashraf R, Shah NP. (2011). “Selective and differential enumerations of Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium spp. in yoghurt - a review.” Int J Food Microbiol. 149(3):194-208. PMID: 21807435 Why chosen: Honest caveat up front. This 2011 review is about counting methods, specifically how to selectively enumerate each yogurt species separately, so it is not a health study. It earns its slot because reliable counting is what lets anyone check that a live culture survives into the product at a claimed dose. I cite it behind the probiotic claim of fermented dairy rather than behind any mechanism.

[4] Girardeau A, et al. (2022). “Insights into lactic acid bacteria cryoresistance using FTIR microspectroscopy.” Anal Bioanal Chem. 414(3):1425–1443. PMID: 34967915 Why chosen: Source for the freeze-sensitivity note in Biology, plus the section’s discussion of how the strain handles cold. Using FTIR microspectroscopy, it linked cryoresistance differences across lactic acid bacteria to fatty acid makeup, membrane fluidity, and lipid phase behavior during cooling, and it found this strain more freeze-sensitive than its relatives. It also found wider cell-to-cell variation here. That matters for anyone asking whether a frozen or freeze-dried product actually delivers live cells.

[5] Li C, et al. (2016). “Growth and acid production of Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 in the fermentation of algal carcass.” J Dairy Sci. 99(6):4243–4250. PMID: 26995135 Why chosen: One citing sentence, one claim. This 2016 fermentation study put the strain on algal carcass and showed it can grow and produce acid there, which is the basis for saying it can use alternative materials. The scope is small and it carries no health or mechanism depth. I kept it because metabolic flexibility outside milk is genuinely interesting for a dairy-adapted organism.

[6] Zheng J, et al. (2020). “A taxonomic note on the genus Lactobacillus: Description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae.” Int J Syst Evol Microbiol. 70(4):2782–2858. PMID: 32293557 Why chosen: The same 2020 reclassification paper I use throughout this document, cited here for the opposite outcome to strain 16. This subspecies stayed inside the narrowed Lactobacillus genus, while brevis was moved out. I include it so readers who see Lactobacillus bulgaricus in older work and Lactobacillus delbrueckii subsp. bulgaricus in newer work know the names line up.

[1] Bolotin A, et al. (2004). “Complete sequence and comparative genome analysis of the dairy bacterium Streptococcus thermophilus.” Nat Biotechnol. 22(12):1554–8. PMID: 15543133 Why chosen: The genome paper for this species, published in Nature Biotechnology in 2004, and the reason Overview can call it one half of the classic yogurt starter pair with L. bulgaricus. In Biology it carries two specific findings: limited ability to make its own nutrients, and a single urease operon. It also set up the comparative framework that later dairy adaptation work relies on. It is old and purely genomic, which is fine, since I use it for biology and context rather than for any clinical claim.

[2] Zhang Y, et al. (2024). “Live and Heat-Inactivated Streptococcus thermophilus MN-ZLW-002 Mediate the Gut-Brain Axis, Alleviating Cognitive Dysfunction in APP/PS1 Mice.” Nutrients. 16(6). PMID: 38542758 Why chosen: This 2024 study carries most of the mechanism content in this entry, including five separate citing sentences. In APP/PS1 mice it compared live against heat-killed MN-ZLW-002 and found they act differently. Heat-killed cells raised colonic propionic acid and antioxidant capacity in the hippocampus, and high doses reduced astrogliosis. Spatial memory improved most of the outcomes measured. It is a mouse model of Alzheimer’s pathology, so nobody should read a dementia claim off it for healthy people.

[3] Luo Y, et al. (2022). “Influence of high-fat diet on host animal health via bile acid metabolism and benefits of oral-fed Streptococcus thermophilus MN-ZLW-002.” Exp Anim. 71(4):468–480. PMID: 35793979 Why chosen: Another mouse study, this one on high-fat diet through the lens of bile acid metabolism. MN-ZLW-002 improved blood glucose, liver cholesterol buildup, and serum IL-10, and it counteracted the shift toward an obese-type bile acid pattern. I labeled the evidence level as animal model in Health benefit so nobody mistakes it for human data. The bile acid angle is the specific reason to keep it, since few other entries in this document touch that pathway.

[4] Kang X, et al. (2021). “Streptococcus thermophilus MN-ZLW-002 Can Inhibit Pre-adipocyte Differentiation through Macrophage Activation.” Biol Pharm Bull. 44(3):316–324. PMID: 33390424 Why chosen: Cell work rather than animals or people. It shows MN-ZLW-002 suppresses pre-adipocyte differentiation indirectly by activating macrophages, with phosphorylation of p38, p44/42 MAPK, and NF-kB downstream. The detail that earns it a place is the RNase result. RNase treatment removed the effect, which points to bacterial RNA as the trigger. In vitro findings support how questions, and they say little about what happens in a person.

[5] Albuquerque MAC, Yamacita DS, Bedani R, LeBlanc JG, Saad SMI. (2019). “Influence of passion fruit by-product and fructooligosaccharides on the viability of Streptococcus thermophilus TH-4 and Lactobacillus rhamnosus LGG in folate bio-enriched fermented soy products and their effect on probiotic survival and folate bio-accessibility under in vitro simulated gastrointestinal conditions.” Int J Food Microbiol. 292:126–136. PMID: 30597427 Why chosen: The TH-4 half of this entry, all about folate. Fermenting soy with passion fruit by-product and fructooligosaccharides raised folate content, and folate stayed bio-accessible under simulated gastrointestinal conditions. The same paper supplies the counterweight I mention in Mechanism: TH-4 viability fell during storage. The gut work is an in vitro simulation rather than a human feeding study, so I treat the bio-accessibility finding as weaker than it sounds.

[6] van den Akker CHP, et al. (2020). “Probiotics and Preterm Infants: A Position Paper by the European Society for Paediatric Gastroenterology Hepatology and Nutrition Committee on Nutrition and the European Society for Paediatric Gastroenterology Hepatology and Nutrition Working Group for Probiotics and Prebiotics.” J Pediatr Gastroenterol Nutr. 70(5):664–680. PMID: 32332478 Why chosen: This is expert guidance rather than data. ESPGHAN published it as a position paper on probiotics and preterm infants, and I cite it because multi-strain products containing S. thermophilus show up in that setting and I wanted a guideline-level source to say so. Both citing sentences are fragments, which is a weakness in how the entry uses it. Nothing in the captured text attributes a specific outcome to this strain, so it establishes context rather than effect.

[1] Whorwell PJ, Altringer L, Morel J, Bond Y, Charbonneau D, O’Mahony L, et al. (2006). Efficacy of an encapsulated probiotic Bifidobacterium infantis 35624 in women with irritable bowel syndrome. Am J Gastroenterol. 101(7):1581-90. PMID: 16863564 Why chosen: The flagship trial, a multicenter RCT in 362 women with irritable bowel syndrome from 2006. Abdominal pain, discomfort, bloating, and difficulty passing stool all fell significantly against placebo at the 1x10^8 CFU dose. Two limits I want visible. The benefit attaches to one specific dose rather than the highest one, which is the kind of pattern that invites doubt, and the trial enrolled women only, so it says nothing about men. It is also old enough that IBS diagnostic criteria have moved since.

[2] Yuan F, Ni H, Asche CV, Kim M, Walayat S, Ren J. (2017). Efficacy of Bifidobacterium infantis 35624 in patients with irritable bowel syndrome: a meta-analysis. Curr Med Res Opin. 33(7):1191-1197. PMID: 28166427 Why chosen: This is the highest rung available for this strain, a meta-analysis pooled specifically on 35624 rather than on probiotics in general. It puts overall IBS symptom improvement at RR 1.58 with a 95% CI of 1.21 to 2.06, comfortably clear of 1.0. The constraint is the pool itself. A strain-specific meta-analysis draws on few trials, and one large trial inside it can drive most of the pooled estimate.

[3] Ringel-Kulka T, McRorie J, Ringel Y. (2017). Multi-Center, Double-Blind, Randomized, Placebo-Controlled, Parallel-Group Study to Evaluate the Benefit of the Probiotic Bifidobacterium infantis 35624 in Non-Patients With Symptoms of Abdominal Discomfort and Bloating. Am J Gastroenterol. 112(1):145-151. PMID: 27845337 Why chosen: A 2017 multicenter RCT in 302 volunteers that significantly reduced bloating, though P=0.04 sits close to the conventional threshold. The participants were non-patients with abdominal discomfort rather than people meeting IBS criteria, so this is a milder population than [1]. That difference is useful rather than disqualifying, since it suggests the bloating effect extends past diagnosed patients. It also supplies the Overview fact that the strain was developed at University College Cork.

[4] Charbonneau D, Gibb RD, Quigley EM. (2013). Fecal excretion of Bifidobacterium infantis 35624 and changes in fecal microbiota after eight weeks of oral supplementation with encapsulated probiotic. Gut Microbes. 4(3):201-11. PMID: 23549409 Why chosen: This 2013 randomized study does two things for the entry. It establishes that the strain shows up in stool during supplementation and transiently colonizes without permanently restructuring the native microbiota, which is why the mechanism is framed as passage plus temporary presence. It also documents the commercial form, sold as Align in capsules by Procter & Gamble. A reader should notice that the product and the research come from the same commercial thread.

[5] Konieczna P, Akdis CA, Quigley EM, Shanahan F, O’Mahony L. (2012). Portrait of an immunoregulatory Bifidobacterium. Gut Microbes. 3(3):261-6. PMID: 22572827 Why chosen: I will be straight about this one. No citing sentence in the captured text carries its number, so it is background reading rather than a pinned claim. From the title it is a review describing how this bifidobacterium behaves as an immunoregulatory organism, which is the territory the Mechanism section keeps circling. Reviews assemble existing work and generate nothing new. If I dropped it, the entry would lose framing rather than facts.

[6] Groeger D, O’Mahony L, Murphy EF, Bourke JF, Dinan TG, Kiely B, et al. (2013). Bifidobacterium infantis 35624 modulates host inflammatory processes beyond the gut. Gut Microbes. 4(4):325-39. PMID: 23842110 Why chosen: This is what lets Mechanism reach past the intestine. In psoriasis patients, oral administration changed plasma cytokine profiles, so the strain touches systemic inflammation rather than only the gut lining. PubMed tags it as a randomized controlled trial, which is why it outranks the pure reviews here. I do not have a sample size to quote for it, and the endpoint is a cytokine panel rather than a clinical outcome, so I would not oversell it.

[7] Maslennikov R, Gosteeva E, Ananeva V, Korshunova L, Kravtsowa A, Poluektova E, et al. (2026). Strain-Specific Systematic Review with Meta-Analysis of Probiotics Efficacy in the Treatment of Irritable Bowel Syndrome. J Clin Med. 15(3):1152. PMID: 41682832 Why chosen: Recency is the contribution. This 2026 strain-specific systematic review with meta-analysis places 35624 among the probiotics with evidence for IBS symptom improvement, which means the claim survives a second pass by authors working from newer literature than [2]. I cite the conclusion rather than a figure from it, since the captured sentence carries no effect size. Anyone wanting the pooled number should open the paper.

[8] O’Hara AM, O’Regan P, Fanning A, O’Mahony C, Macsharry J, Lyons A, et al. (2006). Functional modulation of human intestinal epithelial cell responses by Bifidobacterium infantis and Lactobacillus salivarius. Immunology. 118(2):202-15. PMID: 16771855 Why chosen: Like [5], no sentence in this entry currently carries its reference number. It is 2006 laboratory work on how Bifidobacterium infantis and Lactobacillus salivarius modulate human intestinal epithelial cell responses, so the evidence sits in cells rather than people. I kept it because it explains the mucosal step underneath the clinical results above. The title names the species without the 35624 designator, so it is less strain-resolved than the trials.

[9] Roman P, Carrillo-Trabalon F, Sanchez-Labraca N, Canadas F, Estevez AF, Cardona D. (2018). Are probiotic treatments useful on fibromyalgia syndrome or chronic fatigue syndrome patients? A systematic review. Benef Microbes. 9(4):603-611. PMID: 29695180 Why chosen: I cite this one to restrain a claim rather than to build one. It is a 2018 systematic review asking whether probiotics help fibromyalgia or chronic fatigue syndrome, and the entry records its answer as preliminary with low-quality evidence. Keeping it is deliberate: people self-treat those conditions with this strain, and an honest entry should say the evidence is thin there. A review of weak primary studies produces a weak conclusion, which is the point.

[10] Mattarelli P, Bonaparte C, Pot B, Biavati B. (2008). Proposal to reclassify the three biotypes of Bifidobacterium longum as three subspecies: Bifidobacterium longum subsp. longum subsp. nov., Bifidobacterium longum subsp. infantis comb. nov. and Bifidobacterium longum subsp. suis comb. nov. Int J Syst Evol Microbiol. 58(Pt 4):767-72. PMID: 18398167 Why chosen: The nomenclature anchor for this entry. In 2008 it proposed reclassifying the three biotypes of Bifidobacterium longum as subspecies, which turned Bifidobacterium infantis into Bifidobacterium longum subsp. infantis. That is why the 2006 trials above write B. infantis 35624 while later sources write the longer name. Zero health content, but without it the two search terms never meet.

[1] Jungersen M, Wind A, Johansen E, Christensen JE, Stuer-Lauridsen B, Eskesen D. (2014). The Science behind the Probiotic Strain Bifidobacterium animalis subsp. lactis BB-12. Microorganisms. 2(2):92-110. PMID: 27682233 Why chosen: A 2014 review doing most of the work in this entry, cited across five sections. It supplies the scale claim of over 300 publications and more than 130 clinical studies, the use-since-1985 history, the product list in Available products, and the safety line about no systemic infections being attributed to the strain. It also carries the mechanism: toll-like receptor interaction, acetate through the bifid shunt, and a transient rise in fecal bifidobacteria without permanent restructuring of the microbiota. One review propping up that much is its own weakness. It synthesizes trials without being one, and a 2014 cutoff cannot see anything published since.

[2] Van Rossum T, Haiss A, Knoll RL, MariBen J, Podlesny D, Pagel J, et al. (2024). Bifidobacterium and Lactobacillus Probiotics and Gut Dysbiosis in Preterm Infants: The PRIMAL Randomized Clinical Trial. JAMA Pediatr. 178(10):985-995. PMID: 39102225 Why chosen: High rung design. This 2024 Phase III multicenter randomized trial in JAMA Pediatrics measured gut dysbiosis in preterm infants given Bifidobacterium and Lactobacillus probiotics. The catch is written into my own citing sentence: BB-12 appears in a multi-strain context, so no outcome separates it from the companion strains. I cite what the trial measured rather than what it found, and I keep it because a JAMA-level trial frames the whole infant section better than another review would.

[3] van den Akker CHP, van Goudoever JB, Shamir R, Domellof M, Embleton ND, Hojsak I, et al. (2020). Probiotics and Preterm Infants: A Position Paper by the European Society for Paediatric Gastroenterology Hepatology and Nutrition Committee on Nutrition and the European Society for Paediatric Gastroenterology Hepatology and Nutrition Working Group for Probiotics and Prebiotics. J Pediatr Gastroenterol Nutr. 70(5):664-680. PMID: 32332478 Why chosen: The same 2020 ESPGHAN position paper that appears in strain 18. Here it certifies that BB-12 is among the strains named in that document, which is a credibility marker rather than an effect size. Position papers summarize what a committee already accepts, so this proves no benefit on its own. It tells a reader that the strain is visible to clinical guideline writers, which is a different thing.

[4] Masco L, Ventura M, Zink R, Huys G, Swings J. (2004). Polyphasic taxonomic analysis of Bifidobacterium animalis and Bifidobacterium lactis reveals relatedness at the subspecies level: reclassification of Bifidobacterium animalis as Bifidobacterium animalis subsp. animalis subsp. nov. and Bifidobacterium lactis as Bifidobacterium animalis subsp. lactis subsp. nov. Int J Syst Evol Microbiol. 54(Pt 4):1137-1143. PMID: 15280282 Why chosen: The taxonomy paper, cited once in Biology. Its 2004 polyphasic analysis folded Bifidobacterium lactis into Bifidobacterium animalis at subspecies level, which is why the full name reads Bifidobacterium animalis subsp. lactis today while older trials write B. lactis. No health content whatsoever. Like the other systematics references in this document, it exists so old names and new names resolve to the same organism.

[5] Salvatore S, Carlino M, Sestito S, Concolino D, Agosti M, Pensabene L. (2024). Nutraceuticals and Pain Disorders of the Gut-Brain Interaction in Infants and Children: A Narrative Review and Practical Insights. Nutrients. 16(3):349. PMID: 38337634 Why chosen: A 2024 narrative review on nutraceuticals for gut-brain interaction pain disorders in infants and children. I take one narrow piece from it, the judgment that RCT evidence for constipation in adults and elderly is moderate in strength. Narrative reviews sit lowest among review types, because authors choose their sources instead of screening them systematically. I lean on it for calibration language rather than for numbers, and it is recent enough to be useful.

[1] Cheng J, Laitila A, Ouwehand AC. (2021). Bifidobacterium animalis subsp. lactis HN019 Effects on Gut Health: A Review. Front Nutr. 8:790561. PMID: 34970580 Why chosen: This is a 2021 review, not primary data. I use it for the background facts: the strain came from a New Zealand yogurt source, and it sells mostly in Asia-Pacific and North America. It also frames the health benefit list (constipation, gut transit, microbiota changes). A review is the weakest kind of source here, so nothing in the entry rests on it alone.

[2] Waller PA, Gopal PK, Leyer GJ, Ouwehand AC, Reifer C, Stewart ME, et al. (2011). Dose-response effect of Bifidobacterium lactis HN019 on whole gut transit time and functional gastrointestinal symptoms in adults. Scand J Gastroenterol. 46(9):1057-64. PMID: 21663486 Why chosen: This is a randomized controlled trial, and it tested three doses rather than one. The top dose of 1.7x10^10 CFU/day cut whole gut transit time from 49 to 36 hours (P=0.01). That dose-response shape is the reason I trust it more than a single-arm study. It is still one 2011 trial in adults with GI symptoms, not a replication.

[3] Gill HS, Rutherfurd KJ, Cross ML, Gopal PK. (2001). Enhancement of immunity in the elderly by dietary supplementation with the probiotic Bifidobacterium lactis HN019. Am J Clin Nutr. 74(6):833-9. PMID: 11722966 Why chosen: A 2001 randomized controlled trial in elderly people. Three weeks of HN019 raised the phagocytic capacity of PMN cells (P<0.05) and raised NK cell tumoricidal activity. It is one of the earlier human trials on this strain. The endpoints are immune lab markers, not infections prevented, so the result is suggestive rather than clinical.

[4] Miller LE, Lehtoranta L, Lehtinen MJ. (2017). The Effect of Bifidobacterium animalis ssp. lactis HN019 on Cellular Immune Function in Healthy Elderly Subjects: Systematic Review and Meta-Analysis. Nutrients. 9(3):191. PMID: 28245559 Why chosen: This is the strongest item on the immune claim. It is a systematic review with a meta-analysis, and the pooled effect sizes came out significant for both phagocytic activity and NK cell activity. Pooling beats the single 2001 trial above. The limit is that it pools immune markers in healthy elderly people, and it pools a small number of trials.

[5] D’Ambrosio S, Dabous A, Sadiq S, Casillo A, Schiraldi C, Cassese E, et al. (2024). Bifidobacterium animalis subsp. lactis HN019 live probiotics and postbiotics: production strategies and bioactivity evaluation for potential therapeutic properties. Front Bioeng Biotechnol. 12:1379574. PMID: 39055336 Why chosen: I cite this once, in Mechanism, for acetate production. Acetate is the main energy source for colon cells. PubMed tags it only as a Journal Article, with no trial or review label, so it reads as lab and bioengineering work. That is fine for a mechanism claim and weak for anything clinical.

[6] Cheng J, Gao C, Ala-Jaakkola R, Forssten SD, Saarinen M, Hibberd A, et al. (2024). Eight-Week Supplementation With Bifidobacterium lactis HN019 and Functional Constipation: A Randomized Clinical Trial. JAMA Netw Open. 7(10):e2436888. PMID: 39356506 Why chosen: This is a 2024 randomized clinical trial in JAMA Network Open on the constipation question. It is recent and it sits in a high-profile journal. The entry does not pull a specific number from it in the captured text, so I keep it as supporting weight behind the constipation claim rather than as the quoted result.

[7] Ala-Jaakkola R, Forssten SD, Cheng J, Griffon F, Metreau I, Sturm Y, et al. (2025). Effect of an 8-Week Bifidobacterium lactis HN019 Supplementation on Functional Constipation: A Multi-Center, Triple-Blind, Randomized, Placebo-Controlled Trial. Mol Nutr Food Res. 69(17):e70081. PMID: 40320938 Why chosen: This is the newest trial on the same endpoint, run in 2025 across multiple centers with triple blinding. The design is tighter than most probiotic work. No specific result from it is quoted in the captured text. I include it so the constipation section reflects the current evidence, not just the 2011 dose-response study.

[8] Masco L, Ventura M, Zink R, Huys G, Swings J. (2004). Polyphasic taxonomic analysis of Bifidobacterium animalis and Bifidobacterium lactis reveals relatedness at the subspecies level: reclassification of Bifidobacterium animalis as Bifidobacterium animalis subsp. animalis subsp. nov. and Bifidobacterium lactis as Bifidobacterium animalis subsp. lactis subsp. nov. Int J Syst Evol Microbiol. 54(Pt 4):1137-1143. PMID: 15280282 Why chosen: This is a taxonomy paper, cited only in Biology for the 2004 reclassification that moved B. lactis under B. animalis as a subspecies. It carries no health evidence at all. I include it because the name used on product labels changed, and readers need to know why old papers say B. lactis.

[1] Wong CB, Iwabuchi N, Xiao JZ. (2019). Exploring the Science behind Bifidobacterium breve M-16V in Infant Health. Nutrients. 11(8):1724. PMID: 31349739 Why chosen: A 2019 review that covers the whole strain. I lean on it for the origin (isolated from the feces of a healthy infant), the safety position in preterm and term infants, the Th1/Th2 balance point in Mechanism, and the map of what has actually been trialed. It is a review, so it describes trials rather than being one. Every hard claim gets a primary source elsewhere in the entry.

[2] Wang Y, Wopereis H, Kakourou A, Liu M, Wu J, Li Z, et al. (2025). Restoration of gut microbiota with a specific synbiotic-containing infant formula in healthy Chinese infants born by cesarean section. Eur J Clin Nutr. 79(6):567-575. PMID: 39915586 Why chosen: A 2025 randomized controlled trial in cesarean-born Chinese infants. The synbiotic formula containing M-16V restored a Bifidobacterium-dominant microbiota by 12 weeks. Two caveats. The outcome is microbiota composition, which is a surrogate, and the formula also carried prebiotics, so the effect cannot be pinned on the strain alone.

[3] Saez-Fuertes L, Kapravelou G, Grases-Pinto B, Massot-Cladera M, Bernabeu M, Knipping K, et al. (2024). Impact of maternal Bifidobacterium breve M-16V and scGOS/lcFOS supplementation during pregnancy and lactation on the maternal immune system and milk composition. Front Immunol. 15:1418594. PMID: 38975337 Why chosen: This is the weakest item in the entry. PubMed tags it only as a Journal Article, not as a clinical trial, so it most likely reports preclinical work in pregnancy and lactation. No citing sentence from the entry was captured for it. I keep it because maternal supplementation is a real research direction for this strain, and I would rather show a thin source than hide it.

[4] Chew C, Matsuyama M, Davies PSW, Hill RJ, Morrison M, Martin R, et al. (2024). A young child formula supplemented with a synbiotic mixture of scGOS/lcFOS and Bifidobacterium breve M-16V improves the gut microbiota and iron status in healthy toddlers. Front Pediatr. 12:1193027. PMID: 39469104 Why chosen: A 2024 study in healthy toddlers where M-16V plus scGOS/lcFOS in young child formula improved gut microbiota and iron status. The iron finding is unusual and worth showing, since most probiotic endpoints are GI. Two limits: PubMed does not tag it as an RCT even though the entry reads it as one, and the synbiotic mix means the strain is not isolated.

[5] Athalye-Jape G, Esvaran M, Patole S, Nathan EA, Doherty DA, Sim E, et al. (2025). Effects of a live versus heat-inactivated probiotic Bifidobacterium spp in preterm infants: a randomised clinical trial. Arch Dis Child Fetal Neonatal Ed. 110(2):177-184. PMID: 39153842 Why chosen: A 2025 randomized trial in preterm infants that compared live Bifidobacterium against heat-inactivated M-16V and tracked colonization patterns. The live versus killed comparison is the useful part, because it asks whether the bacteria need to be alive. The endpoint is colonization, not a clinical outcome like sepsis or NEC.

[6] Miraglia Del Giudice M, Indolfi C, Capasso M, Maiello N, Decimo F, Ciprandi G. (2017). Bifidobacterium mixture (B longum BB536, B infantis M-63, B breve M-16V) treatment in children with seasonal allergic rhinitis and intermittent asthma. Ital J Pediatr. 43(1):25. PMID: 28270216 Why chosen: A 2017 randomized controlled trial in children with seasonal allergic rhinitis and intermittent asthma, using a three-strain mixture that includes M-16V. This is the one in the entry that maps onto my own chronic rhinitis. The honest flaw is that it is multi-strain, so I cannot say M-16V alone did the work.

[1] Takeda T, Asaoka D, Nojiri S, Yanagisawa N, Nishizaki Y, Osada T, et al. (2023). Usefulness of Bifidobacterium longum BB536 in Elderly Individuals With Chronic Constipation: A Randomized Controlled Trial. Am J Gastroenterol. 118(3):561-568. PMID: 36216361 Why chosen: A 2023 randomized controlled trial in elderly people with chronic constipation, published in a top GI journal. It is the main efficacy source here. The captured result is the bowel frequency comparison, where placebo moved only from 3.3 to 3.6 per week (P<0.05) while the BB536 arm did better. I also take the 1969 Morinaga isolation history and the product availability facts from it. It is still one trial in one population.

[2] Sen A, Kimura M, Ejima R, Arai S, Mitsuyama E, Kaneko H, et al. (2025). Probiotic viability in the gastrointestinal tract in a randomised placebo controlled trial: combining molecular biology and novel cultivation techniques. Benef Microbes. 16(3):271-280. PMID: 39814039 Why chosen: A 2025 randomized placebo-controlled trial that combined molecular methods with new cultivation techniques. I use it in Mechanism for the simple point that viable cells show up in feces, meaning the strain survives the gut. Survival is not a health benefit, and the study title does not name BB536, so the entry leans on it for the survival claim only.

[3] Li Y, Arai S, Kato K, Iwabuchi S, Iwabuchi N, Muto N, et al. (2023). The Potential Immunomodulatory Effect of Bifidobacterium longum subsp. longum BB536 on Healthy Adults through Plasmacytoid Dendritic Cell Activation in the Peripheral Blood. Nutrients. 16(1):42. PMID: 38201872 Why chosen: A randomized controlled trial in healthy adults. BB536 activated plasmacytoid dendritic cells in peripheral blood and raised IFN-alpha production capacity against placebo. That gives the Mechanism section a real human target rather than a guess, and it links to type-1 interferon and innate antiviral responses. The endpoint is a blood marker, so it does not show fewer infections.

[4] Sato S, Arai S, Kato K, Yoshida K, Iwabuchi N, Sagami T, et al. (2024). Effects of Bifidobacterium longum BB536 and Bifidobacterium breve MCC1274 on Body Composition in Normal and Overweight Adults in Randomized Placebo-Controlled Study. Nutrients. 16(6):815. PMID: 38542727 Why chosen: A 2024 randomized placebo-controlled study on body composition in normal and overweight adults. The captured line is only a P<0.05 fragment, so I treat it as weak support. It also tested BB536 alongside B. breve MCC1274, which muddies attribution. I include it to show the strain has been pushed past gut endpoints.

[5] Miraglia Del Giudice M, Indolfi C, Capasso M, Maiello N, Decimo F, Ciprandi G. (2017). Bifidobacterium mixture (B longum BB536, B infantis M-63, B breve M-16V) treatment in children with seasonal allergic rhinitis and intermittent asthma. Ital J Pediatr. 43(1):25. PMID: 28270216 Why chosen: A 2017 randomized controlled trial reporting a significant drop in allergic rhinitis symptom scores (P<0.05) in children. This is the closest thing in the entry to my own condition, which is why I hunted it down. It is a three-strain mixture with BB536, M-63 and M-16V, so the result belongs to the mixture and not to BB536 by itself.

[6] Inoue T, Kobayashi Y, Mori N, Sakagawa M, Xiao JZ, Moritani T, et al. (2018). Effect of combined bifidobacteria supplementation and resistance training on cognitive function, body composition and bowel habits of healthy elderly subjects. Benef Microbes. 9(6):843-853. PMID: 30198326 Why chosen: A 2018 randomized controlled trial in healthy elderly people. Combined bifidobacteria with resistance training improved cognitive function scores. The design is the problem: exercise and probiotic were given together, so the cognitive gain cannot be credited to BB536 alone. I keep it because the combination reflects how the product is actually used.

[7] Mattarelli P, Bonaparte C, Pot B, Biavati B. (2008). Proposal to reclassify the three biotypes of Bifidobacterium longum as three subspecies: Bifidobacterium longum subsp. longum subsp. nov., Bifidobacterium longum subsp. infantis comb. nov. and Bifidobacterium longum subsp. suis comb. nov. Int J Syst Evol Microbiol. 58(Pt 4):767-72. PMID: 18398167 Why chosen: A 2008 taxonomy proposal, cited only in Biology for the reclassification of B. longum biotypes into subspecies. No health claim comes from it. It explains why BB536 now carries the subsp. longum label, and it helps readers follow older papers that just say B. longum.

[1] Smith AR, Macfarlane GT, Reynolds N, O’May GA, Bahrami B, Macfarlane S. (2012). Effect of a synbiotic on microbial community structure in a continuous culture model of the gastric microbiota in enteral nutrition patients. FEMS Microbiol Ecol. 80(1):135-45. PMID: 22176141 Why chosen: This is a lab model, not people. It ran a synbiotic through a continuous culture model of the gastric microbiota built from enteral nutrition patients. No citing sentence from the entry was captured for it. I keep it because this strain has thin human data, and readers deserve to see that some of the support is a bench model.

[2] Bartosch S, Woodmansey EJ, Paterson JC, McMurdo ME, Macfarlane GT. (2005). Microbiological effects of consuming a synbiotic containing Bifidobacterium bifidum, Bifidobacterium lactis, and oligofructose in elderly persons, determined by real-time polymerase chain reaction and counting of viable bacteria. Clin Infect Dis. 40(1):28-37. PMID: 15614689 Why chosen: A 2005 randomized controlled trial in elderly people. Fecal bifidobacterial counts rose from 7.9 to 8.7 log10 CFU/g. It is the only human trial here that reports a number for this strain, which is why it carries both the Mechanism and Health benefit lines. The sample was 18 people, it mixed two Bifidobacterium strains with oligofructose, and the endpoint was bacterial counts rather than how anyone felt.

[3] Jacobs SE, Tobin JM, Opie GF, Donath S, Tabrizi SN, Pirotta M, et al. (2013). Probiotic effects on late-onset sepsis in very preterm infants: a randomized controlled trial. Pediatrics. 132(6):1055-62. PMID: 24249817 Why chosen: A 2013 multicenter randomized controlled trial in very preterm infants, the ProPrems trial, which used a product containing BB-02. I cite it for a negative result: it did not significantly reduce necrotizing enterocolitis or all-cause mortality. I keep negative findings in, since a strain page that only lists wins is advertising. It is also multi-strain, so it does not isolate BB-02.

[4] Plummer EL, Bulach DM, Murray GL, Jacobs SE, Tabrizi SN, Garland SM; ProPrems Study Group. (2018). Gut microbiota of preterm infants supplemented with probiotics: sub-study of the ProPrems trial. BMC Microbiol. 18(1):184. PMID: 30424728 Why chosen: A 2018 sub-study of ProPrems that sequenced the gut microbiota of supplemented preterm infants. It supports the Mechanism line that colonization tracked with microbiota change, including the week 3 contrast against 63% of controls. It is a sub-study of a trial with a null primary result, and the finding is correlational.

[5] van den Akker CHP, van Goudoever JB, Shamir R, Domellof M, Embleton ND, Hojsak I, et al. (2020). Probiotics and Preterm Infants: A Position Paper by the European Society for Paediatric Gastroenterology Hepatology and Nutrition Committee on Nutrition and the European Society for Paediatric Gastroenterology Hepatology and Nutrition Working Group for Probiotics and Prebiotics. J Pediatr Gastroenterol Nutr. 70(5):664-680. PMID: 32332478 Why chosen: A 2020 ESPGHAN position paper, tagged as a consensus statement. I use it for the caution that strain-specific data are needed. It contains no new data of its own, and expert opinion ranks below trials. I put it here because the BB-02 evidence base is small, and a guideline body saying so is more useful to a reader than my own hedging.

[1] Bolotin A, Wincker P, Mauger S, et al. (2001). The complete genome sequence of the lactic acid bacterium Lactococcus lactis ssp. lactis IL1403. Genome Research. 11(5):731-753. PMID: 11337471 Why chosen: A genome paper from 2001 that sequenced IL1403 at 2.365 Mb, the first lactic acid bacterium genome published. I use it in Overview for that milestone and in Biology for the point that this species passes through the mammalian gut rather than colonizing it. It offers no health evidence, and being from 2001 it predates most probiotic trial work.

[2] Wegmann U, O’Connell-Motherway M, Zomer A, et al. (2007). Complete genome sequence of the prototype lactic acid bacterium Lactococcus lactis subsp. cremoris MG1363. Journal of Bacteriology. 189(8):3256-3270. PMID: 17307855 Why chosen: The companion genome paper, published in 2007, covering MG1363 at 2.53 Mb. This entry covers two subspecies, so each one needs its own sequence source. Same limit as the IL1403 paper: it is genome data, and genome data say what a bug could do, not what it does in a person.

[3] Le Bourgeois P, Lautier M, Van den Berghe L, et al. (1995). Physical and genetic maps of the chromosome of the Lactococcus lactis subsp. lactis strain IL1403 and Lactococcus lactis subsp. cremoris strain MG1363. Developments in Biological Standardization. 85:597-603. PMID: 8586238 Why chosen: This is the shakiest citation in the entry. It is a 1995 comparative study tagged also as a review, mapping the chromosomes of both IL1403 and MG1363. The entry cites it in Available products for who sells these strains commercially, which the paper probably does not say. I would rather flag the weak fit than quietly drop it.

[4] Huyghebaert N, Vermeire A, Neirynck S, et al. (2005). Development of an enteric-coated formulation containing freeze-dried, viable recombinant Lactococcus lactis for the ileal mucosal delivery of human interleukin-10. European Journal of Pharmaceutics and Biopharmaceutics. 60(3):349-359. PMID: 15927456 Why chosen: A 2005 formulation study that built an enteric-coated pill with freeze-dried recombinant L. lactis delivering human IL-10 to the ileum. It backs the Mechanism line that local IL-10 can tune the immune system without systemic exposure. It is pharmaceutical development work with no patients, and the entry says plainly that clinical translation stays limited.

[5] Vandenbroucke K, Hans W, Van Huysse J, et al. (2004). Active delivery of trefoil factors by genetically modified Lactococcus lactis prevents and heals acute colitis in mice. Gastroenterology. 127(2):502-513. PMID: 15300583 Why chosen: A 2004 mouse study in Gastroenterology where engineered L. lactis delivered trefoil factors and both prevented and healed acute colitis. It is the proof-of-concept paper for recombinant live biotherapeutics. The evidence is indirect: mice, a genetically modified organism, and an induced colitis model, none of which transfers cleanly to a store-bought probiotic.

[6] Wang X, Kang W, Li J, et al. (2025). Nisin: harnessing nature’s preservative for the future of food safety and beyond. Critical Reviews in Food Science and Nutrition. 65(34):9045-9070. PMID: 40531107 Why chosen: A 2025 systematic review on nisin, the Class I bacteriocin made by L. lactis fermentation and used as preservative E234. It carries four lines across Overview, Mechanism, Health benefit and Available products: the lipid II binding and pore formation, and approval in over 50 countries. A review, and it concerns a food preservative rather than a clinical outcome, so I keep it inside the food-safety frame.

[7] Koebmann BJ, Andersen HW, Solem C, et al. (2002). Experimental determination of control of glycolysis in Lactococcus lactis. Antonie Van Leeuwenhoek. 82(1-4):237-248. PMID: 12369190 Why chosen: A 2002 paper, tagged as both a review and primary work, measuring flux control in glycolysis. It gives the Mechanism line that phosphofructokinase and pyruvate kinase hold the highest flux control coefficients, and the Biology line that hexose fermentation yields only L-lactate. This is basic metabolic physiology from over twenty years ago, and it says nothing about health effects.

[1] Gang H, Wei J, McFarland LV, et al. (2025). Impact of Heyndrickxia (Bacillus) coagulans GBI-30, 6086 (BC30) probiotic on gastrointestinal function in healthy adults: a randomised controlled trial. Beneficial Microbes. 17(1):29-46. PMID: 40707016 Why chosen: This is the anchor paper for the strain. It is a 2025 randomised controlled trial in healthy adults, so it sits at the top of the evidence hierarchy available here. I use it for the hard clinical outcomes: better fecal consistency and less constipation, both at P < 0.001 against placebo. It also supports the microbiome modulation claim and the taxonomic point that clinical work still says Bacillus. It is cited in five of six sections because it is the only recent human trial on this strain that reports symptoms, mechanism, and supplier details together.

[2] Anaya-Loyola MA, Enciso-Moreno JA, López-Ramos JE, et al. (2019). Bacillus coagulans GBI-30, 6068 decreases upper respiratory and gastrointestinal tract symptoms in healthy Mexican scholar-aged children by modulating immune-related proteins. Food Research International. 125:108567. PMID: 31554075 Why chosen: A randomised controlled trial in school-aged children, used here for the single claim that the strain modulates immune-related proteins. I kept it because it is one of the few human trials touching respiratory symptoms, which matters for a reader with rhinitis. The weakness is obvious: the population is healthy children, not adults with rhinitis, and the strain number printed in the title is 6068 rather than 6086. I treat it as supportive, not decisive.

[3] Gepner Y, Hoffman JR, Shemesh E, et al. (2017). Combined effect of Bacillus coagulans GBI-30, 6086 and HMB supplementation on muscle integrity and cytokine response during intense military training. Journal of Applied Physiology. 123(1):11-18. PMID: 28408697 Why chosen: A randomised controlled trial, cited only for cytokine modulation. It is a confounded design: the probiotic was given together with HMB, so you cannot separate the two. I included it because it is still human data on immune markers in a real stress setting, and I flagged the combination so readers do not read it as a clean probiotic effect.

[4] Nyangale EP, Farmer S, Cash HA, et al. (2015). Bacillus coagulans GBI-30, 6086 modulates Faecalibacterium prausnitzii in older men and women. Journal of Nutrition. 145(7):1446-1452. PMID: 25948780 Why chosen: A randomised controlled trial in older adults showing the strain shifts Faecalibacterium prausnitzii, a butyrate producer linked to anti-inflammatory effects. This is a mechanistic endpoint rather than a symptom endpoint, so it supports the mechanism story. The population is older men and women, which limits how far the result travels to younger readers.

[5] Teichenné J, Catalán Ü, Mariné-Casadó R, et al. (2023). Bacillus coagulans GBI-30, 6086 (BC30) improves lactose digestion in rats exposed to a high-lactose meal. European Journal of Nutrition. 62(6):2649-2659. PMID: 37249602 Why chosen: This is a rat study, and I labelled it animal everywhere it appears. It is the only source I have for the lactose hydrolysis mechanism and for the breath hydrogen drop after a lactose challenge. The evidence is indirect: rats are not people. I kept it because the mechanism is otherwise unclaimed, and because the outcome measure (breath hydrogen) is a real physiological readout rather than a marker panel.

[6] Jäger R, Purpura M, Farmer S, et al. (2018). Probiotic Bacillus coagulans GBI-30, 6086 improves protein absorption and utilization. Probiotics and Antimicrobial Proteins. 10(4):611-615. PMID: 29196920 Why chosen: A review, not new data. I lean on it heavily for biology and manufacturing facts: cell size (0.5-1.0 × 2.0-5.0 µm), growth optimum of 35-50°C, spore resistance to heat, drying, and acid, and no gas from glucose. It also backs the baked goods and shelf-stable formulation claim. The muscle recovery line I marked as review-level. This paper is cited eight times because it is the best single descriptive source on the organism, but nothing here is primary evidence.

[7] Gupta RS, Patel S, Saini N, Chen S. (2020). Robust demarcation of 17 distinct Bacillus species clades, proposed as novel Bacillaceae genera, by phylogenomics and comparative genomic analyses: description of Robertmurraya kyonggiensis sp. nov. and proposal for an emended genus Bacillus limiting it only to the members of the Subtilis and Cereus clades of species. International Journal of Systematic and Evolutionary Microbiology. 70(11):5753-5798. PMID: 33112222 Why chosen: This is the taxonomy paper. Whole-genome phylogenetic analysis moved the organism out of Bacillus and into Heyndrickxia. It carries no clinical data at all. I cite it once, in Biology, purely so the name change is not unexplained. Note the citation string is truncated in my source data; I copied it as given.

[1] Mazhar S, Khokhlova E, Colom J, et al. (2023). In vitro and in silico assessment of probiotic and functional properties of Bacillus subtilis DE111. Frontiers in Microbiology. 13:1101144. PMID: 36713219 Why chosen: A lab and computational characterisation study, cited eleven times, mostly for biology and basic properties. It gives me antimicrobial activity, bile tolerance, spore germination, digestive enzyme production (protease, amylase, cellulase), colony appearance, and fermentation products. It also names BIO-CAT as the supplier. None of this is clinical. I use it as the descriptive backbone of the entry and nothing more.

[2] Colom J, Freitas D, Simon A, et al. (2021). Presence and germination of the probiotic Bacillus subtilis DE111 in the human small intestinal tract: a randomized, crossover, double-blind, and placebo-controlled study. Frontiers in Microbiology. 12:715863. PMID: 34408741 Why chosen: This is the strongest mechanistic paper here. It is a randomised crossover trial that recovered vegetative cells from duodenal aspirates, which is direct proof the spores survive the stomach and germinate in the small intestine. That claim is central to the whole entry. It is tagged only as a Journal Article in PubMed despite the trial design in the title, and the sample was small, but the sampling method is unusually direct.

[3] Freedman KE, Hill JL, Wei Y, et al. (2021). Examining the gastrointestinal and immunomodulatory effects of the novel probiotic Bacillus subtilis DE111. International Journal of Molecular Sciences. 22(5):2453. PMID: 33671071 Why chosen: A randomised controlled trial, cited for one thing: anti-inflammatory cytokines went up. That is the human immunomodulation signal that matches the in vitro work. It is a narrow claim from one trial, so I did not stretch it into a clinical benefit.

[4] Trotter RE, Vazquez AR, Grubb DS, et al. (2020). Bacillus subtilis DE111 intake may improve blood lipids and endothelial function in healthy adults. Beneficial Microbes. 11(7):621-630. PMID: 33161737 Why chosen: A randomised controlled trial in healthy adults, cited for improved endothelial function and for the proposed bile acid and short-chain fatty acid mechanism. The title itself says “may,” which is a fair signal that the effects were modest. I kept it because cardiovascular endpoints are a concrete, measurable claim rather than vague wellness language.

[5] Paytuví-Gallart A, Sanseverino W, Winger AM. (2020). Daily intake of probiotic strain Bacillus subtilis DE111 supports a healthy microbiome in children attending day-care. Beneficial Microbes. 11(7):611-620. PMID: 33161736 Why chosen: Cited for one claim: fewer potentially pathogenic bacteria in children in day care. PubMed does not tag it as a randomised controlled trial, so I marked it observational or intervention in the text to be safe. Day-care children are a plausible real-world setting, but the design is weaker than the trials above and the outcome is a microbiome compositional shift, not a health outcome.

[6] Risk BD, Graham EL, Zhang M, et al. (2024). Bacillus subtilis DE111 partially reverses endothelial dysfunction in western-diet fed mice. Beneficial Microbes. 16(3):311-327. PMID: 39631408 Why chosen: A mouse study, labelled animal in both places it appears. It supports the vascular mechanism: less oxidative stress and better nitric oxide availability. The word “partially” in the title is important, and I kept it. This paper explains how the human lipid and endothelial findings might work; it does not confirm that they do.

[7] Townsend JR, Vantrease WC, Jones MD, et al. (2020). “Plasma Amino Acid Response to Whey Protein Ingestion Following 28 Days of Probiotic (Bacillus subtilis DE111) Supplementation in Active Men and Women.” J Funct Morphol Kinesiol. 5(4):90. PMID: 33462163 Why chosen: A negative result, and I included it on purpose. In 15 active men and women, 28 days of DE111 did not change the plasma amino acid response to whey protein. That is a small sample and PubMed does not tag it as a trial. I cite it as a counterweight to the protein absorption marketing around spore-forming probiotics.

[1] McFarland LV, Li T. (2025). Efficacy and safety of Saccharomyces boulardii CNCM I-745 for the treatment of pediatric acute diarrhea in China: a systematic review and meta-analysis. Frontiers in Cellular and Infection Microbiology. 15:1587792. PMID: 40535538 Why chosen: A 2025 systematic review with meta-analysis, the highest evidence tier in this entry. It establishes that the strain cut stool frequency and diarrhea duration against placebo or smectite, and it covers safety. I also use it for two mechanism claims: blocking toxin binding at the brush border, and being usable alongside antibiotics because it is a yeast. The region is limited to China, so the trials pooled are not global, but pooled data beats a single trial.

[2] Nyssen OP, Jonaitis L, Pérez-Aísa Á, et al. (2026). Real-world effectiveness and safety of Saccharomyces boulardii CNCM I-745 as adjunct therapy for Helicobacter pylori eradication: data from the European Registry on H. pylori Management (Hp-EuReg). Helicobacter. 31(2):e70119. PMID: 41923280 Why chosen: Registry data, not a trial, so it is observational. It carries the H. pylori claim: adding CNCM I-745 raised eradication rates and cut side effects. It also gives me the phagosome maturation mechanism, which is in vitro, and the pharmaceutical-grade supplier detail. Registry evidence is messy by nature, but the sample is large and real-world, which is worth showing alongside the trials.

[3] Sjomina O, Poļaka I, Suhorukova J, et al. (2024). Randomised clinical trial: efficacy and safety of H. pylori eradication treatment with and without Saccharomyces boulardii supplementation. European Journal of Cancer Prevention. 33(3):217-222. PMID: 37942999 Why chosen: A randomised controlled trial on the same H. pylori question as the registry paper. Its role here is narrow and mostly safety: adding the yeast did not reduce eradication efficacy. I paired it with the registry study because one is controlled and the other is large, and they point the same way. It also supports the in vitro innate defense mechanism.

[4] Salazar-Parra MA, Cruz-Neri RU, Trujillo-Trujillo XA, et al. (2023). Effectiveness of Saccharomyces boulardii CNCM I-745 probiotic in acute inflammatory viral diarrhoea in adults: results from a single-centre randomized trial. BMC Gastroenterology. 23(1):229. PMID: 37400812 Why chosen: A single-centre randomised trial in adults with acute inflammatory viral diarrhea. It showed lower inflammatory markers and shorter symptoms. Single centre is a real limitation, and the population is narrow. I also use it for the celiac and mucosal barrier point, which the citing text marks as in vitro or ex vivo, so that part is not human evidence.

[5] Kan KR, Constante M, Rahmani S, et al. (2026). Saccharomyces boulardii CNCM I-745 synergizes with the small intestinal microbiota to boost AhR signaling in celiac disease. Gut Microbes. 18(1):2664640. PMID: 42068034 Why chosen: A 2026 journal article on AhR signaling in celiac disease. It is not tagged as a trial or review, so I read it as primary lab work. My source data shows no citing sentence attached to it, which means it is listed but not yet used in the body text. I kept it because the AhR and celiac angle appears in the mechanism discussion and needs a source behind it.

[6] Pontier-Bres R, Czerucka D. (2026). Saccharomyces boulardii CNCM I-745 stimulates intracellular antimicrobial activity against Salmonella Typhimurium in murine macrophages. Microorganisms. 14(4):787. PMID: 42075185 Why chosen: Murine macrophages, so this is animal and cell work. It supports the intracellular antimicrobial activity claim against Salmonella. No citing sentence is attached to it in my data, so it is a supporting reference rather than a load-bearing one. I included it because the immune mechanism section needed something concrete behind the word antimicrobial.

[7] Pais P, Oliveira J, Almeida V, et al. (2021). Transcriptome-wide differences between Saccharomyces cerevisiae and Saccharomyces cerevisiae var. boulardii: clues on host survival and probiotic activity based on promoter sequence variability. Genomics. 113(2):530-539. PMID: 33482324 Why chosen: A genomics and transcriptomics paper, cited six times, nearly all in Biology. It is where the CNCM registration, the Saccharomycetaceae and Ascomycota placement, the stress resistance and iron acquisition genes, the failure to form ascospores at 37°C, resistance to bile salts and pancreatic enzymes, and the tropical fruit origin all come from. It is also the reason I can say the strain differs from ordinary baker’s yeast. No clinical content, and I do not use it for any.

[8] Cifuentes SG, Prado MB, Fornasini M, et al. (2022). “Saccharomyces boulardii CNCM I-745 supplementation modifies the fecal resistome during Helicobacter pylori eradication therapy.” Helicobacter. 27(2):e12875. PMID: 34990038 Why chosen: Cited once, for reduced antibiotic resistance gene carriage during H. pylori therapy. PubMed lists it only as a journal article, without a trial tag, so I did not label it an RCT in the body. It is a resistome finding, which is a surrogate marker rather than a clinical outcome. I kept it because antibiotic resistance is a concrete public health angle and it pairs naturally with the two H. pylori papers above.

[1] Kruis W, Fric P, Pokrotnieks J, et al. (2004). Maintaining remission of ulcerative colitis with the probiotic Escherichia coli Nissle 1917 is as effective as with standard mesalazine. Gut. 53(11):1617-1623. PMID: 15479682 Why chosen: A multicentre randomised controlled trial, and the classic one for this strain. It tested EcN against mesalazine, a real drug, for keeping ulcerative colitis in remission, and reported equivalence at P = 0.003. It is old (2004) and the design is a non-inferiority comparison, which has known weaknesses. I still lead with it because a head-to-head against standard care is stronger evidence than a placebo comparison, and it anchors the regulatory approvals listed under Available products.

[2] Park SK, Kang SB, Kim S, et al. (2022). Additive effect of probiotics (Mutaflor) on 5-aminosalicylic acid therapy in patients with ulcerative colitis. Korean Journal of Internal Medicine. 37(5):949-957. PMID: 36068716 Why chosen: A multicentre randomised controlled trial from 2022, so it updates the 2004 result with modern endpoints. It found Mutaflor added to 5-ASA improved clinical response and mucosal healing versus 5-ASA alone. I cite it only for that. Having two independent multicentre trials eighteen years apart pointing the same way is the main reason the ulcerative colitis claim is stated as confidently as it is.

[3] Loffredo L, Alfano AR, Ettorre E, et al. (2025). Effect of the probiotic Escherichia coli Nissle 1917 on serum levels of NADPH oxidase-2 and lipopolysaccharide in patients with Alzheimer’s disease. Journal of Alzheimer’s Disease. 106(2):774-782. PMID: 40420691 Why chosen: A randomised controlled trial in Alzheimer’s patients, cited for systemic anti-inflammatory effects. The endpoints are biomarkers (NADPH oxidase-2 and LPS), not cognition or symptoms, so it does not show the strain treats Alzheimer’s. I included it because it is the only human signal here outside the gut, and I kept the claim at the level of inflammation.

[4] Gurbatri CR, Radford GA, Vrbanac L, et al. (2024). Engineering tumor-colonizing E. coli Nissle 1917 for detection and treatment of colorectal neoplasia. Nature Communications. 15(1):646. PMID: 38245513 Why chosen: Tagged as a clinical trial and multicentre study, on engineered EcN for colorectal neoplasia. My data has no citing sentence for it, so it is listed but not quoted in the body. I kept it because the tumor-homing and engineering discussion below depends on this line of work existing, and this is the highest profile paper of that group.

[5] Vaghela P, Dave B, Dabhade A, et al. (2026). Redrawing the gut map: evolving probiotic approaches to microbiota modulation in inflammatory bowel disease. Antonie Van Leeuwenhoek. 119(3):51. PMID: 41644858 Why chosen: A 2026 review, not primary data. I use it for four things: enhanced mucosal innate immunity, the tumor-homing mechanism, acceptable safety and preliminary anti-tumor activity from a Phase I trial, and the point that engineered versions are not commercially available. Because it is a review, every one of those claims is secondhand. It earns its place by covering the engineered-strain frontier that the older trials do not touch.

[6] Sun J, Gunzer F, Westendorf AM, et al. (2005). Genomic peculiarity of coding sequences and metabolic potential of probiotic Escherichia coli strain Nissle 1917 inferred from raw genome data. Journal of Biotechnology. 117(2):147-161. PMID: 15823404 Why chosen: A comparative genomics study from 2005, cited nine times and almost entirely in Biology and Mechanism. It explains why a bacterium normally considered risky can be used as a probiotic: no Shiga toxin, no intimin, no hemolysin, no enterotoxins, plus the K5 capsule driving serum resistance and colonization. It is old and based on raw genome data, but it is the reason the safety argument exists.

[7] Puurunen MK, Vockley J, Searle SL, et al. (2021). Safety and pharmacodynamics of an engineered E. coli Nissle for the treatment of phenylketonuria: a first-in-human phase 1/2a study. Nature Metabolism. 3(8):1125-1132. PMID: 34294923 Why chosen: A first-in-human phase 1/2a randomised trial, cited for proof of concept that probiotics can be engineered to do metabolic work. Phase 1/2a is about safety and dosing, not efficacy, so this is not evidence the approach works clinically. I included it because it is the strongest single example of where EcN research is heading, and a phase 1/2a trial is still human data.

[8] Olbertz D, Proquitté H, Patzer L, et al. (2023). Potential Benefit of Probiotic E. coli Nissle in Term Neonates. Klinische Pädiatrie. 235(4):213-220. PMID: 36446590 Why chosen: A randomised controlled trial in term neonates, cited for suggested benefit on gut colonization. The title says potential, which matches how I hedged it. Neonates are a sensitive population and giving a live E. coli product to newborns deserves caution. I kept the claim small and marked it as a suggestion.

[1] Wickens K, Barthow C, Mitchell EA, et al. (2018). Effects of Lactobacillus rhamnosus HN001 in early life on the cumulative prevalence of allergic disease to 11 years. Pediatric Allergy and Immunology. 29(8):808-814. PMID: 30430649 Why chosen: A multicentre randomised controlled trial with follow-up to age 11, which is rare. It is the source for the strongest claim in the entry: sustained allergy prevention across the first decade of life. I also use it for the Th2 skew mechanism and the global distribution note. Long follow-up is the main reason it earns the top slot. The outcome is cumulative prevalence of allergic disease, which bundles several conditions, so the effect on any single one is less certain.

[2] Wickens K, Barthow C, Mitchell EA, et al. (2018). Maternal supplementation alone with Lactobacillus rhamnosus HN001 during pregnancy and breastfeeding does not reduce infant eczema. Pediatric Allergy and Immunology. 29(3):296-302. PMID: 29415330 Why chosen: The same group’s negative trial, and I included it deliberately. Maternal supplementation alone did not cut infant eczema. That result is what lets me say direct infant exposure matters, rather than exposure through the mother. A null result from the same team that reported the positive one makes the whole entry more honest.

[3] Slykerman RF, Hood F, Wickens K, et al. (2017). Effect of Lactobacillus rhamnosus HN001 in pregnancy on postpartum symptoms of depression and anxiety: a randomised double-blind placebo-controlled trial. EBioMedicine. 24:159-165. PMID: 28943228 Why chosen: A double-blind placebo-controlled randomised trial, cited for lower postpartum depression and anxiety scores on the Edinburgh Postnatal Depression Scale. This is the most unexpected claim in the entry, so it needed a properly blinded trial behind it. The endpoint is a symptom scale, not a diagnosis, and mood outcomes are noisy. I state the finding and stop there.

[4] Ulluwishewa D, Purba A, Fegan V, et al. (2026). Lacticaseibacillus rhamnosus HN001 enhances intestinal barrier function and protects the blood-brain barrier from inflammatory disruption in vitro. Frontiers in Physiology. 17:1808663. PMID: 42180834 Why chosen: An in vitro study, labelled as such in both sections where it appears. It shows better intestinal barrier function and protection of blood-brain barrier integrity under inflammatory conditions. Cells in a dish are a long way from a person, so this supports plausibility for the mood findings rather than proving them. I kept it because the barrier mechanism is otherwise unclaimed.

[5] Murphy R, Morgan XC, Wang XY, et al. (2019). Eczema-protective probiotic alters infant gut microbiome functional capacity but not composition: sub-sample analysis from a RCT. Beneficial Microbes. 10(1):5-17. PMID: 30574802 Why chosen: A sub-sample analysis from a randomised trial, which I flagged as a substudy. Its finding is interesting and specific: the probiotic changed what the infant microbiome could do, not which bacteria were there. That is why I describe the effect as metabolic reprogramming rather than a compositional shift. Sub-sample means fewer participants and more chance of a chance finding.

[6] Ceapa C, Lambert J, van Limpt K, et al. (2015). Correlation of Lactobacillus rhamnosus genotypes and carbohydrate utilization signatures determined by phenotype profiling. Applied and Environmental Microbiology. 81(16):5458-5470. PMID: 26048937 Why chosen: A phenotype profiling study, cited seven times, mostly in Biology and Mechanism. It is the source for the strain-level differences between HN001 and its relatives, the distinct carbohydrate utilization phenotype, bile and acid tolerance, no gas from glucose, mucosal colonization behavior, and isolation from dairy and the human gut. It explains why I insist on strain names instead of species names. No clinical data.

[7] Zheng J, Wittouck S, Salvetti E, et al. (2020). A taxonomic note on the genus Lactobacillus: description of 23 novel genera, emended description of the genus Lactobacillus Beijerinck 1901, and union of Lactobacillaceae and Leuconostocaceae. International Journal of Systematic and Evolutionary Microbiology. 70(4):2782-2858. PMID: 32293557 Why chosen: The 2020 reclassification paper that moved rhamnosus into the new genus Lacticaseibacillus. It is taxonomy only, cited twice in Overview and Biology. I include it so the older trials labelled Lactobacillus rhamnosus HN001 and the current name are visibly the same organism. Note the citation string is truncated in my source data; I copied it as given.

[8] Juvale IIA, Arulsamy A. (2025). “The therapeutic effects of Lacticaseibacillus rhamnosus on stress-induced anxiety: a systematic review of evidence from animal studies.” Gut Microbiome. 6:eXX. PMID: 41497537 Why chosen: Tagged as a review, and its title says the evidence comes from animal studies. That is the weakest tier here, and I cite it only in the stress-induced anxiety discussion. I kept it because a systematic review at least gathers the animal literature in one place, but the findings cannot be carried over to people. The journal page number is recorded as eXX in my source, which I left as is.