Probiotic

    Lactobacillus Gasseri

    Lactobacillus gasseri

    TL;DR

    L. gasseri produced small reductions in abdominal fat in Japanese and Korean trials, but the effect faded after stopping and has not replicated well elsewhere. Modest at best.

    Ideal For

    • People already dieting who want a marginal metabolic nudge
    • Those seeking urogenital flora support

    Avoid If

    • You expect meaningful weight loss from a capsule
    • You are immunocompromised
    • You will not sustain it - the effect reverses on stopping

    Frequently Asked Questions

    Overview

    Lactobacillus gasseri is a native human gut and vaginal commensal that reached supplement shelves on the back of body-composition research. The most cited work is a 12-week Japanese trial of strain SBT2055 in 210 adults with elevated visceral fat: fermented milk containing the strain reduced visceral fat area by roughly 8% versus control, alongside small drops in waist circumference and body weight. A follow-up showed the effect reversed within four weeks of stopping.

    Korean trials of strain BNR17 report similar direction and magnitude - about 1-2 cm of waist and small visceral fat reductions over 12 weeks. Independent replication outside East Asian cohorts is thin, and effect sizes are far below anything a diet change would produce.

    Separate literature covers vaginal and urogenital health, where L. gasseri is a dominant healthy-flora species, but supplement trials there are small.

    How It Works

    • Reduces dietary fat absorption and increases faecal fat excretion
    • Lowers low-grade inflammatory signalling in adipose tissue
    • Modulates bile-salt hydrolase activity, altering lipid handling
    • Restores lactobacilli dominance in the vaginal microbiome

    Benefits & Outcomes

    Weight Loss Support

    Metabolic
    Mixed evidence
    Limited
    Effectiveness 2/5

    A marginal nudge at best. Real, measurable, and far smaller than any dietary change worth making.

    Health Concerns Addressed

    No linked health concerns yet.

    Supporting Research
    5 studies

    Regulation of abdominal adiposity by probiotics (Lactobacillus gasseri SBT2055) in adults with obese tendencies in a randomized controlled trial

    Score: 7/10
    2010
    rct
    n=87

    Kadooka Y, Sato M, Imaizumi K +6 more

    Visceral and subcutaneous fat areas decreased significantly with LG2055 compared with control, alongside reductions in body weight and waist circumference.

    View source

    Effect of Lactobacillus gasseri SBT2055 in fermented milk on abdominal adiposity in adults in a randomised controlled trial

    Score: 7/10
    2013
    rct
    n=210

    Kadooka Y, Sato M, Ogawa A +6 more

    Both lower probiotic doses reduced visceral fat area by around 8 percent compared with control, with reductions in body weight and BMI.

    View source

    Effects of Lactobacillus gasseri BNR17 on overweight and obese adults: a randomized, double-blind clinical trial

    Score: 7/10
    2018
    rct
    n=90

    Kim J, Yun JM, Kim MK +2 more

    Body weight and BMI did not differ significantly from placebo; only waist and hip circumference showed small reductions in the high-dose group.

    View source

    Lactobacillus gasseri and Helicobacter pylori eradication: a randomized controlled trial of supplementation to standard triple therapy

    Score: 6/10
    2012
    rct
    n=229

    Deguchi R, Nakaminami H, Rimbara E +9 more

    Eradication rates were higher with adjunct L. gasseri yogurt than triple therapy alone, with fewer gastrointestinal side effects.

    View source

    Outcome-Specific Efficacy of Different Probiotic Strains and Mixtures in Irritable Bowel Syndrome: A Systematic Review and Network Meta-Analysis

    Score: 7/10
    2023
    meta_analysis

    Zhang T, et al.

    Efficacy in irritable bowel syndrome differs markedly between probiotic strains and mixtures depending on the outcome assessed.

    View source

    Safety Information

    Potential Side Effects

    Mild bloating or gas early on; otherwise well tolerated in 12-week trials.

    Contraindications

    Avoid in severe immunosuppression, critical illness or with central venous access.

    Drug Interactions

    • Antibiotics reduce viability - separate by 2 hours

    Pregnancy & Breastfeeding

    Pregnancy: insufficient_data

    Breastfeeding: insufficient_data

    Dosage Guidelines

    Dosage Used in Studies

    Consult healthcare provider

    Best Time to Take

    Once daily with a main meal

    Best Form

    Named strain BNR17 or SBT2055

    Dosing by Goal

    GoalDoseNotes
    10 billion CFU/day12-week trial duration; benefits reverse after stopping
    1-10 billion CFU/daySmall trials; often combined with L. rhamnosus

    Forms Compared

    Strain used in the Korean body-composition trials

    Strain from the Japanese visceral fat trial; hard to source outside Japan

    Food & Timing

    With a meal.

    Medical Disclaimer

    The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.

    Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.