Research

Mixed

Probiotic supplementation in overweight or obese adults produces a statistically significant but clinically small reduction in body weight, BMI, and fat percentage compared to placebo.

If you are overweight or obese, adding probiotics may help you lose a tiny amount of extra weight (about 0.6 kg) compared to not taking them. Do not rely on probiotics for weight loss; focus on diet and exercise first, as the probiotic effect is negligible in isolation.

GoodQualifiesHIGH confidence
Administration of probiotics resulted in a significantly larger reduction in body weight (weighted mean difference [95% confidence interval]; -0.60 [-1.19, -0.01] kg, I2 = 49%), BMI (-0.27 [-0.45, -0.08] kg m-2, I2 = 57%) and fat percentage (-0.60 [-1.20, -0.01] %, I2 = 19%), compared with placebo; however, the effect sizes were small.
Heidi Borgeraas et al. · Obesity Reviews · 2017

Why this rating

Systematic review and meta-analysis of 15 RCTs, though heterogeneity was moderate to high.

Source

Effects of probiotics on body weight, body mass index, fat mass and fat percentage in subjects with overweight or obesity: a systematic review and meta‐analysis of randomized controlled trials

Heidi Borgeraas et al. · Obesity Reviews · 2017

DOI 10.1111/obr.12626

Meta-analysis · 15 studiesCited 265×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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