Research

Mixed

Oral intake of bacterial probiotics (specifically multispecies mixes containing Bifidobacterium breve, B. longum, Streptococcus salivarius subsp. thermophilus, Lactobacillus acidophilus, L. casei, or L. delbrueckii) induces minor but statistically significant reductions in body weight, BMI, waist circumference, and visceral adipose tissue in overweight (but not obese) subjects.

If you are overweight, adding a multispecies probiotic supplement (containing strains like L. acidophilus or B. breve) to your daily routine may help you lose a small amount of weight (less than 1 kg on average) and reduce waist size over 8 weeks. This effect is not seen in obese individuals. Do not rely on probiotics alone for weight loss; use them as a minor adjunct to diet and exercise.

GoodQualifiesMEDIUM confidence
In overweight but not obese subjects, probiotics induced improvements in: body weight (k=25 trials, d=−0.94 kg mean difference...), body mass index (k=32, d=−0.55 kg/m²...), waist circumference (k=13, d=−1.31 cm...), body fat mass (k=11, d=−0.96 kg...), and visceral adipose tissue mass (k=5, d=−6.30 cm²...)
Hana Koutníková et al. · BMJ Open · 2019

Why this rating

Large meta-analysis (6826 subjects) of RCTs, but robustness is heavily dependent on trials from a single country (Iran), raising generalizability concerns.

Source

Impact of bacterial probiotics on obesity, diabetes and non-alcoholic fatty liver disease related variables: a systematic review and meta-analysis of randomised controlled trials

Hana Koutníková et al. · BMJ Open · 2019

DOI 10.1136/bmjopen-2017-017995

Meta-analysis · 99 studiesCited 300×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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