Can Probiotics Help With Weight Loss?

What the research shows

Multiple high-quality studies including systematic reviews and randomized controlled trials indicate that probiotics alone may have little to no significant effect on BMI, body weight, waist circumference, or body fat in children, adolescents, and adults with overweight or obesity. Some evidence suggests that prebiotics, synbiotics, and short-chain fatty acids (SCFAs) might contribute to small reductions in BMI, body weight, waist circumference, and systolic blood pressure, but the certainty of this evidence is very low due to small sample sizes and limited studies. Specific Lactobacillus strains have shown mixed results, with some strains associated with weight loss and others with no effect or weight gain, highlighting the importance of strain specificity. Synbiotic supplementation combined with weight loss programs may modulate gut microbiota and improve metabolic markers but does not consistently enhance weight loss outcomes. Probiotic supplementation alongside caloric restriction did not significantly improve weight loss compared to caloric restriction alone but may improve anxiety and depressive symptoms. Overall, probiotics and synbiotics may support weight management as part of a multifaceted approach but are not standalone solutions for weight loss.

Best studied probiotic strains

Who may benefit

Safety

Probiotic, prebiotic, synbiotic, and SCFA interventions were generally safe with low incidence of mild adverse events such as abdominal discomfort, nausea, headache, and migraine reported in some studies.

Limitations

Evidence is limited by very low certainty due to small sample sizes, short intervention durations, heterogeneity of probiotic strains and formulations, lack of strain-specific data in many studies, and insufficient reporting of adverse events. Many studies combined probiotics with other interventions, making it difficult to isolate effects. More rigorous, longer-term, strain-specific trials are needed.

PubMed sources