Probiotics for Prosperity: Is There a Role for Probiotics in the Fight Against Obesity? Review of Meta-Analyses of Randomized Controlled Trials

Abstract

Purpose: Obesity is a chronic disease that is acquiring pandemic proportions. Emerging research suggests that probiotics can be a valuable yet still an underutilized modality for obesity treatment. This review aims to analyze and summarize recent data focusing on published meta-analyses of randomized controlled trials (RCTs) to help understand the role of probiotics in fighting obesity. Materials and Methods: Meta-analyses were sought and reviewed from PubMed, Cochrane Central Library, ScienceDirect, and Google Scholar for body weight and/or BMI changes (two main outcomes of interest). Results: The literature review identified 14 meta-analyses. On average, the meta-analyses dedicated to probiotics included 4-15 trials with 154-994 participants, whereas more inclusive probiotics and/or synbiotics analyses included 15-68 trials with 895-4015 participants. Eleven out of 14 meta-analyses showed that probiotic use in RCTs resulted in reduced body weight and/or BMI compared to placebo. An average weight loss was 0.6 kg, and the most substantial loss was 4.8 kg corresponding to 0.7% and 5.9% reductions in body weight, respectively. Probiotics' use was associated with improved health outcomes in addition to weight loss and was safe. The subgroup analyses showed that the probiotic forms (supplements vs food) and the dosages (lower vs higher than 10 10 CFU/day) did not substantially influence weight loss. The single species particularly helpful for weight loss appeared to be L. gasseri, L. casei, L. delbrueckii, L. reuteri, L. rhamnosus, a combination of L. curvatus and L. plantarum and Bobacterium longum. Bacillus subtilis and Akkermansia muciniphila also had a potential as anti-obesity probiotics. Conclusion: Probiotics, despite small effects, could be a valuable addition to the armamentarium of obesity management. Further basic and translational research and clinical trials are required to elucidate mechanisms and specific probiotic and patients' types for the best achievable precision medicine approach to the obesity epidemic.