Efficacy of Probiotics in Overweight and Obesity Control: An Umbrella Review and Subgroup Meta-Analysis

Numerous primary and secondary studies have consistently demonstrated that probiotics, including lactobacillus and Bifidobacterium, possess a potential anti-obesity effect. However, it is worth noting that some studies have yielded contrasting results. Considering this, our study aims to present a comprehensive overview of published systematic reviews and meta-analyses, focusing on the efficacy and safety of probiotics in managing obesity. To achieve this objective, we conducted an umbrella review following the PRISMA protocol and Cochrane guidelines. We searched databases such as Embase, PubMed, Cochrane Library, and Google Scholar for relevant systematic reviews and meta-analyses published in English, without imposing any date restrictions. Our inclusion criteria encompassed studies evaluating the anti-obesity impact of probiotics, with a specific focus on changes in body mass index (BMI), fat mass percentage (FMP), body weight (BW), and body fat mass (BFM). These studies were meticulously reviewed by two independent reviewers. Our analysis included five systematic reviews and 18 meta-analyses that met the predefined inclusion and exclusion criteria. The meta-analyses revealed statistically significant reductions in the following parameters: BMI, a decrease of 0.30 kg/m² (p < 0.00001, 95% CI - 0.36 to - 0.25); BFM, a reduction of 0.86 kg (p < 0.00001, 95% CI - 1.02 to - 0.71); BW, a decrease of 0.59 kg (p < 0.00001, 95% CI - 0.74 to - 0.44); and FMP, a substantial decline of 78% (p < 0.00001, 95% CI - 1.02 to - 0.54). In summary, our umbrella review suggests that existing evidence supports the potential benefits of probiotics in managing obesity and overweight. However, it is essential to acknowledge that the credibility of this evidence is somewhat limited due to the inclusion of studies with poor-quality designs and relatively small participant numbers. To establish the true efficacy of probiotics in obesity management, we recommend conducting robust studies involving larger participant cohorts.