Association between gut microbiota and pediatric obesity: A systematic review

Pediatric obesity is a multifactorial public health problem with increasing prevalence. Among the many contributing factors, the intestinal microbiota has emerged as a key area of investigation due to its potential role in metabolism, immunity, and energy regulation. Understanding and modulating the gut microbiota may offer novel therapeutic strategies. This systematic review aims to explore the relationship between the intestinal microbiota composition and obesity in pediatric age.

The review followed PRISMA recommendations. Two databases (PubMed and Scopus) were consulted in May 2024 for research and two independent reviewers screened abstracts, following extraction of relevant data. Risk of bias was assessed using the Cochrane Collaboration's RoB 2 and ROBIN-I tools.

This review included a set of 70 studies, of which 23 were clinical trials and 47 were cross-sectional studies. They all analyzed the intestinal microbiota using fecal DNA sequencing, comparing microbial and metabolomic profiles between normal-weight children and overweight children. The effects of current interventions, such as the use of probiotics, supplementation, physical activity, and fecal microbiota transplantation, are also explored. Despite variability in findings, certain genera-such as Akkermansia, Bifidobacterium, Blautia, and Faecalibacterium-emerged as frequently associated with obesity-related traits. The Firmicutes/Bacteroidetes ratio showed inconsistent associations.

Pediatric obesity is associated with distinct changes in gut microbiota composition and function. While promising, the current evidence is heterogeneous. Future research should focus on longitudinal designs and standardized methodologies to clarify the role of diet, physical activity, and microbiota-based therapies in obesity prevention and management.