Effects of dietary interventions on gut microbiota and related cardiometabolic changes in pediatric obesity: a systematic review and meta-analysis.
BACKGROUND: Gut microbiota imbalances may contribute to obesity, yet whether dietary interventions can modulate the microbiota and improve metabolic health in pediatrics has not been thoroughly reviewed. This systematic review and meta-analysis explores the impact of dietary interventions on the gut microbiota of children and adolescents with overweight or obesity, and its association with cardiometabolic improvements. METHODS: A systematic search of clinical trials in Pubmed, Cochrane and EMBASE was conducted following PRISMA guidelines (PROSPERO n°CRD42024505494). Risk of bias was assessed with RoB2 and ROBINS, for randomized and non-randomized intervention studies. RESULTS: Overall, 60 articles were assessed for full-text eligibility, 8 were included, and 4 provided alpha-diversity data for meta-analysis. A total of 200 participants were included (6-16 years). Six studies implemented calorie-restricted diets, one a low free-sugar diet, and one CHILD-1 diet. The meta-analysis revealed a significant increase in Chao1 (48.76 [95%CI 1.81; 95.70]; I2 = 86.8%, p < 0.001) following a balanced calorie-restricted dietary intervention. Although there was heterogeneity in taxa-level changes, several butyrate-producing genera (Clostridium XVIa, Coprococcus, Roseburia, Faecalibacterium, Blautia, Butyricimonas) increased following dietary intervention. CONCLUSIONS: Balanced dietary interventions with calorie-restriction adequate for pediatric age could increase gut microbiota richness and butyrate-producing bacteria abundance. Future trials should clarify diet-driven gut microbiota changes in childhood obesity and related metabolic changes. IMPACT: Balanced calorie restriction diet may increase gut microbiota richness in childhood obesity Butyrate-producer expansion needs long-term dietary intervention Gaps in linking microbiota-metabolism interplay in pediatric obesity.