Effect of Medium Chain Fatty Acids on Body Composition in Individuals with Overweight and Obesity: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the effects of medium-chain triacylglycerol (MCT) intake on the body composition of individuals with overweight and obesity through a systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: PubMed, Cochrane Library, and Embase databases were searched until January 2026. The primary outcome was the change in fat mass (FM) between the MCT intake and control groups; secondary outcomes included body weight (BW), waist circumference (WC), and lean mass (LM). Pooled effect sizes were estimated using random-effects models, and certainty was assessed using GRADE (Grading of Recommendations Assessment, Development and Evaluation). RoB-2 was used for assessing risk of bias. RESULTS: Seven RCTs (N = 346) were included in this study. MCT intake significantly reduced FM (SMD: -0.42; 95% CI: -0.67 to -0.17), BW (SMD: -0.41; 95% CI: -0.64 to -0.18), and WC (SMD: -0.42; 95% CI: -0.69 to -0.14) compared to controls, with no significant effect on LM. Heterogeneity was low (I2 = 0%), although the certainty of the evidence was low. Sensitivity analyses for BMI ≧ 25 kg/m2 confirmed these findings. Adverse events associated with MCT intake are rare and well-tolerated. CONCLUSION: MCT intake effectively and safely reduced body fat and waist circumference while preserving lean mass, suggesting its value in obesity management.