Effects of combined gamma aminobutyric acid supplementation and exercise training on the body composition of women: A randomized double-blind trial

Background: Preclinical and clinical investigations have revealed the metabolic health benefits of gamma-aminobutyric acid (GABA) supplementation. Exercise training is widely acknowledged for its positive effects on the health of individuals with obesity. Objective: To investigate the effects of combined GABA supplementation and exercise training on the body composition, nutritional intake, physical performance, and serum biomarkers of women with obesity. Methods: Twenty-six women with obesity were investigated in this randomized, double-blind, placebo-controlled trial. They received daily GABA (200 mg) supplementation for 90 days alongside exercise training (3 days/week). Results: For intragroup comparisons hand grip improved in both groups (placebo, p = 0.00276; GABA, p = 0.00012), while sit-up performance increased only in the GABA group (p = 0.00664). Body mass index (p = 0.01273) and waist circumference (p = 0.01393) decreased in the GABA group. In the placebo group, body mass (p = 0.02956), fat-free mass (p = 0.00344), and basal metabolic rate (BMR) (p = 0.00386) decreased, while body fat increased (p = 0.02666). There were no differences in daily macronutrient intake, BMR, body mass, body fat, fat mass, fat-free mass, hip circumference, waist-hip ratio, blood pressure, heart rate, or serum levels of glucose, triglycerides, leptin, resistin, chemokine (C-C motif) ligand 2, chemokine ligand 16, and growth hormone between groups. Conclusion: GABA supplementation combined with exercise training enhanced physical performance, accompanied by modest improvements in body composition, with no adverse effects on nutritional, physiological, or blood serum parameters. Study registration: https://ensaiosclinicos.gov.br/rg/RBR-8t7h259. (c) 2025 Published by Elsevier Ltd on behalf of European Society for Clinical Nutrition and Metabolism.