Key Points
- Physical performance improved
- GABA reduced BMI and waist circumference
- Helped preserve lean muscle mass
- Resting metabolic rate remained stable
Methods
Twenty-six adult women with obesity were split into two groups for 12 weeks:
- GABA: received 200 mg GABA nightly before bed + 3 exercise sessions per week, for 90 days
- Placebo: received identical placebo capsules + 3 exercise sessions per week, for 90 days
Exercise plan included three sessions a week consisting of 20 min aerobic, 20 min resistance, and 10 minutes of flexibility training.
GABA Preserves Lean Mass and Reduces Waist Size
Women supplementing with GABA saw a reduction in body mass index (BMI) and a 2 cm decrease in waist circumference.
"GABA supplementation supported modest yet measurable improvements in body composition. Participants taking GABA showed reductions in body mass index and waist circumference."
The placebo group, despite completing the same training, gained body fat and lost lean mass.
"In contrast, those in the placebo group experienced a slight increase in body fat percentage and a loss of fat-free mass."
These results suggest that GABA may help protect muscle tissue during exercise, a period when lean mass often declines. Understanding the critical role of lean mass preservation provides important context for why interventions that protect muscle during weight loss can significantly impact metabolic health, functional capacity, and long-term healthspan outcomes.
Improves Strength and Physical Performance
Both groups improved grip strength, but GABA produced more consistent gains. Only GABA users increased core endurance, completing nearly 3 additional sit-ups in one minute.
"Hand-grip and sit-up performance increased significantly after GABA supplementation, indicating enhanced muscular performance."
These benefits were seen without changes in diet, pointing to GABA's direct influence on exercise and muscle function.
Supports Metabolic Stability
In the placebo group, basal metabolic rate, the energy your body uses at complete rest, decreased by ~35 kcal/day, suggesting their metabolism slowed. GABA users maintained energy expenditure.
"Resting metabolic rate declined in the placebo group, but remained stable in the GABA group, implying that supplementation may help preserve metabolic activity during modest weight loss or exercise adaptation."
"There were no adverse effects on nutritional, physiological, or blood serum parameters, confirming the safety of daily GABA supplementation."
Maintaining resting energy may help prevent loss of muscle and other lean tissue.
Conclusion
Healthy GABA levels appear important not only for mood and sleep but also for body composition, exercise performance, and metabolic resilience.
"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."
In women with obesity, low-dose GABA (200 mg/day) combined with moderate exercise safely improved strength and waistline measures while maintaining lean mass.
"GABA as a dietary supplement is capable of aiding exercise adherence, particularly among women with obesity… helping transition from a sedentary to a more active lifestyle."
GABA represents a promising adjunct for supporting healthy metabolism, muscle preservation, and physical performance during lifestyle change. Research on GABA's effects on sleep quality and stress reduction suggests that its benefits may extend beyond direct metabolic effects—improved sleep and reduced cortisol could contribute to better exercise recovery, enhanced muscle protein synthesis, and optimized body composition outcomes.
