Gamma-aminobutyric acid, or GABA, is a neurotransmitter that helps regulate anxiety. Low GABA levels are associated with depression and anxiety disorders. A 2007 study found that a single yoga session significantly increased GABA levels in participants, and a follow-up compared yoga to walking over 12 weeks.
The yoga group showed a 27% increase in GABA levels. The walking group showed no significant change. Both groups exercised for the same duration. The difference appears to be linked to the specific combination of breath control, physical postures, and internal focus that yoga requires.
This finding has implications for understanding why yoga practitioners often report feeling calmer after practice. It is not merely a subjective impression. There is a measurable neurochemical shift occurring, one that pharmaceutical interventions also target, though through a different mechanism.
Source: Yoga Research: Brain Structure & Function on ashtanga.tech. Original research.