Promoted relaxation

• In 2006 Biofactors published a cross-over study in which 13 subjects who consumed GABA had significant increases in alpha brain waves and decreases in beta waves compared to water or l-theanine. The changes in brain wave activity indicates that GABA induces relaxation and reduces anxiety. An additional placebo-controlled study involving 8 participants showed that GABA was able to enhance immunity during high-stress situations. [Source]

Boost growth hormone levels

• In 2008 Medicine and Science in Sports and Exercise published a double-blind, cross-over study in which 11 resistance-trained participants consumed 3 grams of GABA or a placebo before resistance training. Thirty minutes after ingestion of GABA (combined with exercise) growth hormone levels increased by up to 200 percent more than exercise alone. [Source]