Gamma Aminobutyric Acid (GABA) Clinical Evidence

Topic:
What are the effects of Gamma-aminobutryric acid (GABA) on relaxation and immunity?

Background:
GABA is a neurotransmitter that inhibits the firing of neurons and is considered a natural tranquilizer.

Study Type:
Human clinical intervention trial

Study Design:
Placebo-controlled. In the first phase of the study, researchers measured the brain waves of healthy subjects after they took GABA, L-Theanine or a placebo at baseline, and 30 and 60 minutes post-dose.In the second phase, subjects with acrophobia (fear of heights) took either GABA or a placebo and then crossed a suspension bridge. Levels of immunoglobin A (an antibody) in their saliva were measured during the stressful event.

Subjects:
13 healthy Japanese subjects and 8 acrophobic subjects

Dosage:
A single dose of 100 mg of GABA, 200 mg of Ltheanine or placebo

Results:
Alpha waves increased by approximately 50% and beta waves decreased by more than 50% in the healthy subjects. (Alpha waves indicate a state of relaxed alertness. Beta waves are generated during logical thought or when encountering new stimuli, but too much beta wave activity can indicate panic.) In the acrophobic group, IgA levels fell under stressful circumstances when subjects took a placebo. However, when they took GABA, IgA levels were significantly higher.

Conclusion:
GABA could work effectively as a natural relaxant and its effects could be seen within 1 hour of its administration and diminish anxiety. Moreover, GABA administration could enhance immunity under stress conditions.