When a supplement is recommended for “rest and relaxation”, you may immediately assume it is something that will make you sleepy. But what about when you need to relax but stay focused? Or relax in a stressful situation? Relax when it’s not time to sleep? Gamma aminobutyric acid (GABA) might be just the supplement to support you in times of anxiety. Of course, it may also help you sleep when the time is right, too…

What is Gaba?

GABA is a naturally occurring neurotransmitter that controls brain activity in a variety of ways and regulates muscle tone throughout the body. Unlike other neurotransmitters, GABA has an inhibitory function: it slows down neuron firing [1]. Most neurotransmitters (such as adrenaline) have an excitatory function and tend to stimulate neuron firing. When GABA levels are low, neurons fire too easily and too often which can stimulate anxiety, insomnia, and even seizures [2]. It has been reported that circulating natural GABA levels are lower than normal in people suffering from depression and mood disorders and have been measured to be as much as 30% lower in people experiencing insomnia [3,4]. 

Can Gaba help with sleep?

GABA supplementation is thought to have a natural calming effect and may reduce feelings of anxiety and fear by decreasing neuronal excitability. As a natural supplement, GABA is most known for promoting sleep, balancing mood, reducing stress, alleviating pain, and easing premenstrual symptoms. In fact, many Western medications prescribed to patients suffering from anxiety (Valium/Diazepam, Xanax/Alprazolam, etc.) are designed to target GABA receptors and mimic GABA’s action in the brain. 

How does Gaba work on the brain?

You may be wondering why there are drugs designed to act like GABA if we can just supplement with natural GABA to build up depleted GABA. This is a great question, but the answer is tricky. GABA is a natural chemical that scientists are working to understand. It is not a designer drug that has been engineered to treat a problem. However, recent studies are making great strides in clarifying the mechanism of action for GABA. GABA has been researched for decades and has a history of conflicting evidence in terms of whether or not supplementary GABA crosses the blood-brain barrier. Most recently, it has been found that there are GABA transporters on the human blood-brain barrier, so it is likely that at least some of its effects are due to direct interaction with the brain [2]. Other effects may be a secondary interaction with the brain, with the enteric nervous system (ENS) acting as an intermediary. The ENS is the network of nerves controlling the gastrointestinal system, but it regularly communicates with the brain via the vagus nerve. The ENS contains an abundance of GABA receptors and may also be how supplementary GABA elicits effects [2].

Regardless of whether GABA’s effect on the brain is direct or secondary, via the ENS, it is clear that the brain responds to it. One study, which was focused on brain waves, measured electroencephalograms (EEG) 60 minutes after administration and showed that, in those who took GABA supplements, alpha waves significantly increased and beta waves significantly decreased compared to participants who just drank water or supplemented with L‐theanine. These are quantitative measurements providing evidence that GABA induced relaxation as well as anxiety [5]. 

Data from a similar EEG study measured brain activity in relation to “mental stress task loads”, and the condition of participants 30 min after GABA intake. Compared to a placebo, GABA supplementation was associated with a diminished decrease in alpha brain waves compared with the placebo condition [6]. Again this method quantitatively measured an alleviation of stress from mental tasks, likely in response to GABA. This effect also corresponded with the results of Profile of Mood State (POMS) scores, which is a qualitative psychological test for mood and state of mind [6].

Another study investigating the relaxant and anxiolytic effects of GABA on immunity in stressed volunteers, involved acrophobic (afraid of heights) participants crossing a suspended bridge to stimulate stress responses. Immunoglobulin A (IgA) levels in saliva rose significantly in those who had taken GABA, suggesting GABA was not only an effective natural relaxant within 1 hour of administration, but it also enhanced immunity under stress conditions [5].

Again, GABA is not an anti-anxiety (anxiolytic) drug. It is not a sleep aid, it is not an antidepressant, and the intention of supplementation is not to cure or treat any of the aforementioned problems. However, if you think your GABA levels might be low, and you are interested in some natural support that may help to balance your mood and boost your immune system in times of stress, talk to your physician about adding a GABA supplement to your health routine. Then sit back and relax!


  1. Bowery, N. G., and T. G. Smart. “GABA and glycine as neurotransmitters: a brief history.” British journal of pharmacology 147.S1 (2006): S109-S119.
  2. McVean, Ada. “GABA supplements: glorious, gimmicky or just garbage?” McGill Office for Science and Society. Oct 11, 2018. https://www.mcgill.ca/oss/article/health/gaba-supplements-glorious-gimmicky-or-just-garbage
  3. Winkelman, John W., et al. “Reduced brain GABA in primary insomnia: preliminary data from 4T proton magnetic resonance spectroscopy (1H-MRS).” Sleep 31.11 (2008): 1499-1506.
  4. Luscher, Bernhard, Qiuying Shen, and Nadia Sahir. “The GABAergic deficit hypothesis of major depressive disorder.” Molecular psychiatry 16.4 (2011): 383.
  5. Abdou AM, et. al; Relaxation and immunity enhancement effects of gamma-aminobutyric acid (GABA) administration in humans. Biofactors. 2006;26(3):201-8.
  6. Yoto, A., et al. “Oral intake of γ-aminobutyric acid affects mood and activities of central nervous system during stressed condition induced by mental tasks.” Amino Acids 43.3 (2012): 1331-1337.