Gamma-aminobutyric acid (GABA) is a neurotransmitter or a molecule that sends chemical messages in our brains. It can decrease nerve activity and offer a calming, relaxing effect. GABA is a popular and safe dietary supplement that helps with stress, anxiety, lack of sleep, and high blood pressure.
The recommended dosage of GABA is anywhere from 300 mg to 1 gram per day, for up to a month. The reported side effects were mild and only included sleepiness and headaches. Keep reading and find out more details on GABA supplementation in the rest of this article.
GABA - Health Benefits
GABA is a natural molecule present in our brains, that inhibits certain brain functions and decreases overall brain activity. This does not mean that GABA is dangerous or bad for our nervous system, it means that GABA regulates nerve functions and stops the brain from "overworking".
GABA is a messenger molecule in the brain, officially known as a neurotransmitter. This means that GABA "travels" from cell to cell, and binds itself to specific receptor proteins on cells' surfaces. Once this happens, GABA exerts its calming effect on the brain.
GABA helps with anxiety and stress
GABA is known for having a calming effect on people, and some even take it for seizures.
So far, some smaller studies have shown that GABA supplements indeed help with reducing stress. For example, a couple of hours after taking GABA-enhanced oolong tea, university students tested much better on stress scores (1).
GABA supplement for sleep
Having trouble falling asleep comes along with being stressed and anxious. The relaxing effect of GABA offers relief and reduces insomnia.
Several studies looked at the effect that isolated GABA has on sleep improvement, and found that doses as low as 150 mg per day were effective in improving sleep quality (2). Another study found that 300 mg of GABA per day was even more effective while remaining safe for use, with only minor side effects (3)
GABA lowers blood pressure
Lowering high blood pressure is one of the most known effects of GABA supplements. More than 10 studies done on human subjects have shown that GABA supplementation significantly lowers blood pressure in mild hypertensive or hypertensive patients.
GABA was supplemented either through enriched foods (like milk, rice, or soy), or through GABA powder in capsules (4). The blood pressure-lowering effects were usually monitored over 2 months, but they usually stopped right after the supplementation ended.
GABA - Dosage
You can take GABA supplements in the form of powder-filled capsules or through fermented food, like soy and yeast. However, it is much easier to control and calculate the dosage of isolated GABA in capsules.
Several clinical studies have shown that taking up to 3 grams of GABA per day is safe and effective. This dosage is usually split into three doses of 750 mg, and taken up to 4 weeks (3).
GABA Supplement - Side Effects
GABA is a safe supplement with only mild side effects reported so far. The side effects also depend on the amount of GABA you take, and they can be more severe if you take a very high amount (5-10 grams per day) at once.
Possible side effects of GABA are:
- sleepiness and fatigue,
- headache,
- stomach upset.
Right after you take an oral GABA supplement, you might feel some skin itching or tingling, This sensation might develop into your mouth burning, extremely low blood pressure, or a severe allergic reaction if you take excessive amounts of GABA.
Does a GABA supplement cause liver damage? It does not, and in turn it even has a protective effect on the liver (5, 6). Always talk to your doctor or healthcare provider before starting to take any new supplements, especially if you already take medication or if you are pregnant or breastfeeding.
Literature sources:
- Hinton T, Jelinek HF, Viengkhou V, Johnston GA, Matthews S. Effect of GABA-Fortified Oolong Tea on Reducing Stress in a University Student Cohort. Front Nutr. 2019 Mar 26;6:27. doi: 10.3389/fnut.2019.00027.
- Byun JI, Shin YY, Chung SE, Shin WC. Safety and Efficacy of Gamma-Aminobutyric Acid from Fermented Rice Germ in Patients with Insomnia Symptoms: A Randomized, Double-Blind Trial. J Clin Neurol. 2018 Jul;14(3):291-295. doi: 10.3988/jcn.2018.14.3.291.
- Yoon S, Byun JI, Shin WC. Efficacy and Safety of Low-Dose Gamma-Aminobutyric Acid From Unpolished Rice Germ as a Health Functional Food for Promoting Sleep: A Randomized, Double-Blind, Placebo-Controlled Trial. J Clin Neurol. 2022 Jul;18(4):478-480. doi: 10.3988/jcn.2022.18.4.478.
- Oketch-Rabah HA, Madden EF, Roe AL, Betz JM. United States Pharmacopeia (USP) Safety Review of Gamma-Aminobutyric Acid (GABA). Nutrients. 2021 Aug 10;13(8):2742. doi: 10.3390/nu13082742.
- Minuk GY. Gamma-aminobutyric acid and the liver. Dig Dis. 1993;11(1):45-54. doi: 10.1159/000171400.
- Hata T, Rehman F, Hori T, Nguyen JH. GABA, γ-Aminobutyric Acid, Protects Against Severe Liver Injury. J Surg Res. 2019 Apr;236:172-183. doi: 10.1016/j.jss.2018.11.047.
