Table of ContentsView AllTable of ContentsWhat Is GABA?FunctionUsesSide EffectsPrecautionsDosageToxicityInteractionsSimilar SupplementsSources & What to Look For
Table of ContentsView All
View All
Table of Contents
What Is GABA?
Function
Uses
Side Effects
Precautions
Dosage
Toxicity
Interactions
Similar Supplements
Sources & What to Look For
GABA supplements are believed to help reduce anxiety, improve sleep, and support relaxation. Many people think that GABA can assist in managing stress and mood, as it plays a role in calming the nervous system. It is found in foods like tea and cruciferous vegetables but is often taken in higher amounts through supplements.
Research on GABA is still developing, and while some studies suggest it may raise levels in the blood, it’s unclear if it effectively reaches the brain. Though there are reports of positive effects on stress and sleep, more thorough studies are needed to confirm these benefits and understand how GABA functions in the body.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
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Function of GABA
As a neurotransmitter, GABA sends messages throughout the central nervous system. Because it is an inhibitory neurotransmitter, GABA blocks or inhibits certain nerve transmission, so messages aren’t sent on to other neurons.
This slowdown in message transition may help produce a calming effect and may play a role in controlling anxiety, stress, and fear.
Effects of GABA Supplements
Like many supplements, people may use GABA for various reasons. However, there are several clinical trials assessing GABA for the following potential uses.
Sleep Quality
Stress
A study of 30 people suggested GABA-enriched oolong tea was linked with lower short-term stress scores than regular oolong tea.Larger, well-designed studies are needed to confirm these results.
Blood Pressure
There are numerous small studies about GABA’s effects on lowering blood pressure. However, the results are mixed. This may have something to do with each study’s different GABA dosages and dosage forms—like soy sauce, fermented milk, and specific GABA tablets.
Supplement FactsActive ingredient(s):Gamma-aminobutyric acidAlternate name(s): 4-aminobutanoic acid, fermented rice germ extract containing GABA (RFE-GABA), GABA, γ-aminobutyric acidLegal status: Legal OTC supplement in most U.S. statesSuggested dose: Varies based on conditionSafety considerations: Research on the use in pregnancy and breastfeeding and use in children in progress;may interact with some prescription medications
Supplement Facts
Active ingredient(s):Gamma-aminobutyric acidAlternate name(s): 4-aminobutanoic acid, fermented rice germ extract containing GABA (RFE-GABA), GABA, γ-aminobutyric acidLegal status: Legal OTC supplement in most U.S. statesSuggested dose: Varies based on conditionSafety considerations: Research on the use in pregnancy and breastfeeding and use in children in progress;may interact with some prescription medications
What Are the Side Effects of GABA Supplements?
As with many medications and supplements, side effects are possible with GABA.
Common Side Effects
Common side effects of GABA may include:
While common, these side effects tend to go away within a few minutes.
Severe Side Effects
Presently, there are no studies that specifically assess GABA’s safety. But several clinical trials suggest that GABA isn’t linked to severe side effects, except forlow blood pressure. You may feel faint with low blood pressure.
Severe allergic reaction is another serious side effect possible with any medication or supplement. If you’re having a severe allergic reaction to GABA, get medical help immediately. Symptoms may include breathing difficulties, itchiness, and rash.
Call 911 if your symptoms feel life-threatening.
Your healthcare practitioner may advise against using GABA if any of the following applies to you:
Dosage: How Much GABA Should I Take?
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.
Because there is limited information about GABA supplements, there are no guidelines on the appropriate dosage for any condition.
To safely take natural medications like GABA, follow the directions on the label and inform your healthcare providers and pharmacists about any medication changes.This includes OTC herbal, natural medicines, and supplements. They can help prevent possible interactions and side effects. They can also ensure that you’re giving GABA a fair trial at appropriate doses.
What Happens if I Take Too Much GABA?
There is limited information about GABA toxicity and overdoses. Data has shown no serious adverse events associated with GABA at intakes up to 18 grams per day for four days and in longer studies at intakes of 120 milligrams per day for 12 weeks.
However, high daily doses of GABA (5 to 10 grams) may result in a burning sensation in your throat and low blood pressure. The upper recommended intake is typically 3 grams per day—with no more than 750 milligrams per dose.
Talk with your healthcare provider before taking GABA—especially if you’re planning to take at least 300 milligrams per day for more than four weeks.
Use caution when taking GABA with the following:
It is essential to carefully read a supplement’s ingredients list and nutrition facts panel to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss potential interactions with foods, other supplements, and medications.
GABA is an amino acid.Other similar amino acids also available as supplements include:
Like GABA, 5-HTP and L-tryptophan have been studied as a potential sleep aid. However, current research doesn’t support 5-HTP and L-tryptophan to help with sleep.
5-HTP and L-tryptophan are also purported to improve mood because they convert intoserotonin, a naturally occurring brain chemical that affects mood.However, there is little data to support this use.Theoretically taking these supplements could also cause a condition calledserotonin syndromein whichhigh blood pressureis a symptom.
Sources of GABA and What to Look For
While GABA is available as an OTC supplement, there are other sources of GABA.
Food Sources of GABA
You can get natural sources of GABA through your diet. Examples of GABA-containing foods include:
Drastic dietary changes may interact with your medications or affect your medical conditions. For this reason, talk with your healthcare provider first. They will help you safely make these changes.
GABA Supplements
GABA is available in many dosage forms, including capsules and tablets. If you have difficulty swallowing pills, GABA is available in the following dosage forms:
GABA also has vegan or vegetarian products.
Which supplement you choose primarily comes down to your preference and what you hope to get in terms of effects. Each product may work differently depending on the form, so following the directions is essential.
Other Ways to Increase GABAMind-body practices might help boost your brain’s GABA levels. One study found practicing yoga and breathing exercises may lead to higher GABA levels.However, further studies are needed to confirm these results.
Other Ways to Increase GABA
Mind-body practices might help boost your brain’s GABA levels. One study found practicing yoga and breathing exercises may lead to higher GABA levels.However, further studies are needed to confirm these results.
Summary
GABA is an amino acid and neurotransmitter that may help improve your mood and sleep. Several studies show that increased GABA levels in the brain can help decrease anxiety, stress, and depression.
However, very little GABA may cross the blood-brain barrier when taken in oral supplement form. More research is needed to assess GABA’s effectiveness and safety. Before taking GABA, talk with your pharmacist or healthcare provider to help you safely achieve your health goals.
18 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Hepsomali P, Groeger JA, Nishihira J, et al.Effects of oral gamma-aminobutyric acid (GABA) administration on stress and sleep in humans: a systematic review.Front Neurosci. 2020 Sep;14(1):923. doi:10.3389/fnins.2020.00923Wan Y, Wang Q, Prud’homme GJ.GABAergic system in the endocrine pancreas: a new target for diabetes treatment. Diabetes Metab Syndr Obes. 2015 Feb 3;8:79-87. doi: 10.2147/DMSO.S50642Cold Spring Harbor Laboratory.GABA Neurotransmitter.Boonstra E, de Kleijn R, Colzato LS, Alkemade A, Forstmann BU, Nieuwenhuis S.Neurotransmitters as food supplements: the effects of GABA on brain and behavior.Front Psychol. 2015;6. doi:10.3389/fpsyg.2015.01520Byun JI, Shin YY, Chung SE, et al.Safety and efficacy of gamma-aminobutyric acid from fermented rice germ in patients with insomnia symptoms: a randomized, double-blind trial.Journal of Clinical Neurology. 2018;14(3):291-295. doi: 10.3988%2Fjcn.2018.14.3.291Hinton T, Jelinek HF, Viengkhou V, et al.Effect of GABA-fortified oolong tea on reducing stress in a university student cohort.Frontiers in Nutrition. 2019;6:27. doi: 10.3389%2Ffnut.2019.00027Oketch-Rabah HA, Madden EF, Roe AL, et al.United States Pharmacopeia (USP) safety review ofgamma-aminobutyric acid (GABA).Nutrients. 2021;13(8):2742. doi: 10.3390%2Fnu13082742.ClinicalTrials.gov.Effect of GABA on ADHD and seizures in children with epilepsy.Reid SNS, Ryu JK, Kim Y, et al.The effects of fermentedLaminaria japonicaon short-term working memory and physical fitness in the elderly.Evidence-Based Complementary and Alternative Medicine. 2018;2018:8109621. doi: 10.1155%2F2018%2F8109621MedlinePlus.A guide to herbal remedies.ScienceDirect.5-hydroxytryptophan.MedlinePlus.L-tryptophan.MedlinePlus.5-HTP.Briguglio M, Dell’-Osso B, Panzica G.Dietary neurotransmitters: A narrative review on current knowledge.Nutrients. 2018:10(5):591. doi: 10.3390%2Fnu10050591de Bie TH, Balvers MGJ, de Vos RCH, et al.The influence of a tomato food matrix on the bioavailability and plasma kinetics of oral gamma-aminobutyric acid (GABA) and its precursor glutamate in healthy men. Food Funct. 2022 Aug 15;13(16):8399-8410. doi: 10.1039/d2fo01358dKumar P, Kraal AZ, Prawdzik AM, Ringold AE, Ellingrod V.Dietary Glutamic Acid, Obesity, and Depressive Symptoms in Patients With Schizophrenia.Front Psychiatry. 2021;11:620097. Published 2021 Jan 21. doi:10.3389/fpsyt.2020.620097National Institutes of Health Office of Dietary Supplements.Dietary supplement label database.Streeter CC, Gerbarg PL, Brown RP, et al.Thalamic gamma aminobutyric acid level changes in major depressive disorder after a 12-week iyengar yoga and coherent breathing intervention.The Journal of Alternative and Complementary Medicine. 2020;26(3):190-197. doi:10.1089/acm.2019.0234
18 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Hepsomali P, Groeger JA, Nishihira J, et al.Effects of oral gamma-aminobutyric acid (GABA) administration on stress and sleep in humans: a systematic review.Front Neurosci. 2020 Sep;14(1):923. doi:10.3389/fnins.2020.00923Wan Y, Wang Q, Prud’homme GJ.GABAergic system in the endocrine pancreas: a new target for diabetes treatment. Diabetes Metab Syndr Obes. 2015 Feb 3;8:79-87. doi: 10.2147/DMSO.S50642Cold Spring Harbor Laboratory.GABA Neurotransmitter.Boonstra E, de Kleijn R, Colzato LS, Alkemade A, Forstmann BU, Nieuwenhuis S.Neurotransmitters as food supplements: the effects of GABA on brain and behavior.Front Psychol. 2015;6. doi:10.3389/fpsyg.2015.01520Byun JI, Shin YY, Chung SE, et al.Safety and efficacy of gamma-aminobutyric acid from fermented rice germ in patients with insomnia symptoms: a randomized, double-blind trial.Journal of Clinical Neurology. 2018;14(3):291-295. doi: 10.3988%2Fjcn.2018.14.3.291Hinton T, Jelinek HF, Viengkhou V, et al.Effect of GABA-fortified oolong tea on reducing stress in a university student cohort.Frontiers in Nutrition. 2019;6:27. doi: 10.3389%2Ffnut.2019.00027Oketch-Rabah HA, Madden EF, Roe AL, et al.United States Pharmacopeia (USP) safety review ofgamma-aminobutyric acid (GABA).Nutrients. 2021;13(8):2742. doi: 10.3390%2Fnu13082742.ClinicalTrials.gov.Effect of GABA on ADHD and seizures in children with epilepsy.Reid SNS, Ryu JK, Kim Y, et al.The effects of fermentedLaminaria japonicaon short-term working memory and physical fitness in the elderly.Evidence-Based Complementary and Alternative Medicine. 2018;2018:8109621. doi: 10.1155%2F2018%2F8109621MedlinePlus.A guide to herbal remedies.ScienceDirect.5-hydroxytryptophan.MedlinePlus.L-tryptophan.MedlinePlus.5-HTP.Briguglio M, Dell’-Osso B, Panzica G.Dietary neurotransmitters: A narrative review on current knowledge.Nutrients. 2018:10(5):591. doi: 10.3390%2Fnu10050591de Bie TH, Balvers MGJ, de Vos RCH, et al.The influence of a tomato food matrix on the bioavailability and plasma kinetics of oral gamma-aminobutyric acid (GABA) and its precursor glutamate in healthy men. Food Funct. 2022 Aug 15;13(16):8399-8410. doi: 10.1039/d2fo01358dKumar P, Kraal AZ, Prawdzik AM, Ringold AE, Ellingrod V.Dietary Glutamic Acid, Obesity, and Depressive Symptoms in Patients With Schizophrenia.Front Psychiatry. 2021;11:620097. Published 2021 Jan 21. doi:10.3389/fpsyt.2020.620097National Institutes of Health Office of Dietary Supplements.Dietary supplement label database.Streeter CC, Gerbarg PL, Brown RP, et al.Thalamic gamma aminobutyric acid level changes in major depressive disorder after a 12-week iyengar yoga and coherent breathing intervention.The Journal of Alternative and Complementary Medicine. 2020;26(3):190-197. doi:10.1089/acm.2019.0234
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Hepsomali P, Groeger JA, Nishihira J, et al.Effects of oral gamma-aminobutyric acid (GABA) administration on stress and sleep in humans: a systematic review.Front Neurosci. 2020 Sep;14(1):923. doi:10.3389/fnins.2020.00923Wan Y, Wang Q, Prud’homme GJ.GABAergic system in the endocrine pancreas: a new target for diabetes treatment. Diabetes Metab Syndr Obes. 2015 Feb 3;8:79-87. doi: 10.2147/DMSO.S50642Cold Spring Harbor Laboratory.GABA Neurotransmitter.Boonstra E, de Kleijn R, Colzato LS, Alkemade A, Forstmann BU, Nieuwenhuis S.Neurotransmitters as food supplements: the effects of GABA on brain and behavior.Front Psychol. 2015;6. doi:10.3389/fpsyg.2015.01520Byun JI, Shin YY, Chung SE, et al.Safety and efficacy of gamma-aminobutyric acid from fermented rice germ in patients with insomnia symptoms: a randomized, double-blind trial.Journal of Clinical Neurology. 2018;14(3):291-295. doi: 10.3988%2Fjcn.2018.14.3.291Hinton T, Jelinek HF, Viengkhou V, et al.Effect of GABA-fortified oolong tea on reducing stress in a university student cohort.Frontiers in Nutrition. 2019;6:27. doi: 10.3389%2Ffnut.2019.00027Oketch-Rabah HA, Madden EF, Roe AL, et al.United States Pharmacopeia (USP) safety review ofgamma-aminobutyric acid (GABA).Nutrients. 2021;13(8):2742. doi: 10.3390%2Fnu13082742.ClinicalTrials.gov.Effect of GABA on ADHD and seizures in children with epilepsy.Reid SNS, Ryu JK, Kim Y, et al.The effects of fermentedLaminaria japonicaon short-term working memory and physical fitness in the elderly.Evidence-Based Complementary and Alternative Medicine. 2018;2018:8109621. doi: 10.1155%2F2018%2F8109621MedlinePlus.A guide to herbal remedies.ScienceDirect.5-hydroxytryptophan.MedlinePlus.L-tryptophan.MedlinePlus.5-HTP.Briguglio M, Dell’-Osso B, Panzica G.Dietary neurotransmitters: A narrative review on current knowledge.Nutrients. 2018:10(5):591. doi: 10.3390%2Fnu10050591de Bie TH, Balvers MGJ, de Vos RCH, et al.The influence of a tomato food matrix on the bioavailability and plasma kinetics of oral gamma-aminobutyric acid (GABA) and its precursor glutamate in healthy men. Food Funct. 2022 Aug 15;13(16):8399-8410. doi: 10.1039/d2fo01358dKumar P, Kraal AZ, Prawdzik AM, Ringold AE, Ellingrod V.Dietary Glutamic Acid, Obesity, and Depressive Symptoms in Patients With Schizophrenia.Front Psychiatry. 2021;11:620097. Published 2021 Jan 21. doi:10.3389/fpsyt.2020.620097National Institutes of Health Office of Dietary Supplements.Dietary supplement label database.Streeter CC, Gerbarg PL, Brown RP, et al.Thalamic gamma aminobutyric acid level changes in major depressive disorder after a 12-week iyengar yoga and coherent breathing intervention.The Journal of Alternative and Complementary Medicine. 2020;26(3):190-197. doi:10.1089/acm.2019.0234
Hepsomali P, Groeger JA, Nishihira J, et al.Effects of oral gamma-aminobutyric acid (GABA) administration on stress and sleep in humans: a systematic review.Front Neurosci. 2020 Sep;14(1):923. doi:10.3389/fnins.2020.00923
Wan Y, Wang Q, Prud’homme GJ.GABAergic system in the endocrine pancreas: a new target for diabetes treatment. Diabetes Metab Syndr Obes. 2015 Feb 3;8:79-87. doi: 10.2147/DMSO.S50642
Cold Spring Harbor Laboratory.GABA Neurotransmitter.
Boonstra E, de Kleijn R, Colzato LS, Alkemade A, Forstmann BU, Nieuwenhuis S.Neurotransmitters as food supplements: the effects of GABA on brain and behavior.Front Psychol. 2015;6. doi:10.3389/fpsyg.2015.01520
Byun JI, Shin YY, Chung SE, et al.Safety and efficacy of gamma-aminobutyric acid from fermented rice germ in patients with insomnia symptoms: a randomized, double-blind trial.Journal of Clinical Neurology. 2018;14(3):291-295. doi: 10.3988%2Fjcn.2018.14.3.291
Hinton T, Jelinek HF, Viengkhou V, et al.Effect of GABA-fortified oolong tea on reducing stress in a university student cohort.Frontiers in Nutrition. 2019;6:27. doi: 10.3389%2Ffnut.2019.00027
Oketch-Rabah HA, Madden EF, Roe AL, et al.United States Pharmacopeia (USP) safety review ofgamma-aminobutyric acid (GABA).Nutrients. 2021;13(8):2742. doi: 10.3390%2Fnu13082742.
ClinicalTrials.gov.Effect of GABA on ADHD and seizures in children with epilepsy.
Reid SNS, Ryu JK, Kim Y, et al.The effects of fermentedLaminaria japonicaon short-term working memory and physical fitness in the elderly.Evidence-Based Complementary and Alternative Medicine. 2018;2018:8109621. doi: 10.1155%2F2018%2F8109621
MedlinePlus.A guide to herbal remedies.
ScienceDirect.5-hydroxytryptophan.
MedlinePlus.L-tryptophan.
MedlinePlus.5-HTP.
Briguglio M, Dell’-Osso B, Panzica G.Dietary neurotransmitters: A narrative review on current knowledge.Nutrients. 2018:10(5):591. doi: 10.3390%2Fnu10050591
de Bie TH, Balvers MGJ, de Vos RCH, et al.The influence of a tomato food matrix on the bioavailability and plasma kinetics of oral gamma-aminobutyric acid (GABA) and its precursor glutamate in healthy men. Food Funct. 2022 Aug 15;13(16):8399-8410. doi: 10.1039/d2fo01358d
Kumar P, Kraal AZ, Prawdzik AM, Ringold AE, Ellingrod V.Dietary Glutamic Acid, Obesity, and Depressive Symptoms in Patients With Schizophrenia.Front Psychiatry. 2021;11:620097. Published 2021 Jan 21. doi:10.3389/fpsyt.2020.620097
National Institutes of Health Office of Dietary Supplements.Dietary supplement label database.
Streeter CC, Gerbarg PL, Brown RP, et al.Thalamic gamma aminobutyric acid level changes in major depressive disorder after a 12-week iyengar yoga and coherent breathing intervention.The Journal of Alternative and Complementary Medicine. 2020;26(3):190-197. doi:10.1089/acm.2019.0234
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