Gamma-Aminobutyric Acid (GABA)

What is gamma-aminobutyric acid (GABA)?

Gamma-aminobutyric acid (GABA) is a neurotransmitter, a chemical messenger in your brain. It slows down your brain by blocking specific signals in your central nervous system (your brain and spinal cord).

GABA is known for producing a calming effect. It’s thought to play a major role in controlling nerve cell hyperactivity associated with anxiety, stress and fear.

Scientists also call GABA a non-protein amino acid neurotransmitter.

How does gamma-aminobutyric acid (GABA) work?

GABA is the most common inhibitory neurotransmitter in your central nervous system. Inhibitory neurotransmitters prevent or block chemical messages and decrease the stimulation of nerve cells in your brain.

Neurotransmitters all generally work in the same way. They are chemical messengers that carry messages from one nerve cell in your brain to the next. Between each nerve cell is a tiny amount of fluid-filled space called a synapse. Neurotransmitters must carry their message across this synapse and then land on and bind to specific receptors on the next nerve cell (like a key that can only fit and work in its partner lock).

There are two types of GABA receptors on nerve cells — GABA-A and GABA-B. Although they work in different ways, when GABA binds to these receptors the result is that they decrease the responsiveness of the nerve cell. This means that as an inhibitory neurotransmitter, GABA lessens the ability of a nerve cell to receive, create or send chemical messages to other nerve cells.

What are the health benefits of GABA?

By slowing certain brain functions, GABA is thought to be able to:

• Reduce stress.
• Relieve anxiety.
• Improve sleep.

What is GABA’s relationship to glutamate?

GABA and glutamate act like an “on” and “off” switch. They work in opposite ways. GABA is the main inhibitory neurotransmitter in your brain, stopping the chemical messages from passing from nerve cell to nerve cell. Glutamate, on the other hand, is the main excitatory neurotransmitter in your brain, permitting the chemical messages to be carried from nerve cell to nerve cell.

To have a properly functioning brain, a delicate balance must be maintained between the inhibitory effects of GABA and the excitatory effects of glutamate. GABA also works together with another neurotransmitter, serotonin. In fact, many neurotransmitters work together and against each other and must maintain a certain relationship to achieve a properly functioning body and brain.

GABA is actually made from glutamate following a reaction with the enzyme glutamic acid decarboxylase.

What medical conditions are associated with changes in the level of GABA?

Certain neurologic and mental health conditions are thought to be related to times when GABA messaging activity (“signaling”) isn’t in balance and working as it should. Decreased GABA activity may contribute to:

• Anxiety and mood disorders.
• Schizophrenia.
• Autism spectrum disorder.
• Depression.
• Epilepsy, seizures.

Other medical conditions associated with GABA imbalance include:

• Pyridoxine deficiency. This is a rare disease in which a vitamin that’s needed to make GABA isn’t available. It usually causes frequent seizures during infancy. The seizures aren’t successfully treated with anticonvulsant medications, but do respond to vitamin supplementation.
• Hepatic encephalopathy.
• Huntington disease.
• Dystonia and spasticity.
• Hypersomnia (excess daytime sleepiness or excessive time spent sleeping).

Does increasing GABA levels provide any health benefits?

Researchers are still studying the effects of increased levels of GABA. Although the evidence isn’t clear, GABA is being looked at to help treat or prevent health conditions including:

• High blood pressure.
• Insomnia.
• Diabetes.

What medications target GABA?

Many medications have been developed that act on the GABA receptors. These include:

• Benzodiazepines. This class of drugs, which includes diazepam (Valium®) and alprazolam (Xanax®), acts on the GABA-A receptor. Benzodiazepines are used in surgical anesthesia, treatment of epilepsy, REM-sleep disorders, alcohol withdrawal, anxiety, essential tremor and muscle spasticity.
• Barbiturates. These are sedative drugs.
• Vigabatrin (Sabril®). This is a drug used to treat seizures and spasms in infants.
• Flumazenil (Romazicon®). This drug is used to treat benzodiazepine overdose. It’s also used to improve the mental status of people with hepatic encephalopathy.
• Valproic acid. This medication is a mood stabilizer and an anti-seizure medication.
• Zolpidem (Ambien®, Edluar®). This is a sedative-hypnotic. It’s used to treat insomnia.
• Propofol (Diprivan®). This drug is a sedative used in general anesthesia.
• Baclofen (Lioresal®, Gablofen®). This drug is a muscle relaxant.

Is a GABA supplement available?

GABA is available as a dietary supplement. However, much of it might not be able to get into your brain. (Technically, this is called “crossing the blood-brain barrier.” The barrier is a unique membrane that only allows certain molecules to pass through it to and from your brain). So, it’s not known what effects — if any — taking dietary GABA supplements may have on your brain. So far, there isn’t any strong scientific evidence to support the use of a GABA supplement for treating medical conditions. More studies, in larger numbers of people, are needed.

Is GABA present in food?

GABA is present in some fermented foods, including kimchi, miso and tempeh. It’s also found in green, black and oolong tea. Other foods that contain GABA or boost its production in your body include brown rice, soy and adzuki beans, chestnuts, mushrooms, tomatoes, spinach, broccoli, cabbage, cauliflower, Brussels sprouts, sprouted grains and sweet potatoes.

Like supplements, it’s not fully clear if eating GABA-containing foods allows GABA to reach your brain. More studies, with large numbers of people, need to be conducted.

A note from Cleveland Clinic

Gamma-aminobutyric acid (GABA) is the most common inhibitory neurotransmitter in your central nervous system. GABA lessens the ability of a nerve cell to receive, create or send chemical messages to other nerve cells. GABA is known for producing a calming effect. It’s thought to play a major role in controlling anxiety, stress and fear. Decreased GABA levels are associated with several neurological and mental health conditions, as well as other medical conditions. Increasing GABA levels may help treat high blood pressure, diabetes and insomnia. Because of the abundance of GABA in your brain, the GABA receptor is a major target of drug development by pharmaceutical manufacturers. The effectiveness of GABA supplements and GABA-containing foods to prevent and treat medical conditions needs to be studied in a larger number of people. Before purchasing GABA supplements or eating certain GABA-containing foods, talk to your healthcare provider about the best approach to treat your health condition.