If you search for over the counter remedies for insomnia or anxiety, you might discover at least one with GABA listed as an ingredient.
When I first took a sleep aid containing GABA, it was mixed with seven other ingredients. The sleep aid seemed to work, but there was no way to know if it was the GABA, another ingredient or even the placebo effect that did the trick.
So I decided to do see what research into GABA exists, and how strong the evidence is that it works as a sleep aid when taken as a supplement.
The bottom line is that scientists are still unsure how effective it is in supplement form. Some studies point to it helping with sleep, while others show only a marginal difference at best.
Let’s take a closer look at what I unearthed in my attempt to find out why it’s being added to more and more sleep aids.
What is GABA?
GABA (Gamma-Aminobutyric Acid) is a neurotransmitter produced naturally in the body, and it sends messages between the brain and the nervous system.
As the main ‘inhibitory neurotransmitter’ in the brain, its principal role is to reduce the activity of nerve cells in the nervous system.
By reducing the excitability of those nerve cells, GABA has a calming effect on the brain and body. So it’s thought to help reduce anxiety, stress, and promotes sleep. However, that effect happens in its natural form when it’s produced by your body – not bought online.
Conditions associated with GABA
Scientists are still working to fully understand the role of GABA. However, it’s clear that it’s an important neurotransmitter, and scientists say it’s associated with several aspects of both physical and mental health, such as:
- Anxiety and stress
- Premenstrual syndrome
- Human growth hormone levels
Lower GABA levels in people with primary insomnia
How is GABA related to your sleep exactly? Research into the GABA levels people with insomnia naturally have in their brain might provide some clues.
In 2004, researchers at the Harvard Medical School scanned the brains of 16 non-medicated people to measure their GABA levels.
They found those with primary insomnia had nearly 30% lower GABA levels in their brain. They also found lower levels were associated with waking sooner after first falling asleep.
Medications that work by increasing GABA activity
Researchers point out that there is a known connection between GABA receptors and sleep:
It is well established that activation of GABA(A) receptors favors sleep
And on that principle, several medications for anxiety and insomnia work by increasing GABA activity in the brain, including:
- Benzodiazepines (e.g. diazepam, temazepam, and lorazepam)
So if well-established sleeping pills work by targeting GABA in the brain, what else might do the same?
Can your body use the GABA in supplements?
Some scientists argue that GABA in supplement form just doesn’t work as a sleep aid. The reason being that several animal studies have shown that GABA taken orally can’t cross the blood-brain barrier.
The blood-brain barrier serves a critical role, preventing harmful substances from reaching the brain. It’s like your brain’s biological firewall.
However, researchers in 2015 challenged this long-held view in their paper on GABA supplementation, saying:
It has long been thought that GABA is unable to cross the blood–brain barrier (BBB), but the studies that have assessed this issue are often contradictory and range widely in their employed methods. There is some evidence in favor of a calming effect of GABA food supplements, but most of this evidence was reported by researchers with a potential conflict of interest. We conclude that the mechanism of action of GABA food supplements is far from clear, and that further work is needed to establish the behavioral effects of GABA.
Can GABA cross the blood-brain barrier?
The team of researchers also pointed out that some studies, such as this one in 2002, have found that GABA can cross the barrier in small quantities.
Other studies have shown that GABA supplements can help with relaxation and anxiety. For example, in 2006, researchers showed GABA supplements helped people with a fear of heights experience less anxiety when crossing a bridge.
So why do some studies show it can, while others that it can’t? Perhaps a few reasons:
- Only rats and dogs were tested for changes in GABA levels in most of the earlier studies – not humans.
- Not all research studies used the same GABA compounds.
- Studies used different methods of administration (oral and injection).
Making the barrier more permeable
Could it be that even if the blood-brain barrier is resistant to ingested GABA, it can be made more permeable?
The animal study in 2002 found that by giving rats both GABA and L-Arginine, the amount of GABA in the brain increased by four times more than just GABA alone.
The researchers suggested that the L-Arginine increases nitric oxide levels in the brain. And that makes the barrier more open to GABA.
Another study in 2001 found evidence that a GABA transporter might exist in the brain, which can help it cross the blood-brain barrier.
And more recently in 2019, researchers in Korea showed an improvement in the sleep of mice when they gave them a combination of GABA and L-theanine. They found that the time it took to fall asleep and the total sleep duration both improved, and the effect was better than if either supplement was taken alone.
So there does appear to be hope for the manufacturers of GABA supplements.
GABA in food form helps people fall asleep faster
In 2015, researchers from Pharma Foods International Co. Ltd. tested the effects of GABA on sleep. The GABA they used was produced by natural fermentation of a strain of lactic acid bacteria.
Using an EEG to monitor sleep, they found it shortened the time it took the participants to fall asleep by 5.3 minutes on average.
It should be noted there were a small number of participants in the study, but the results are still encouraging.
They also note that it would be safe to take it daily, as it’s a well-known food. And that’s good news for lovers of fermented vegetables, popular in some Asian countries, such as Kimchi.
Supplements or food form?
The above study raises an interesting question. Would it be better to try to increase GABA activity with supplements or normal food?
Increasing levels of GABA by eating food is arguably the safer option – assuming it’s possible and effective. It’s an area of research some scientists are actively exploring, with promising results.
Marina Diana and colleagues in Spain published a review of GABA-enriched foods in 2014. Like the study above, they focused on fermented food products, saying:
Lactic acid bacteria (LAB) are the main GABA-producers and therefore there are a wide range of GABA-enriched fermented food products, in which GABA is natural, safe and eco-friendly.
And in another study, they also looked at the GABA levels in Spanish artisan cheeses. Again, there were positive findings:
Ten Lactobacillus strains isolated from artisan Spanish cheeses showed high capacity of gamma-aminobutyric acid production.
On a personal level, I’ve taken a lot of interest in the human microbiome recently – it’s a developing area of science which is fascinating once you start reading about the connections scientists are finding between our brain and our ‘second brain’, i.e. the gut. And it doesn’t surprise me that our gut might have a role to play in how well we sleep. Fermented food to the rescue once again!
A recent review of GABA supplements highlights problems with previous studies
Researchers sometimes decide to scrutinize large numbers of previous research studies to see just how strong the evidence is. This kind of systematic review can be very useful, as they often highlight problems with some studies done in the past.
In 2020, a team in the United Kingdom took a close look at studies in which GABA had been tested on stress and sleep in humans. They left out poorer quality studies and only included those that had placebo-controlled human trials.
Although they found some evidence that GABA might help reduce how long it takes to fall asleep, they didn’t find strong evidence that it helps with overall sleeep quality or total sleep time.
They summarized their analysis this way:
Although more studies are needed before any inferences can be made about the efficacy of oral GABA consumption on stress and sleep, results show that there is limited evidence for stress and very limited evidence for sleep benefits of oral GABA intake.
This doesn’t look so good then if you were planning on buying some GABA supplements to help you sleep! Having said that, I do think it’s important to keep in mind that this is still an area where more research is needed.
But it does highlight that where GABA is concerned, we’re not taking about a sleep aid you can easily buy that will definitely have an impact on your sleep. So if you do decide to try it, perhaps lower your expectations a little.
Side effects and safety of GABA supplements
There isn’t enough research into the possible side effects of taking GABA in supplements.
There don’t appear to be serious safety fears occurring in research studies. However, because it’s still a developing area, most medical sources advise the following:
- Pregnant or breastfeeding women should avoid taking it.
- If already taking medication for anxiety, depression or insomnia, speak to your doctor first.
- If you experience any possible side effects, for example, skin tingling, flushing, breathing difficulties or changes in mood, speak to a doctor.
Have you taken GABA supplements?
If you’ve tried GABA supplements, I’d love to hear from you. What health condition did you take them for, and did you notice any effect?