How to test your blood-brain barrier with a simple home test
using GABA supplements

Is a leaky blood-brain barrier causing a mental Health Problems?
The blood-brain barrier is a specialist membrane that separates and protects the brain from harmful molecules, viruses and bacteria in the blood.
A healthy blood-brain barrier will also not let GABA pass through so the GABA from supplements should not be able to reach the brain and produce any therapeutic effects. A leaky blood-brain barrier, however, will let GABA through and produce immediate effects on our brain that we can feel; we can use this effect as a simple home test of the health of our blood-brain barrier.
Elsewhere I discuss why you shouldn’t use GABA supplements to boost GABA levels as a treatment for anxiety, but here I’m going to explain how you can use GABA supplements to see if your BBB is too leaky.

The blood-brain barrier BBB is made up of a layer of tightly bound cells surrounding the blood vessels within the brain, these cells are very tightly bound together with only tiny gaps (called tight junctions) between them, the tight junctions are so small that even tiny nano-sized particles like viruses and large molecules like GABA cannot pass through. When this membrane is damaged or inflamed however the gaps between the cells expand (called loose junctions) allowing toxic molecules and pathogens to enter the brain. This triggers the brains inflammatory immune responses, and we now know inflammation in the brain is a fundamental root cause of mental health problems, inflammation in the brain can also cause ‘brain-fog’, slow thinking and pool mental stamina.
Unlike other neurotransmitters GABA is actually just a simple pure amino acid, amino acids are the building blocks of protein so every time we eat protein we are ingesting GABA. It makes perfect sense that the BBB has been designed to prevent GABA from the food we eat from entering the brain. If the blood-brain barrier allowed GABA through it would mean every time we ate protein-containing foods the GABA released from our digestive system could travel through the blood and enter the brain whereupon it would cause a surge in GABA levels and throw out the brains neurotransmitter balance.
Not only will a leaky blood-brain barrier allow GABA from our diet and supplements to enter the brain but it will also allow half-digested food molecules, gluten, toxic substances, viruses and bacteria through. As I discussed elsewhere unwanted toxic substances entering the brain is triggers inflammation in the brain which can damage delicate structures involved in maintaining mental health and cognitive abilities. If you fail this GABA challenge test you should work on repairing your BBB.
The protective nature of the BBB does not just inhibit GABA supplements from being effective, it also presents a big challenge in delivering drugs and other remedies to the brain.

Performing the Leaky Brain GABA Challenge Test:

To be safe you should perform a pre-test the day before performing the main challenge test by taking a low dose of just 500 mg of GABA on an empty stomach, it’s possible even 500 mg could produce a sedating effect so use your common sense and only do this when you’re not going to do anything demanding like driving.
In the pre-test, you are checking to see that you don’t have any strong reactions to GABA. You are looking for changes in your pulse rate and breathing; if your pulse speed up or your breathing feels laboured don’t take GABA again, unfortunately, this means you shouldn’t perform the full test with a higher dosage. Don’t let the suggestion for this pre-test put you off taking GABA, I’m just being ultra-cautious because I’ve heard of these effects anecdotally but in my practice, I’ve never known anyone experience significant changes in their pulse rate or difficulty breathing from taking GABA.

How to Perform the GABA BBB Challenge Test

At a time when it would be okay if you took a nap for several hours i.e. in the evening or perhaps at the weekend take 1000 mg of GABA on an empty stomach. By an empty stomach I mean you’ve had nothing to eat 2 ½ hours and you don’t eat anything after taking the GABA for at least 30 minutes.
If the GABA gets into your brain it will produce the following effects:-
  • A noticeable calm feeling,
  • A tranquilizing effect,
  • Feeling very relaxed,
  • A significant reduction in the feelings of anxiety,
  • Feeling very drowsy and sleepy,
Paradoxical effects:-
If you experience the above effects, then you have a leaky blood-brain barrier and you need to heal it as part of your mental health recovery program. See healing a leaky brain (UNDER CONSTRUCTION). If you have anxiety or insomnia and find GABA has useful therapeutic effects you may be tempted to continue using it as a supplement but you shouldn’t because doing so may cause your brain to lose sensitivity to GABA, see Why You Shouldn’t Take GABA Supplements
Sometimes GABA supplements will produce the opposite effect, instead of making you feel calm and relaxed it may make you feel agitated and tense. These paradoxical effects are quite common, they occur when your neurons synapses and receptor sites are in a very unhealthy condition, exhausted and near a state of collapse; when made to work harder with natural remedies they quickly become exhausted stop working. It’s like pushing a muscle to the point of exhaustion and collapse by making it work harder.
If you get no effects or you are not sure you could try the test again but next time with a much higher dose of 3000mg, if this does not have a clear effect on you it suggests your BBB is in good condition. 

Keep Repeating the GABA Challenge Test until your BBB is Healed

As you work on healing your leaky BBB once a month or so you repeat the leaky brain GABA challenge test to assess your progress. Once you can take GABA supplements without them having any effects your BBB should be in good condition.

You can use GABA to test how specific foods, diets and supplements affect the health of your BBB

You can also use this test as an experiment to see how a change in your diet, your supplement regime or a specific food affect the health of your BBB. For example I used to eat wheat just twice a week and even at this level it provoked sufficient inflammation and breakdown of my BBB that when I take GABA I would feel the effects, on the days after I ate wheat GABA supplements would send me to sleep.
I wanted to have a bread that I could eat so I started making my own with sourdough, spelt and rye flour, this bread is low-gluten but not gluten-free; furthermore, the sourdough bacteria particularly L plantarum protect against gluten sensitivity. To test the effect of this bread I ate a lot of it for two weeks and was delighted to discover that my BBB remained intact and I passed the GABA BBB challenge test :-) I’ll send you my recipe if you like.

The GABA BBB Challenge Test Is Not Validated by Science

The GABA BBB challenge test is not scientifically validated, it’s a rough home test that we use in alternative medicine; there’s actually very little scientific research into GABA and BBB. My clinical observation was that GABA supplements would work in people with high levels of inflammation and poor health but not in others, then I worked out that when I eat wheat GABA supplements would affect me but they wouldn’t affect me when I didn’t eat wheat, then Dr Kharrazian in the book Why Isn’t My Brain Working proposed using GABA supplements as a test of the integrity of the BBB. So I just want to be clear this is not a precise validated way of testing the health of your BBB, it is however a novel and I believe a useful rough and ready way to assess the health of your BBB and the progress of your treatment.
I specialise in treating and coaching people with mental health problems how to obtain better mental health with natural remedies and self-help techniques. If you would like me to look into your individual case and develop a tailor-made programme of natural remedies, dietary advice and brain training exercises I’m available for private consultations at my London clinic and online for people that live too far away.
I also run regular meditation classes in London and online.
Click on the
bookings tab to make an appointment.
I’m passionate about treating mental health and I’d be very happy to work with you.

Do Pharma GABA Supplements Cross the Blood-Brain Barrier Better Than Regular Supplements?

There’s a supplement called Pharma GABA that is produced by a fermentation process using lactobacillus hilgardii that is claimed to cross the blood-brain barrier better than other GABA supplements; unfortunately one of the authors involved in producing this scientific evidence had a financial conflict of interest. This just means the evidence is unreliable it doesn’t mean it’s false[i]. I have not bothered to conduct personal or clinical trials in my practice on this form of GABA because I fundamentally don’t believe causing surges in GABA in the brain is a healthy thing to do; as I said elsewhere the concern is that the brain may start desensitising itself to GABA to protect itself from the surges leading to you becoming more dependent on GABA supplementation because your brain is even less sensitive to it.

GABA and Human Growth Hormone A Fat Loss Technique

GABA supplements before bed have been shown in numerous studies to increases human growth hormone levels in the blood by up to five and a half fold within 90 minutes of ingestion[ii]. This impressive effect is stronger than any other natural remedies can achieve and rivals what can be achieved with pharmaceuticals. As long as your BBB is in good condition so that you are not flooding your brain with GABA you can combine high dose GABA supplementation with weight/strength training to turbocharge a weight-loss program.
The rate of muscle growth is influenced by growth hormone levels, which are at their highest while you sleep. By reducing your calorie intake and supplementing GABA before going to bed on the same days you do strength-training you can increase muscle growth and fat loss.
Just to be clear strength-training involves using weights heavy enough to push your muscles to the point of failure, resting for a minute or so and then pushing the muscles to the point of failure two or three more times.
In response to being overwhelmed to the point of failure muscles will try to grow bigger, and as they grow they burn lots of calories. The calories have to come from somewhere, and as long as you don’t add the extra calories to your diet the muscles will eat into your body fat to get the calories they need. The basic principle is say you wanted to loose 10 kilo’s (22 lbs.) of body fat you should you set out to grow 2 kilo’s (5 lbs.) of muscle.
To use this effect look up your recommended sedentary daily calorie needs and eat that amount or less. Take 3000−5000 mg of GABA immediately before bed on days you do an intensive weight/strength-training workout. 
Strength-training can injure you if you don’t know what you are doing, so get some tuition and you must build up to it slowly over months if you are a novice to build up the strength and density of your ligaments and tendons.
Caution: Obviously do not use GABA to boost hGH if you have failed the leaky brain GABA challenge test, if your BBB is in good condition using GABA is okay, GABA does not itself damage the BBB and is otherwise a very safe supplement. I don’t know if GABA supplements are safe during pregnancy or breastfeeding so don’t use them.

GABA Safety

GABA does not have any major side-effects and is generally considered very safe. According to one website I have read it’s possible for GABA to produce temporary changes in one's breathing (either too fast or too slow) and an increased heart rate, however, I have never observed this in my practice. Another suggested side-effect of GABA that I've only seen once is temporary and mild tingling sensations.
There are no known adverse interactions between GABA and other medications. Intuitively one might think that combining GABA with tranquilizers and anti-anxiety medications such as Valium or benzodiazepine may be too sedating; however, this has not been reported in the medical literature and I have had people perform the leaky brain GABA challenge test while taking tranquilisers and antianxiety medications at the same time.

Buying GABA

GABA is considered a prescription medicine in the UK, but available for sale in the US, use Now Foods GABA from
Related Articles:
GABA Deficient Anxiety
How Meditation Treats the Anxious Brain
Is an Overactive Default Mode Network Causing your Anxiety and Depression?
What's the Best Meditation for Depression Anxiety and Bipolar?
Meditation Classes for Bipolar Depression Anxiety
Benzo Withdrawal How to Speed up Recovery
Benzo Withdrawal Treatment with Natural Remedies
Are Natural Remedies Safe Benzo Diazepam Withdrawal?

[i] Front Psychol. 2015; 6: 1520. Published online 2015 Oct 6. doi: [10.3389/fpsyg.2015.01520] PMCID: PMC4594160 PMID: 26500584 Neurotransmitters as food supplements: the effects of GABA on brain and behaviour Evert Boonstra, et al
[ii] Med Sci Sports Exerc. 2008 Jan;40(1):104-10. Growth hormone isoform responses to GABA ingestion at rest and after exercise. Powers PMID: 18091016 DOI: 10.1249/mss.0b013e318158b518
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I also run regular meditation classes in London and online.
I’m passionate about treating mental health and I’d be very happy to work with you.
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