Leaky Brain: Astonishing New Discovery

While knowledge of ‘leaky gut’ is gradually entering the mainstream, the closely related condition of ‘leaky brain’ is only just beginning to gain recognition.

Leaky gut is a term used when the intestinal wall has increased permeability allowing particles to get through into the blood stream that otherwise wouldn’t gain access.

If you suffer with depression, anxiety, poor memory and concentration, brain fog, autism, schizophrenia, you should consider whether you have a leaky brain.

To heal a leaky brain, you have to start with sealing and repairing your gut lining first.

The gut brain axis

The gastrointestinal system contains its own nervous system known as the enteric nervous system, along which, hormones and immune signals are exchanged.

Communication works both ways – brain to gut and gut to brain, therefore any disturbance in the brain is expressed in the gut and vice versa.

Think of it a bit like a motorway, where the cars are the messages and the road is your nervous system.

We talk about this more here: Brain Health Begins In The Gut and How Stress Wreaks Havoc on Your Microbiome

An example of this connection is frequently seen in autistic patients, who are renowned for also suffering with gastrointestinal disorders such as diarrhoea and chronic constipation to inflammatory and irritable bowel conditions.

The role of zonulin in leaky gut

Zonulin is a protein that can open tight junctions between cells that line your intestines. If triggered too much, it can lead to undesirable particles entering your blood circulation, including zonulin itself.

The blood brain barrier (BBB) around your brain is just that, a barrier, stopping stressors (undesirable particles) from entering and causing damage to your brain and nervous system.

The BBB works much the same as the intestinal lining when stimulated by zonulin. This means that if zonulin enters your blood circulation due to leaky gut, it can travel up to the BBB where it causes tight junctions to open.

This weakens the protective shield around our brain, allowing undesirable substances to enter, such as toxins released by bad bacteria in our gut. This interferes with our delicate brain chemistry and leads to inflammation.

For the science boffins reading this (me included!) I am going to explain this in more detail going through the 4 steps which result in a leaky brain, for those not so fussed on the geeky detail, scroll down to the WHAT CAN I DO section at the end.

Leaky brain

High zonulin levels in the blood are also associated with conditions such as coeliac disease, rheumatoid arthritis, inflammatory bowel disease, asthma, fibromyalgia, headaches, eczema and frequent colds.


1. Zonulin Release

  • The release of zonulin is triggered by endothelial cells (cells lining the intestines) exposure to gliadin and pathogenic bacteria. Gliadin is a protein found in gluten.
  • Zonulin can open the tight junctions between cells.
  • Leading to increased intestinal permeability
  • Increased passage of stressors into the lamina propria, which lies below the intestinal wall

2. Immune response – development of leaky gut

  • Increased exposure to stressors triggers an immune response and inflammation
  • A vicious cycle develops where inflammation and tissue damage further increase intestinal permeability, leading to even greater passage of stressors worsening the situation
  • Unbalanced immune responses and increased inflammation in the gut also interact with the HPA axis (hypothalamus-pituitary-adrenal axis) and neurotransmitter metabolism
  • Stressors enter circulation, these include toxins, endotoxins, pathogens, antigens, inflammatory markers and antibodies

3. Blood brain barrier dysfunction – leaky brain

  • The blood brain barrier contains tight junctions
  • Zonulin that has travelled in the blood from the gut binds to zonulin receptors on the tight junctions of the blood brain barrier
  • The tight junctions open
  • The same thing happens as in the gut: stressors enter the brain including pathogens, toxins, inflammatory markers and antibodies

4. Neuro-inflammation

  • Damage caused to brain cells from the toxins, pathogens etc
  • Immune response is stimulated in the brain
  • Inflammation develops further perpetuating the cycle as more stressors enter, leading to neuro-inflammation
  • Chronic neuro-inflammation has been associated with many conditions such as mood disorders, Alzheimer’s disease, autism, dementia, schizophrenia, mental fatigue, brain fog, anxiety, depression and cognitive decline

leaky gut infographic


3 ways to reduce leaky gut and leaky brain:

  1. Avoid gluten in your diet. Gluten contains a protein called gliadin that stimulates zonulin, which in turn increases permeability (leakiness) of our gut and blood brain barrier.
  2. Eat zinc rich foods such as oysters, spinach, pumpkin seeds and good quality dark chocolate (85% cocao). Zinc supports healthy immune function and aids healing. It is also associated with enhancing the tight junction barrier.
  3. Take a probiotic supplement or eat fermented foods. Probiotics modulate the immune response and down regulate inflammation, promoting gut healing. They also produce short chain fatty acids which may reverse the detrimental effects on brain cells as well as protecting the gut lining.

If you would like to find out if you have leaky gut and leaky brain, you can have your blood zonulin levels tested. We offer this as part of our coaching program.


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48 thoughts on “Leaky Brain: Astonishing New Discovery”

  1. I never knew about all of this. This is so crucial when it comes to having a healthy body and mind while become a healthier version of yourself.

  2. Really informative and I like your writing style, you explain in a way that could be understood by everyone, I’ve always heard of the benefits of zinc will try to improvise more in my diet, thanks for sharing

  3. I’ve never heard this before but this is very educative that giving knowledge to the people awesome. Taking care of our mental health is very important nowadays.

  4. I think it’s interesting how the brain and gut are connected in that way. It does make sense, since we are what we eat. I know I feel better mentally when I eat less junk.

  5. Wow! Super interesting and informative as always! I had no idea that a person’s brain and gut were so linked like that. I’m also really going to increase my intake of spinach and pumpkin seeds. Great post!

  6. Very informative and not something I would have heard from which is interesting because I am in the process of testing to see if I am lactose intolerant.

  7. Caressa Walker

    I love how you provided extreme detail in the things that cause our brain to leak and even better when you gave us simple things to do to prevent it .

  8. Science is in a continuously discovering! Like a black whole: never ending. Each day brings new things to discover!

  9. I think it is absolutely fascinating that this information is available. I could just sit and delve into this material to where I can’t get up. Totally makes me Wow in my seat. I love the photos too of the details inside the gut, small intestine etc… Truly a photo captures a thousand words. Thank you so much for all of this information to enable us to take better care of our wonderful gift the creator has given us.

  10. So interesting! I just added my email below. I have just lost 55 lbs. and feel so much better! I would like to further refine my diet, but lack the knowledge. Would love to have my zonulin level checked. Did not even know that existed to even ask my doctor to order it!!! Thanks so much!! I look forward to learning lots from you!!

  11. I have suffered with leaky gut for years, most uncomfortable. I also sugf red from lack of words, brain f🧠 g and lately lapse in moments. Working on getting balanced, supplements, bett r choices and no grain. Most recent added zinc with copper into my body and have found the love for raw fermented sauerkraut again. Crossing fingers. Thanks for all your info , just added myself with email address.
    Happy Days, E

  12. So happy to see this life-changing information making the rounds. I have seen so many of my clients lives changed by repairing their gut and eating the right food. Thanks for passing this on to your audience. GREAT info

  13. Hello Lynette, lactose intolerance can make leaky gut worse, but that isn’t to say that it will cause leaky gut. If you have any symptoms of leaky gut then my suggestion would be to remove dairy completely from your diet whilst you heal and seal your gut lining. You can then introduce diary small steps at a time and take note of any reactions or symptoms. Digestive enzymes may be beneficial for you as well as fermented milk such as kefir as the lactose has already been broken down during the fermentation process.

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