Patient Blog

What is a Leaky Brain?

It's difficult to imagine a leaky brain. But what is commonly referred to as a leaky brain is when the blood brain barrier (BBB) is compromised. It's about what leaks into the brain, not what leaks out! I'll explain this in just a bit, but before I do, I want to make sure there's an understanding as to what exactly is a leaky gut....because they are definitely connection. And you likely cannot fix a leaky brain without fixing the leaky gut.

Leaky Gut - Hyperpermeability

You hear the term leaky gut, but what exactly does that mean? You probably know that the nutrients from the food you eat get absorbed into the blood stream in the small intestine. The middle part of the small intestine in called the jejunum. It's here where micronutrients enter the blood stream.

In the early part of the small intestine, the duodenum, is where digestion primarily occurs and macronutrients are broken down into micronutrients if digestion is occurring as it should. Fats break down into fatty acids, carbohydrates into simple sugars, and protein into amino acids.

We have villi, which are little finger like follicles, that have tight gap junctions that only are supposed to allow micronutrients through to the blood stream. But when these villi get damaged, the junctions get wider and things like waste and undigested food particles leak into the blood stream. There are many things can that damage villi including overeating, poor digestion, a bacteria or fungal overgrowht and alcohol consumption for example.

Small Intestine

When the villi are no longer the gate keeper to your blood stream, and waste, toxins and undigested food particles enter the blood stream. If too toxic, the blood will not tolerate the toxins and will kick it out into the extra cellular fluid. And these toxins in your extra cellular fluid and blood causes internal inflammation and puts your immune system into overdrive.

Leaky Brain - Blood Brain Barrier

Now for the leaky brain...similar to the barrier we have in the gut that's designed to only allow micronutrients to be absorbed into the blood stream, we have a barrier that protects the brain. The blood-brain barrier (BBB) is a complex regulatory system and is both a blessing and a curse. A blessing because it regulates brain homeostasis and protects the brain from toxins and pathogens. A curse because it presents an obstacle to drug delivery to the brain for treating disease.

Major functions of the BBB include the transport of nutrients and protection of the brain from toxic compounds. There are several substances that are willingly allowed entry into the folds of the brain. And the secret password has to do with the molecular size of the traveler. Anything under about 500 daltons (which is an atomic mass unit), is allowed entry — whether it's safe or not. So, what might this include? Well the following substances are allowed entry for good reason:


~ nutrients
~ water
~ oxygen
~ carbon dioxide

The barrier keeps the nervous system safe from exposure to substances in the rest of the body and bloodstream. The brain is in part, protected from the dangerous substances that find their way into our bloodstream. Note that I said "in part" because there are some substances that hijack their way into our brains and some conditions that make the brain more leaky or permeable to this unwanted exposure.

The blood brain barrier can be broken down or allow larger particals to enter because of things like high blood pressure, the stress hormone cortisol, endothelial dysfunction, infections, microwaves and radiation, trauma, oxidative stress, blood sugar dysregulation and inflammation. Recent reports also note the negative impact of alcohol, prescription drugs, elevated homocysteine, and nutrient deficiencies as being contributing factors to blood brain barrier integrity loss.

Ironically, pretty much everything noted above can also be a symptom or cause of a leaky gut. Hmmmm...

Once that protective barrier stops being the gate keeper for what can enter the brain, or becomes ‘leaky’ or more permeable, there are all sorts of substances that can gain entry that should not have access to that delicate and impressionable tissue.

All diseases begin in the Gut!
– Hippocrates, 460 – 370 BC

The gut-brain axis (GBA) consists of bidirectional communication between the brain and the gut. Due to this connection via the Vagus nerve, gut microbiota can greatly influence our cognitive functions, such as learning, memory and decision making processes, as well as emotions and behavioral patterns.

Additionally, if our guts are leaky, inflammation will ensue. And this systemic inflammation creates breaches in the blood brain barrier. Because of the research that links leaky gut to neurologic symptoms, maintaining a healthy digestive tract may be an optimal strategy for supporting a well-functioning brain.

Quite often leaky brain syndrome is related to leaky gut syndrome. Both conditions are caused by the inflammation. The same factors that cause inflammation in the gastro-intestinal tract, like food sensitivity or imbalance of bacteria, often cause the inflammatory processes in the entire body and cause weakness of the blood brain barrier.

Once this barrier becomes compromised the brain can fall victim to damage from environmental toxins, like heavy metals, bacteria and more. In extreme cases with leaky brain symptoms one can start to experience major neurological or psychiatric conditions like ADD/ADHD, autism, chronic pain, depression and other mental illnesses.

As it’s fairly common to have leaky brain and leaky gut syndrome at the same time, and it is usually a good idea to focus on the treatment of both conditions at once. An anti-inflammatory diet including ample antioxidants and life style modification leading to decrease exposure to toxic factors must be implemented in the treatment of Leaky Brain syndrome. And most importantly, we must heal and seal the gut.

There’s a quote by Dr. Maya Shetreat-Klein, an integrative pediatric neurologist whose book the Dirt Cure is worth reading: “the gut is the soil where the brain grows.” I love this quote!