You probably have heard about “leaky Gut”, right? It is a gastrointestinal condition that your Gut can be punctured, which then impacts how well you digest your food and absorb the nutrients, how sensitive you are to possible allergens, and how much inflammation your food may cause. You may have heard of leaky Gut in terms of “intestinal permeability”, which might make it seem like your gut shouldn’t be so permeable. But the truth is that your gut is naturally and selectively permeable, allowing helpful compounds like nutrients to pass into the body while keeping harmful toxins and pathogens out. When this process fails, and the membrane of your GI tract becomes more permeable than it should be, it’s called leaky gut.
But today we will talk about “leaky brain”, which has a lot in common with leaky Gut. Just like yourgastrointestinal (GI) tract has a protective barrier protecting it from its surroundings, your brain has its own casing that protects it from your body and bloodstream. It’s called the blood-brain barrier (BBB).
The Blood-Brain Barrier (BBB)
Leaky brain issues are just as common because your blood-brain barrier is also semi-permeable. Your brain needs things like glucose, amino acids, fat-soluble nutrients, and ketones to function properly, and gets them through the semi-permeable blood vessels that shuttle them into your noggin. Your brain also needs the BBB to keep harmful toxins, infectious pathogens, and errant immune cells out. And, when the barrier is compromised, the floodgates open to all manner of nasty invaders, which can cause brain fog, depression, anxiety, and a host of neurodegenerative diseases, like dementia, Parkinson’s, and Alzheimer’s. So basically, when the blood-brain barrier is punctured, ruptured, or loosened, things like heavy metals, toxins, molds, fungi, and chemicals produced by our post-industrial world seep in and wreak havoc.
The blood-brain barrier, at its most basic and well-recognized level, is formed by brain capillary endothelial cells (simple squamous (flat) cells that line the inside walls of blood and lymphatic vessels). It includes anatomical, physicochemical, and biochemical mechanismsthat control the exchange of materials between blood, brain, and cerebrospinal fluid, which makes it the main physical barrier through which nutrients, hormones, and various chemicals pass from your brain to your blood system, and vice versa. Caffeine, for example, crosses the barrier quite easily, and, as you’ll learn, is actually potently beneficial for it.
The barrier maintains the extracellular environment of the central nervous system and brain through three main lines of defense:
- The physical barrier itself between blood and brain,
- Transporters that mediate the flow of compounds from the brain to the blood, and,
- An enzymatic barrier that contains neurotransmitter and toxin metabolizing enzymes in the endothelial and epithelial cells of the brain and blood, respectively.
Most of the research on the BBB in the 20th and 21st centuries, however, has focused on the first layer, the physical barrier, usually in order to learn how to deliver drugs more effectively to the central nervous system. This is the part of the BBB I’m going to cover here.
The endothelial cells lining blood vessels are only one layer thick. Some of the largest vessels, the arteries and the veins, are also surrounded by thick walls of connective tissue and layers upon layers of smooth muscle cells; but the vessel walls themselves are lined by a thin, single sheet of cells. This ultra-thin sheet determines the passage of every substance from the blood to the rest of the body — including the brain. So when it gets damaged, things escalate fast.
Like every other cell type in your body, endothelial cells can divide and repair damages in the sheet wall of a given blood vessel. If left to themselves, they’ll live out a cell lifetime that ranges from a couple months (liver endothelium) to several years (brain endothelium). But when they’re exposed to detrimental compounds and physiological circumstances, they can die prematurely and will need to divide quickly to repair the vessel wall. And when the vessel wall is exposed to this state without break, the BBB will be weakened overall, which can lead to all kinds of problems, including the leakage of plasma proteins into certain regions of the brain. This can cause exacerbated inflammation in the brain, and long-term, chronic inflammation in the brain can only cause problems.
What weakens the blood-brain-barrier?
1. Sleep Deprivation
Your body needs you to sleep appropriate amounts of each sleep phase, in order to properly regulate the functions and integrity of the BBB. In particular, loss of REM (rapid eye movement) sleep damages much of this function.
If you’re sleeping less than, in most cases, the recommended 7 to 9h per 24h, your brain will suffer. A group of researchers studied the effects of chronic sleep restriction (CSR) on mice in a test designed to mimic a common pattern of human sleep loss. They found CSR not only diminished endothelial and inducible nitric oxide synthase, endothelin1, and glucose transporter expression in brain microvessels of the BBB, it also decreased 2-deoxy-glucose uptake by the brain, a sugar needed to maintain proper electrical signaling and membrane potentials. This all coincided with an increase of paracellular permeability of the BBB, leaving the brain more vulnerable to invasion.
2. Excessive Alcohol Intake
Another cause that was already mentioned is excessive alcohol intake. Studies in the past have indicated that long-term alcohol abuse can lead to massive functional and morphological changes in the CNS, including neurodegeneration that ranges from minor dendritic and synaptic changes to full-on cell death. This occurs through oxidative stress on neural cells. The alcohol you drink is essentially ethanol (EtOH), which, among other things, enhances reactive oxygen species (ROS) that damage brain cells. Chronic exposure to alcohol also increases the expression of CYPE1, the enzyme that turns EtOH into ROS and acetaldehyde (the substance that causes the feeling of hangover). And, both EtOH and its metabolite acetaldehyde decrease the tightness of the BBB, which is exactly what should be avoided.
3. High-Blood Pressure
One study observed rats and found that the BBB dysfunction present in the rats was quite clearly related to the combined effects of elevated blood pressure and cerebral vasodilation (the widening of blood vessels in the brain). And, unfortunately for all of us, high-blood pressure is caused by a number of things, including stress (from anywhere), poor breathing, poor diet, lack of sleep, and more. Considering one in every three adults in the U.S. has high blood pressure, this should be taken seriously.
How to fix a leaky Blood-Brain-Barrier
Before you do anything else, you need to sleep more. The first sleep study mentioned above also found that at the end of a 6-day period of sleep deprivation, the permeability of the BBB was restored to baseline after just 24 hours of recovery sleep. Sleep loss is known to impair the immune system, while simultaneously increasing levels of pro-inflammatory mediators. It also increases sympathetic nervous system activity and causes endothelial dysfunction. So to maintain homeostasis, the general health of your body, and the health of your BBB in particular, you need to get more sleep each day, between 7 and 9h per 24h period.
2) Limit Alcohol
As you learned above, this one is huge. While a glass of wine a day can cause low doses of ethanol to migrate across the barrier and trigger good endorphins and relaxing neurotransmitter receptors, higher amounts of alcohol can, obviously, cause high-doses of ethanol, along with acetaldehyde, to damage brain neurons.
3) Control Blood Pressure
Both acute and chronic hypertension increase blood-brain barrier permeability. Dark chocolate, high-dose garlic, magnesium, potassium, and even hand-grip training can all help to lower blood pressure. And luckily, you don’t have to eat an entire bowl of elephant garlic to reap the benefits. There’s a form of garlic extract called allicin, which is the main active component of garlic, that’s a far more efficient way to get the brain-boosting benefits of this common ingredient. As far as grip devices go, you can take a hand-grip strengthener with you in the car or airplane or train, and just keep squeezing it. There’s even a commercial device called Zona that’s been clinically approved for treating blood pressure. It even digitally walks you through a squeeze-and-relax regimen.
4) Caution With High-Fat Diets
Rodents that were given a 40% saturated fat diet (from cocoa butter) experienced elevated blood-brain barrier permeability, but adding in either aged garlic extract, alpha-lipoic acid (ALA), niacin, or nicotinamide completely eliminated this elevation. Phytonutrient-rich plants and spices such as curcumin (from turmeric), astragalus root, cruciferous veggies like broccoli, brussels sprouts, and cabbage produce a similar healing effect. Fiber-rich plants are also beneficial. They allow you to consume high amounts of fat while minimizing some of its effects. Make sure you also start including lots of dark, leafy greens in your meals, like kale, spinach, or collard greens.
5) Drink Coffee and/or Tea
Caffeine is a noted protector of blood-brain barrier integrity, and may even help inhibit BBB disruption as a means of preventing Alzheimer’s disease.
Alpha-GPC, a type of choline that readily crosses the blood-brain barrier, is known to improve endothelial dysfunction. Inositol from egg yolks improves BBB integrity, berberine reduces its permeability and increases resistance to brain damage following head trauma, and vitamins B12, 6, and 9 restore it to equilibrium.
As mentioned, high magnesium intake can attenuate BBB permeability, even in test subjects who have been injected with an agent to induce leaky blood-brain barriers. You can get it into your system by taking it orally, or applying it topically either as a lotion or spray on the back of your neck and head.
8) Stimulate Your Vagus Nerve
Stimulating the vagus nerve with practices like singing, chanting, meditating, deep breathing, cold showers and even electronic stimulation, and a host of other lifestyle practices and biohacks can all decrease BBB permeability.
9) Limit Snacking
Ghrelin, a hunger-stimulating hormone that tells you it’s time to eat, can also improve BBB integrity. Specifically, it can reduce BBB breakdown after traumatic head injury. By avoiding frequent snacking and grazing, practicing intermittent fasting, and reaching to point of hunger, you get better BBB function.
10) Nourish Your Gut
One study observed the effects of a transplant of gut microbiota from healthy mice with perfect BBB integrity to unhealthy mice with a leaky barrier, and found that it did, in fact, restore the integrity of the damaged barriers. Luckily, you don’t have to get such transplants from other people — you can get the same results by eating more prebiotic fiber, taking quality probiotics, and eating fermented foods on a regular basis.
The final tip is simply… cold showers. This will affect everything from your appetite to your vagus nerve connection between the gut and brain, to temperature fluctuations that will cause a release of blood and nitric oxide in your brain, all of which will improve BBB integrity by overall suppressing mechanisms of BBB degeneration. Cold soaks, cold shower, splashing cold water on your face, it’s that simple.