GLUTEN AND “LEAKY BRAIN”: how gluten contributes to cognitive decline.
It is no secret that diet and nutrition are key for good health, and for a healthy brain. There is a profound difference in outcomes and health levels for those who adhere to a strict diet, versus those who eat whatever they like. Those who are careful about what they put into their bodies experience lower levels of pain and inflammation, more energy, more even keeled emotions, and better brain function. As an example, I see this time and time again in my Lyme patients who experience the cognitive and psycho-emotional issues we call “Lyme brain”.
Most of my patients want to do whatever they can to feel better, and dietary choices are in some ways the simplest changes they can make (note I said simplest, not easiest – for many following a special diet requires a lot of effort, organization and discipline). Chronic illness can be very disempowering, frustrating and overwhelming. Making changes in what you put in your mouth can help you regain a sense of control, and can be very empowering. Yes, restrictive diets are challenging, but I have seen the benefit time and time again.
There are certain things that I see as core principles for using nutrition to help the brain. One of the major one is avoiding gluten. Here is a key reason why:
Leaky Gut/ Leaky Brain
Most people are familiar with the concept of leaky gut. This occurs when the gap junctions between the cells of the small intestine open up, allowing larger particles than normal to escape into the blood stream. This can cause an immune reaction as the larger particles are viewed as intruders. Leaky gut can be caused by a number of different factors, including gluten intolerance and other food sensitivities, intestinal parasites, bacterial imbalance and Candida overgrowth. Essentially, anything that causes inflammation in the gut can contribute to leaky gut.
Did you know that there is increasing evidence of a phenomenon called leaky brain? The premise is much the same – the gap junctions between the cells of the blood-brain barrier open up, allowing the passage of undesirable substances into the brain. The blood-brain barrier provides protection for the brain. That protection is crucial otherwise the brain would be vulnerable and potentially exposed to a myriad of things that could be toxic and harmful to it. The goal of the blood-brain barrier is to allow the passage of oxygen, nutrients and fuel to the brain, and the removal or carbon dioxide, waste materials and toxins from the brain. It keeps chemicals and toxins out. In some cases, that protection works against us, such as when we would like a great penetration of antibiotics across the and to the brain; but for the most part we can be grateful for what it provides for us. Remember, in severe inflammatory states such as meningitis, the blood-brain barrier can get very porous, and all of a sudden all of those oral antibiotics that don’t work ordinarily can get in and work quite well. We also know that Lyme disease and other chronic infections create an inflammatory state, and that in itself can lend itself to some increase permeability of the blood-brain barrier.
There is emerging evidence that a leaky blood-brain barrier contributes to cognitive decline. Certainly, there is damage to the blood-brain barrier in post-mortem study of Alzheimer’s patients. A recent study used MRI imaging to evaluate blood-brain barrier permeability. Results demonstrated an age-related decline in the hippocampus, the area that is critical for learning and memory. The breakdown correlated with mild cognitive impairment, and with damage to pericytes in the blood-brain barrier, and with increase “leakiness” of the blood-brain barrier.
This is all fascinating, but how does it relate to our discussion on nutrition and brain function? Certain foods, surprise surprise, have been touted to be major contributors to leaky brain. That brings us to my number one nutrition tip.
Nutrition Tip #1: Avoid Grains, Especially Gluten
Let us start with perhaps the biggest culprit in promoting inflammation in general, and subsequently leaky brain. Gluten, in my opinion, is the most sinister of foods – there is study upon study showing its inflammatory nature and the detriment it causes the human body and mind.
Gluten stimulates zonulin. Zonulin is a substance that regulates the permeability of the lining of the brain and gut through activation of epidermal growth factor receptors and protease-activated receptors. It is through this mechanism that gluten contributes to leakiness of the blood-brain barrier. To simplify, gluten upregulates zonulin. Increased zonulin contributes to greater permeability of the blood-brain barrier. Greater permeability of the blood-brain barrier increases the passage of pro-inflammatory cytokines, heavy metals, environmental toxins and other harmful substances into the brain. This then leads to neurological and cognitive dysfunction – a laundry list of issues that looks staggering similar to the issues experienced by those with chronic issues such as Lyme disease, ADHD, autistic-spectrum disorders, depression/ anxiety and so on.
Of course, any food that provokes an IgG response (what we term food sensitivities or intolerances, rather than full-blown food allergies) can trigger the zonulin activation and contribute to leaky gut and leaky brain. Studies clearly show a relationship between food intolerance and depression via leaky gut and the triggering of inflammatory cytokines that come with it.
Searches of the literature reflect a wide variety of neurological issues being associated with gluten sensitivity – epilepsy, peripheral neuropathy, headaches, migraines, anxiety, depressive and mood disorders, attention-deficit hyperactivity disorders, autism spectrum disorders, and schizophrenia. And just because you do not have gastrointestinal issues when you eat gluten, do not think that you’re immune from the brain issues it can trigger. Studies show that gluten can lead to many neurological disorders, including epilepsy, multiple sclerosis, dementia and peripheral neuropathy, even in people with no overt digestive manifestations. In fact, one study showed that as many as 57% of people with neurologic dysfunction tested positive for anti-gliadin antibodies, indicating gluten sensitivity even in the absence of full-blown celiac disease.
Adopting a gluten-free diet is key for chronically ill patients. Actually, there is not one of my patients that I would think a gluten-free diet is not important. For more support and information on the logistics of eating gluten free, I would refer you to my first book, The Lyme Diet (it’s relevant even if you don’t have Lyme disease!) There are also a plethora of books and websites on eating gluten free, and a growing number of gluten-free foods available. Dr. David Perlmutter has written two fabulous books on gluten and the brain, including a very detailed description on the mechanisms of leaky brain. My favorite is Grain Brain: the surprising truth about wheat, carbs and sugar – your brain’s silent killer.
If ever you needed another reason for taking gluten out of your diet, this is it!! Leaky gut, leaky brain, and a host of inflammation caused by gluten will compromise cognitive function, memory, and potentially predispose to a number of neurodegenerative diseases.