This is the second post in a series about migraines. Start with the first post, about hormonal triggers.
Migraines from barrier dysfunction
This review and this review show the correlation between migraines and gut diseases, such as irritable bowel syndrome, h.pylori infection, inflammatory bowel disease, celiac disease, gastroparesis, and colic, among others.
There are many ways that gut disease can trigger migraines. However, all have one common mechanism at play:
A permeable (leaky) gut barrier
You may have heard the term “leaky gut.” Actually, it’s a real thing, called intestinal permeability in medical terms. In a nutshell, the cells that make up the lining of your intestines have tight junctions, therefore nothing undesirable can “leak” through. Your intestinal lining is thin – just one cell in depth so that you can assimilate nutrients easily. That’s why you need tightly controlled junctions between these cells. Leaky gut is when these junctions are loose.
What leaks through?
→ Food protein molecules that are not completely broken down. These proteins trigger your immune system to mount an attack, which can include your own body tissues (autoimmunity). This creates widespread antibodies plus immune complex and inflammatory molecules, all of which can trigger migraines. Besides migraines, if you have food intolerances or autoimmunity, it’s likely you have leaky gut.
→ Toxic bacterial byproducts called LPS (lipopolysaccharide) endotoxins (toxins produced from inside your body). When LPS endotoxins leak through your gut, they cause widespread inflammation, as well as pain. If you have unresolved pain such as migraines or fibromyalgia, chances are high that you have leaky gut.
Causes of leaky gut*
Dysbiosis (microbial imbalance) is the primary cause
If you have a suboptimal gut microbial population (overgrowth of undesirable bacteria, yeast, or parasites, or not enough beneficial bacteria), then your gut lining is affected in many ways:
- Beneficial bacteria secretions make your healthy mucosal lining! Lack of beneficials = lining impairment.
- Dysbiosis makes your lining irritated, inflamed, damaged, and permeable.
- When you restrict carbohydrate and fiber too much, bacteria can feed on your protective mucosal got lining!
- Fungal overgrowth can embed into your gut lining, and provide houses (vacuoles) for bacteria and viruses.
- Beneficial bacteria make short-chain fatty acids like butyrate that are natural lining anti-inflammatories.
- Certain types of beneficial bacteria that make up your lining also knock down invasive pathogenic bacteria, yeast and parasites, and keep dysbiosis in check.
- Your gut immune system (GALT) provides important immunoglobulins that fight pathogens. Dysbiosis lowers these immunoglobulins.
There’s another way “dysbiosis” can cause migraines. You can have an overgrowth of bacteria that turn nitrates into nitric oxide, a headache trigger. In fact this study showed that nitric oxide was higher in the bloodstream of migraine sufferers!
Other causes of leaky gut
- Alcohol: Alcohol damages your gut lining, and allows endotoxins to leak through. Measurements of LPS endotoxins are higher with alcohol disease damage.
- Medications: The most common are:
- Antibiotics, which significantly change your gut microbiome for the long term.
- Nonsteroidal anti-inflammatories (NSAIDS) like aspirin, ibuprofen, and prescriptions like meloxicam. All the NSAIDs directly damage your gut lining.
- Antacids, H2 blockers and proton pump inhibitors that block reflux. All of these medications are meant to be used to short-term, no more than two weeks. Beyond that, you lose protective stomach acid that breaks down your proteins and kills incoming microbes. These medications cause malabsorption of nutrients and change the pH of the food that enters your small intestine. That means you won’t secrete your own enzymes and bile because this signaling needs a precise pH to work. Interfering with pH in your stomach will interfere with your pH throughout your whole digestive tract.
- Gluten: In all people, gluten increases a lining protein called Zonulin, which signals a loosening of your intestinal cell tight junctions (TJs). Some people can handle this, but anyone with celiac disease or non-celiac gluten sensitivity cannot handle this without gluten proteins leaking through and wreaking havoc.
- Other inflammatory foods for you. This must be determined on a case-by-case basis.
- Stress: There are a myriad of explanations and studies as to how stress affects gut permeability.
- Constipation: This is likely due in part to microbiome imbalances. This new 2017 study is the first that shows treating constipation improves leaky gut.
What to do?*
Get comprehensive assessment for food intolerances, dysbiosis, and intestinal permeability. I have seen time and time again many migraine sufferers lesson or resolve their migraines by cleaning up gut issues. This includes me! Work with a Functional Medicine practitioner, this is too complex to assess and treat on your own. There are excellent tests that influence individual treatment, such as the GI Map, the SIBO breath test, and food intolerance tests.
After an assessment, your Functional Medicine practitioner will apply the four “Rs” of gut treatment: Remove food irritants and microbial overgrowths, Reseal the gut lining, Reinnoculate beneficial bacteria through food, prebiotics, and specific strains of probiotics, and Replace anything needed for optimal digestion.
Blood brain barrier
Your blood brain barrier (BBB) is similar in structure to your gut barrier. Both are composed of endothelial cells with tight cellular junctions. These two barriers, along with other endothelial barriers in your body, are regulated by signaling proteins such as zonulin (activated by gluten) and occludin, among others.
When your blood-brain barrier is disrupted, then LPS endotoxins, inflammatory molecules, and nitric oxide can leak through into your brain and cause inflammation. Neuroinflammation can trigger migraines.
Scientists used to think migraines were either neurological (nerves) or vascular (vessels), but now they realize migraines have both components. The BBB is a complex neurovascular unit consisting of central nervous system (CNS) endothelial cells which separate the lumen of blood vessels from the brain. Tight junctions seal the endothelial cells of the BBB.
When your BBB is leaky, all kinds of neurological symptoms can occur, including migraines, dizziness, brain fog, sleep disturbances, fatigue, anxiety, and depression. Over time, neurological autoimmunity and degeneration can occur, including cognitive impairment and dementia.
Causes of leaky brain*
Alcohol, gluten, food intolerances, microbial endotoxins, and stress: These factors are common in that they can trigger permeability in both the gut and brain barriers.
Pain: Nerve pain in your body, from injuries, neuropathy, sciatica, rheumatoid arthritis, multiple sclerosis (and more) increases enzymes called matrix metalloproteinases (MMPs). MMPs are really important in the development and flexibility of your nervous system. However, nerve pain can raise MMP levels too much, which then causes a disruption in your blood-brain barrier. The latest research shows higher MMP levels in migraineurs.
Blood sugar imbalances: High or low blood sugar disrupts the integrity of the BBB.
Systemic infection and/or inflammation: There are a myriad of pathways that infection and inflammation disrupt your BBB, such as cytokines, prostaglandins, nuclear factor kappa B, MMPs, and more. This recent 2017 study outlines all of these pathways.
Traumatic brain injury (TBI): Shown to disrupt the blood-brain barrier.
Oxidative stress: Disrupts blood-brain barrier and causes neurodegeneration.
What to do?*
Assess brain inflammation and oxidative stress with the organic acids test. You can test the barrier proteins zonulin and occludin, and you can test for brain antibodies. In my opinion, it’s best to start with the gut, which is easier to assess. Plus, if your blood-brain barrier is disrupted, the first approach is to work with strengthening your gut barrier. Furthermore, barrier control mechanisms are similar, so if you improve your gut barrier you will improve your brain barrier.
So, start with your gut barrier, described above. Next, address brain inflammation and oxidative stress with the organic acids test. Work with a Functional Medicine practitioner to improve these if they are high. Lastly, apply approaches that further seal your BBB. Some of my favorite research-based blood-brain barrier sealers include turmeric, resveratrol, ashwagandha, and rhodiola. It’s worth mentioning that glutathione is an important antioxidant for the brain and that CBD (cannabidiol) and flavonoids are excellent agents because they cross the blood-brain barrier and reduce brain inflammation.
*These are not absolute lists of causes or treatment approaches.
Also, some people have more complex triggers of barrier disruption and migraines. This could include inflammation from mycotoxins (mold), that can cause chronic inflammatory response syndrome (CIRS). In addition, it could include toxins from the environment, such as chemicals and metals, that leak through your barriers. Lastly, you could have complex infections and co-infections, such as those that exist in long-standing cases of Lyme disease. For these more serious cases, it’s important to find a specialist to work with.