As a migraine sufferer, I was all too excited several years ago when the local hospital hosted an expert panel on migraine remedies which included diet. The 45 minute presentation covered the basic physiology, briefly mentioned chocolate and alcohol, and then spent the bulk of the time on medications – Aspirin, Excederin, Midrin, and Fioricet. During the Q&A I asked about omega-3 PUFAs since they are known to inhibit COX-2. One expert replied that she was unaware of any research on PUFAs or COX-2 for migraine. I appreciated her congenial reply, but sat down disappointed. Most of the medication identified did only one thing in the body – inhibit COX-2.
Let’s start at the beginning. Migraine is a complex condition with many subclasses including with aura (Classic,) without aura (Common,) chronic, retinal, and hemiplegic migraine.1-3
Whatever the name, for the 10-15% of Americans who suffer from them, migraines mean episodic, intense headaches, often with nausea and light and sound sensitivity. In all cases, it affects our quality of life and ability to work.4, 5
While medication remains the primary focus of migraine treatment, its use as the primary treatment has its own concerns. There’s now a class of chronic migraine called medication overuse headache (MOH) where overuse of pain medication can actually cause near daily headaches.6-8
This has led many to seek alternative treatments.
Diet may help. Migraineurs – a term that makes it sound like an exclusive club with a very low voluntary applicant pool – often cite dietary triggers for their migraines. The most common are alcohol, chocolate, cheese, caffeine, MSG and fasting.9 On the other side of the coin, dietary elements such as magnesium and omega-3 fatty acids may be therapeutic.10
Unsurprisingly, all of these dietary elements fit with a healthy, Paleo Diet lifestyle. So let’s take a look at the physiology of a few key elements of the Paleo Diet that can help you spend less time at the ”Migraineur Club House.”
MIGRAINE 101: DON’T GET HYPEREXCITED
There are many theories about the cause of migraines, but the most widely accepted is the neural hyperexcitability theory. Backed by recent MRI studies, it proposes neurons in the trigeminal-vascular region of the brain’s cortex become inappropriately activated, releasing a series of neurotransmitters that cause vasodilation, mast cell degranulation, increased permeability, platelet aggregation, inflammation, and ultimately pain.2, 9, 11-14 Recently, some suggest hyperexcitability is a result of a dysfunction in sodium-potassium transporters.15
For some, their migraine is preceded by a visual aura. This aura is caused by an initial depolarization of the neurons referred to as Cortical Spreading Depression.2, 15
That’s a very short summary of a very complex process. The take home message: an imbalance in excitation signals, neurotransmitters, and electrolytes may be at the root of your migraine pain. Dive in deeper with the references listed below.
POLYUNSATURATED FATTY ACIDS: MIND YOUR 3S AND 6S
While living out of the medicine cabinet may not be the best long term strategy, it’s important to point out that NSAIDs, such as ibuprofen, are very effective at reducing acute migraine pain.1, 4, 16 They do one thing – prevent the formation of molecules called prostaglandins by inhibiting a key enzyme called cyclooxygenase (COX).
So, it’s not surprising prostaglandins have been linked to migraine.1, 17-21 Simply injecting prostaglandin E2 (PGE2) into both healthy subjects and migraine sufferers was enough to cause migraine pain.22-25 The fact that pain was immediate, indicates that PGE2 may actually be the direct cause of pain for sufferers.22
But how does this relate to diet?
Prostaglandins are created from the polyunsaturated fatty acids (PUFAs) we eat.1 Our bodies are not particular – they will use whatever type of PUFA is available. But we end up with very different prostaglandins depending on whether we consume more omega-3 or omega-6 PUFAs.26
The figure below shows the types of prostaglandins (and other eicosanoids) formed from arachidonic acid (omega-6) verses EPA (omega-3).26
PGE3 and PGI3 from omega-3 PUFAs may actually help prevent both the inflammation and electrolyte imbalance that causes migraines.15, 26, 27 In fact, they have anti-inflammatory benefits for many chronic illnesses including cancer and heart disease.28-32
By contrast PGE2 and PGI2 from Omega-6 PUFAs are pain-causing. Hence they are the targets of most over-the-counter pain killers. These prostaglandins and their precursor arachidonic acid are elevated during migraines and may sensitize of the trigeminal nerve which is the location of migraine pain.1, 15, 19, 20, 33, 34 In fact, the highest level of PGE2 receptors in the body are found in the trigeminal nucleus caudalis.22
Fortunately, when diets are high in omega-3 fatty acids such as EPA from fish oil, the good prostaglandins tend to supplant the bad.26
So, why then was it that studies of omega-3 supplementation have had mixed results for migraine?35-37
Due to the huge increase in vegetable oils and grain fed livestock in the western world, the ratio of omega-6 to omega-3 PUFAs in our diets have risen to 10:1 from an estimated 3:1 or even 2:1 in Paleolithic times.26, 38-40
To see if the ratio influenced migraines, a 2013 study by Ramsden et al, not only increased omega-3 in Migraineurs’ diets, but reduced the omega-6 content. The pain improved significantly. Interestingly, the investigators included a second group that only reduced omega-6 PUFAs in their diet. While not as dramatic, this group also improved.35
Issues with the high ratio of omega-6 to omega-3 fatty acids in the western diet go beyond migraines. The ratio has been associated with many chronic conditions including depression (due to its influence on serotonin), rheumatoid arthritis, inflammatory bowel disease, asthma, heart disease and chronic inflammation.26, 27, 38, 41
A Paleo Diet promotes a better omega-3 to omega-6 ratio. The best source of omega-3 PUFAs is EPA from fish, but other sources include walnuts, lean meats, and some vegetables such as broccoli and spinach.42 Just remember that the shift from omega-3s to omega-6 PUFAs in our bodies takes time – from 6 – 18 weeks.43
MAGNESIUM: THE PAINFULLY FORGOTTEN ELECTROLYTE
Magnesium is sometimes referred to as the “forgotten electrolyte” since it is frequently overshadowed by calcium in the research.44-46 Magnesium is involved in over 300 functions in our body, which means it is not a nutrient we want to forget about. Yet almost 48% of Americans eat less than the RDA.15, 44
Most magnesium is found in our bones and cells with less than 1% in our blood,45 which means that a blood test for magnesium isn’t very effective.47 Up to 14% of the population may be deficient and this deficiency has been associated with many chronic conditions including heart disease.48
Evidently, magnesium deficiency has been clearly linked to migraines.9, 47, 49, 50 In multiple studies, migraine sufferers had lowered levels of magnesium in their blood, saliva, and cerebrospinal fluid during attacks.51-56
Magnesium affects many processes linked to migraine including neurotransmitter release, serotonin receptors, inflammatory mediators, and the inhibition of platelet aggregation.56-63 It may even block some of the inflammatory effects of omega-6 PUFAs.44
Magnesium supplements help migraine sufferers.51, 56 Even more strikingly, people going to the emergency room with migraine pain are frequently treated with an infusion of magnesium sulfate which is more effective than the pharmaceutical treatments dexamethasone and metoclopramide.47, 57
Unsurprisingly with current migraine research pointing to electrolyte imbalances, the “forgotten electrolyte” may play a key role in migraine hyperexcitability.15
Sodium-potassium imbalance may trigger migraines, but overactive calcium channels could be the cause.2 High levels of calcium in the brain make neurons easily excitable.2, 44 Magnesium is a key regulator of calcium and might be able to control this calcium-induced hyperexcitability.44
In fact, in a review of migraine hyperexcitability, Welch proposed that the changes in magnesium levels during a migraine may be an attempt by the brain to restore electrolyte balance.2
Here again, migraines show why a properly balanced diet is far more important than just popping supplements.
With the concern over osteoporosis, daily calcium consumption has been increasing over the past four decades.44 This Western focus on calcium has led to one of the biggest criticisms of the Paleo Diet for its elimination of dairy. This is in spite of recent research questioning the benefits of high calcium intake and worse, linking it to heart disease.64-68
What may be more important than the absolute calcium level is the ratio of magnesium to calcium in the diet which has been decreasing.44 Not something to overlook considering increased magnesium consumption reduced all-cause mortality associated with high calcium intake.69
Worse yet, consuming too much calcium can exacerbate magnesium deficiency.70
The higher calcium-magnesium ratio of the Western diet may contribute to a variety of chronic conditions beyond migraine, including stress, metabolic syndrome, Type II Diabetes, hypertension and vascular disease.44
The Paleo Diet promotes a better calcium-magnesium ratio through the consumption of foods high in both including almonds, cashews, green leafy vegetables, and fish. While research is limited, it is believed that alcohol and sugary drinks can limit magnesium absorption.
ELIMINATING DIETARY PAIN
Food sensitivity remains one of the most common migraine triggers,71, 72 but the foods tend to be highly individual. A food diary is one way for migraine sufferers to identify their triggers. Though this can be difficult since foods interact and sometimes the migraine appears a day or more after eating the culprit foods.9
Fortunately, there may be another way to identify your triggers. Food that causes an IgG antibody response has been associated with migraines.9 Studies eliminating these foods have produced dramatic results with up to 93% of participants becoming headache free.71, 73, 74
This study found that an IgG-elimination diet also helped Irritable Bowel Disease, another condition affected by dietary imbalance.71, 75 Up to 50% of people with IBS suffer from migraines76 with neural hypersensitivity77 and mitochondrial DNA mutations75 linked to both.
We frequently recommend Paleo Dieters suffering from chronic conditions try an elimination diet. Seeing your allergist to help you identify IgG-provoking foods may be a shortcut to help you get past migraine pain.
Certainly PUFAs and magnesium have dominated the literature on diet and migraines – to the point that they were used as a proof of concept for literature research.78 But this doesn’t mean they are the only dietary factors. Both low fat79 and ketogenic diets80 improved migraine symptoms. Migraine hyperexcitability can be affected by the sodium-potassium balance in the diet and hydration status (with dehydration and hypohydration causing migraines).15
The underlying message is migraine pain may be a disease of imbalance. So, while I’ve reached for the Excedrin bottle more than a few times to get through my day, a balanced diet more attune with our evolutionary make-up may ultimately be what keeps us Migraineurs away from the medicine cabinet altogether.
Trevor Connor is Dr. Cordain’s last mentored graduate student and will complete his M.S. in HES and Nutrition from the Colorado State University this year and later enter the Ph.D. program. Connor was the Principle Investigator in a large case study, approximately 100 subjects, in which he and Dr. Cordain examined autoimmune patients following The Paleo Diet or Paleo-like diets.
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