You know what used to really irk me? When people would say, “there is no science to support changing your diet to help reduce migraine.” It doesn’t bother me much anymore as I have experienced the powerful effect of diet for myself as well as witnessed countless examples of diet helping people get significantly better. As a licensed professional (registered dietitian), I pride myself on only using evidence-based approaches to help people, but there are few studies to point to and say “A-ha!” I’m bummed that I have no solid response to the demand, “show me the science!” but I don’t let it get to me anymore.
So, let’s take a look at why there is so little data to support a migraine diet. First, diet studies are notoriously flawed. This is one reason why we see conflicting headlines so often about “superfoods” and which diets are the best for a long, healthy life. If you want your head to explode, do a search on “healthy diet.” Here are a few reasons why dietary studies are flawed:
- Self-reporting – the people in the study usually do not report what they ate and drank correctly.
- Large, randomized controlled trials are often not practical for studying diets as you need a test group that implements the diet and a control group that does not implement the diet. For a good study, the individual should not know if they are in the test group or the control group. Since “migraine diets” are often restrictive, it would not be possible to shield the participants from knowing which group they are in. Then, you have the question of whether or not the test group is following the diet as designed and that the control group is not making any changes to their diet.
- Diversity of food – During my last visit to the grocery store I counted 6 different varieties of apples and 5 varieties of potatoes. Which varieties are the test subjects eating? Histamine and tyramine are 2 important food components we look at for migraine and the content of these 2 substances varies greatly depending on the ripeness and freshness of foods. It may vary between the different varieties, too. How would it be practical to assure that people are eating foods that are the same ripeness and freshness?
- Diversity of people – we are all so different. How we digest, absorb and metabolize food can vary greatly. You need a lot of people to participate in studies in order to draw conclusions. Pardon the potty talk, but some of us flush down a lot more undigested food and nutrients than others.
- Funding – diet studies are often sponsored by food companies and industry groups with potential conflicts of interest. And, industries like the Onion Board (I just made that up) may not be interested in proving that raw onions are a big no-no for so many of us.
So, what about migraine? You’d think that with as often as people associate foods with migraine attacks that there would be at least a few studies to support more common culprits. Well, think again. There are few studies and the evidence is thin. What gives? For many of us, we are quite certain we are triggered by certain foods. Why don’t the few studies not support the existence of migraine triggers? The answer has to do with the Bucket Theory and reality of multiple triggers- food and non-food. If you have a migraine brain, your nervous system has abnormal reactions to normal stimulation. Your threshold to tolerate the stimulation is lower than the typical person without migraine.
The Bucket Theory
Ever wonder why you were able to get away with wine, pizza and chocolate on one day but not another? Has your doctor told you that those foods cannot be triggers because a real trigger would predictably result in a migraine attack each time? Maybe you took foods off of your “suspicious list” as your attacks are not consistent. Understanding the Bucket Theory is critically important to understanding the role of food triggers and how they relate to some of the other known migraine triggers like stress, sleep, hormones, lighting, noise, scents and hydration. Read more about it in this short but sweet blog on The Bucket Theory. In light of all the factors involved in reaching the migraine threshold, how can a study be designed to allow for that? Answer- it can’t.
It can be especially tricky to pinpoint which foods are problematic when you have frequent migraine attacks or chronic migraine or constant symptoms. The response to some triggers can be delayed. For instance, you might know that the scented candle is making you dizzy right away, but it may take a full day for your reaction to the yogurt cause symptoms. And, if we assume that you have 5 food triggers and enroll in a study with 19 other people with frequent attacks, things get more complicated. Each person may have a handful of different food triggers on top internal triggers (like hormones) or external migraine triggers (like perfume). How would such a study be designed? What if the study is testing foods high in tyramine while not considering low-tyramine foods that might be high in free glutamate or certain food additives? These issues vex researchers genuinely interested in getting good, hard data on food triggers.
What about migraine-oriented diets that aren’t based on triggers?
The research is thin in this area with the exception of the ketogenic diet. There are no good studies supporting diet changes that have helped many control their migraine attacks such as eating gluten-free, dairy-free, whole-foods or grain and sugar-free.
So, what to do given this lack of science to tout?
Do your own research and start your diet journey. If you started and stopped because you didn’t get relief, consider a different approach. There is no one “migraine diet,” but there is often better control to be discovered when you keep trying different approaches and combinations of medications and lifestyle tweaks. I’d love to have the science in my hand, but I’m not going to suffer while waiting for it when I think the evidence is already in front of me. Studies are usually started as researchers have a good hunch that an intervention works. We have more than a good hunch on diet and migraine.