Food-related triggers occur in about 10-20% of people with migraine. Many people will crave snack food such as chocolate or chips in the early stages of a migraine attack, leading them to conclude that particular food is a trigger. However, if the craving for a specific food is a symptom of the beginning of the attack, it probably is not a trigger, and you need to find out what you did or ate before that.
Some food products contain chemicals or additives, which may also be implicated in an attack. Ones that people with migraine frequently mention are monosodium glutamate, nitrates and aspartame. Tyramine is a chemical found in red wine and soft cheeses like camembert and brie that is often indicated as a migraine trigger.
If you think you have food triggers, particularly the more difficult to identify chemicals or additives, you are best to do a full elimination diet with the help of a dietician (you can get access to a dietician under Medicare through your GP with a chronic condition health care plan, and there are also dieticians in the public health system you may be able to access). The RPAH Allergy Clinic in Sydney, which developed the elimination diet, has the handbook and recipe books you can buy and some basic information available on their website. Note: an elimination diet is a diagnostic tool to find your triggers, not an eating plan to avoid migraine attacks. Living on an elimination diet will mean you are not getting enough nutrients.
Missing meals or insufficient food is one of the most significant dietary triggers for migraine attack. Try eating 5-6 small meals a day or having healthy snacks between meals. If you are vomiting a lot or unable to eat during a significant attack, it is ok to keep the blood sugar up with a soft drink or whatever you are craving. Try not to make that an everyday occurrence.
There are many diets sold to people living with migraine. While some may be based in science, most are just selling yet another miracle cure to those in our community desperate to try anything. Of course, if you want to try a diet, you should do so, but avoid diets or programs with any level of fasting that eliminate carbohydrates (low carb is fine) or that have any expensive supplements or meal replacements.
Many people are confused by food triggers because they eat something one day and they are fine, and another day it sets them off. Migraine is like that, unfortunately, because it is actually a combination of many sensory inputs that leads to an overload once you have passed the threshold of what your brain can handle.
One thing many people don't think about is how fresh your food is. If you are intolerant to some foods or mould, eating leftovers, slightly stale bread, or fruits and vegetables that are very ripe may be enough. As foods age, they break down and create higher levels of food chemicals. That makes them taste really good, but it's also a bigger sensory overload for your brain. Try eating food the day you get from the supermarket, and choosing fruits and vegetables that are a little less ripe, and see if it helps.