Most people experience a headache from time to time. But for people who suffer from migraine headaches, the pain can be debilitating, causing missed work days and lost productivity.
It's estimated that as many as four million Canadian adults live with migraines, with women suffering more often than men.
While changing your diet can't cure migraines, certain foods and dietary habits can trigger pain. Knowing what these are - and if they affect you - can help prevent a future attack.
Migraine is a chronic condition of recurrent attacks that last from four to 72 hours. The headache is often described as severe pulsing or throbbing pain felt on one side of the head, although some migraines occur on both sides. Migraines are often accompanied by nausea, vomiting and sensitivity to light and sound.
Up to 60 per cent of migraines are preceded by warning signs such as sleepiness, irritability, depression or food cravings. Fewer are associated with an aura occurring 10 to 30 minutes before the headache, such as bright flashing lights or a blind spot in one's field of vision. For some migraine sufferers, auras include audio hallucinations and abnormal tastes and smells.
Migraines are caused by swollen blood vessels and the release of chemicals from nerve fibres that cause inflammation, pain and further enlargement of blood vessels.
A migraine trigger is anything that that can lead to a headache, or its symptoms such as nausea or and sensitivity to light. These vary from person to person, and from migraine to migraine in the same person. Often it's not just one trigger that provokes an attack, but the combined effects of a few.
While some triggers can't be controlled - the weather, seeing bright lights, female hormones - others can be managed.
Certain foods, being overweight, stress, lack of sleep and changes in daily routine or environment can set off a migraine or worsen the pain by influencing brain chemicals or stimulating areas of the brain.
When it comes to diet, the most common triggers include chocolate, cheese, citrus fruit and alcohol, especially red wine. Tyramine, a natural chemical found in pickled and fermented foods, is thought to precipitate a migraine. Tyramine-rich foods include aged cheese, sour cream, yogurt, smoked or cured meat and fish, red wine, beer, yeast, teriyaki sauce, soy sauce, miso and tempeh. Brazil nuts, peanuts, avocados, bananas, raspberries and raisins also contain tyramine.
Foods that contain monosodium glutamine (MSG), such as commercial soups, soy sauce, salad dressings and frozen dinners, have also been linked to migraines. Aspartame, an artificial sweetener found in many diet drinks and foods, has also been reported to trigger migraines in some people.
Another possible culprit: preservatives called nitrates and nitrites added to deli meats, hot dogs, sausages and bacon.
It's not just what you eat that may be to blame: Getting too little sleep, not exercising, and letting stress get the best of you are also known migraine triggers.
If you think your diet or other lifestyle habits may be worsening your migraine, the following strategies may help manage your headaches.
Keep a food and headache diary
This might sound tedious, but keeping a diary can help you identify factors that lead to migraines. Document your symptoms, headache frequency and duration, and any potential triggers such as diet, activities, weather conditions, stress and changes in sleep habits.
Share this diary with your doctor to help identify patterns to your migraines. It may take a few months before you can identify your triggers.
High doses of caffeine can cause headaches. Limit your intake to no more than 200 milligrams per day - the amount in roughly 12 ounces of regular coffee. Consider caffeine from all sources: soft drinks, tea, energy drinks and chocolate.
If you consume caffeine regularly, don't go cold turkey. Abruptly stopping caffeine can cause withdrawal headaches. Gradually cut back over two to three weeks.
Don't skip meals
Fasting or going for a prolonged period of time without eating can cause a migraine. Eat three balanced meals and one or two midday snacks to help balance your blood sugar and brain-chemical levels.
It's thought that a deficiency of magnesium in the brain can cause nerve cells to be over excited, triggering a migraine attack. Some studies have shown that taking a magnesium supplement can reduce migraine frequency.
The best sources of magnesium include whole grains, nuts, seeds, legumes, dried fruits and leafy green vegetables. Before supplementing, speak to your health-care provider. Talking more than 350 milligrams of magnesium can cause stomach upset.
This B vitamin facilitates the release of energy from all cells in the body, including brain cells. Two well-controlled studies found that a daily 400-milligram supplement of riboflavin was effective at reducing the frequency of headaches.
It may take up to three months to notice an improvement in headache frequency. Riboflavin supplements are non-toxic and very well tolerated.
Stick to a sleep schedule
Evidence strongly suggests that good sleep habits can cut migraines. In a study of 43 female migraine patients, those who were told to schedule eight hours of sleep each night, not to read or watch television in bed, to limit their fluid intake two hours before bed, and eat dinner four hours before, significantly reduced migraine frequency. (No one in the control group reported fewer migraines.) Headache experts advise going to bed and waking up at the same time each day. Adults should aim for seven to eight hours of sleep each night; children and teenagers need nine to 10 hours.
Get regular exercise
Physical activity can improve sleep, help blow off stress and reduce the frequency and severity of migraines. Aim to be active most days of the week - even when travelling. If you're not used to exercise, take it slowly. Overexertion may provoke a migraine.
Manage your weight
Studies have revealed that adults and children who are overweight have more frequent - and more disabling- headaches than their leaner peers. Exactly why is not known, but a lack of exercise and poor sleep habits may be involved. (Obesity often leads to poor sleep.)
Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. Her website is lesliebeck.com.