One in five Canadians suffers from migraine, a type of headache that results from inflammation of the blood vessels and nerves surrounding the brain. The exact causes of migraine headaches are not known but they seem to be set off by changes in brain activity. Very often, specific substances, actions or stimuli in your body or environment, may trigger migraines.
Research indicates that a migraine involves both the nerves and the blood vessels that feed the brain. Scientists have recorded a spreading pattern of electrical activity within the brains of people with migraines, which may be responsible for some of the classic migraine symptoms. Many people also experience a decrease in blood flow to various parts of the brain, again connected with the onset of migraine. More recently, there has been some evidence that serotonin, a powerful chemical that has the ability to constrict blood vessels, may help stimulate the migraine mechanism.
There are two common types of migraine and they each have slightly different symptoms:
Migraine with aura -- this is referred to as a classic migraine. The aura is a set of neurological symptoms that occur approximately 10 to 30 minutes before the headache starts. During the aura phase, you may experience visual disturbances, such as flashing lights or geometric patterns in front of your eyes or you may even suffer a brief vision loss. It is not uncommon to feel dizzy and confused or to have some facial tingling and muscle weakness as the aura progresses. Migraines with auras affect only 10 to 20 percent of migraine sufferers.
Migraine without aura -- this is known as a common migraine and it affects many more people than the classic migraine. People with this type of headache may have mood swings, feel depressed and fatigued or lose your appetite just before the migraine strikes.
The Canadian Headache Society has recommended a detailed set of criteria for assessing migraine symptoms. It is reasonable to assume you suffer from migraines if your headaches have some of the following characteristics:
- A sequence of at least five attacks that last between two and 72 hours
- Pain that is located on one side of your head, sometimes spreading to both sides
- Pain that is pulsating or throbbingPain that prohibits or limits daily activity
- Pain that is aggravated by physical activityNausea or vomiting during headache attacks
- Sensitivity to light, noise or smell during headache attack
Most migraines don't conform to a typical pattern. Some people only suffer a migraine once in a while and others are incapacitated by attacks that occur as often as three times a week. The intensity of pain can vary from reasonably mild to completely debilitating. Migraines also vary in length from a brief, 15-minute episode to an attack that can last a week. On average, the duration of a migraine ranges between two and 72 hours.
Who’s at risk?
Migraine is a universal condition that affects approximately six percent of men and 15 to18 percent of women. Although migraines can strike children and adolescents, they most often affect women between 25 and 55 years of age. As many as 50 to 70 percent of all migraine sufferers have a family history of the disease, indicating that these headaches may be hereditary.
In some cases, certain stimuli or 'triggers' may provoke migraines. Although triggers don't actually cause a migraine, they do seem to influence the activities in the brain that stimulate the disease. Often, migraine sufferers are sensitive to the combined effect of more than one trigger. There are many common migraine triggers and it is important to determine which ones affect you. Keeping a migraine headache diary is a good way to identify the circumstances that set off your migraines.
Diet. Certain foods and food additives are well known migraine triggers. Alcoholic beverages (especially red wine), foods treated with monosodium glutamate (MSG), foods that contain tyramine (aged cheeses, soy sauce) or aspartame (NutraSweet) and foods preserved with nitrates and nitrites all may provoke migraines. Chocolate, caffeine and dairy products are other known culprits.
Lifestyle. Changes in your behaviour or your surroundings can encourage migraines. If you alter your eating or sleeping habits, experience high levels of stress or smoke cigarettes, you may find yourself struggling with more frequent migraines.
Environment. Some people find that bright lights or loud noises will bring on a migraine. Weather or temperature changes and physical exertion are common triggers and even changing time zones may affect your headache frequency. Strong odours, perfume, high altitudes and computer screens are other recognized triggers.
Female hormones. Women may be more susceptible to migraines because of the estrogen cycles associated with menstruation. Migraines become more prevalent in females after puberty reaching a peak at age 40, and then declining in frequency as women age. But almost two-thirds of women who suffer migraines will experience a worsening of their headaches during their period.
Up to 15 percent of women will only get migraines during their period. Menstrual migraines are typically without aura and last longer than other migraines. They are also more difficult to treat.
To prevent them, it is extremely important for women to avoid migraine triggers during the premenstrual week. Oral contraceptives and estrogen therapy also seem to make migraines worse.
Migraines are more common in early pregnancy but usually improve by the second trimester. In a small group of women, pregnancy migraines will worsen throughout their pregnancies. During pregnancy, women should pay special attention to avoiding dietary and environmental triggers, sticking to a regular sleeping and eating schedules, getting regular exercise and managing stress (as should all women with migraines).
Dietary approaches to managing migraines
Identify and avoid food triggers. A number of foods have been reported to trigger a migraine attack. One study found that when people who suffer migraines eliminate these foods from their diet, about one-third experience fewer headaches, and up to 10 percent become headache free. The following is a list of the most common foods that can trigger a migraine, or make one worse:
- Coffee, tea
- Hot dogs
- Cheese, especially aged cheese
The following foods and food additives have also been reported to bring on a headache:
- Alcoholic beverages
- Artificial sweeteners
- Citrus fruits
- Foods with MSG
- Foods with nitrites/nitrates (processed meats, smoked fish, some imported cheeses, beets, celery, collards, eggplant, lettuce, radishes, spinach, turnip greens)
- Lima beans
- Overripe bananas
- Peanuts, peanut butter
- Red wine
Elimination and challenge diet. Some migraine sufferers have actual food allergies. It's believed that certain immune compounds formed in response to an offending food can trigger a migraine headache. If you find that certain foods are triggering migraines, it might be worthwhile to have your doctor refer you to an allergy specialist for food testing.
A dietitian who specializes in food sensitivities can plan an elimination/challenge diet for you, a useful tool used to identify food triggers. You can also do this on your own. Begin by keeping a food and headache diary. List all foods, beverages, medications and dietary supplements taken. Note the date of your menstrual period, since hormones may also precipitate a migraine. Keep this diary for at least two weeks or long enough to cover at least three migraine attacks. Once you've completed this exercise, look for patterns. Did you eat the same food before each migraine? Did your migraines hit you after a night of drinking wine?
Once you have identified possible culprits, eliminate them from your diet for a period of four weeks, or longer if you experience migraines less frequently. If you are migraine free during this period, it's very likely that you've found your triggers. The next step is to make sure these foods are the actual culprits. One by one test each food by adding it to your diet. Wait three days before testing the next food on your list. Keep in mind that this exercise may not give you clear cut results. A combination of events may be required to bring on a migraine. For instance, you may only get a migraine when you eat the food at a specific time in your menstrual cycle. Or, the combination of stress and a food trigger may be required to cause a migraine.
Vitamins and Minerals
Vitamin B2 (Riboflavin). Riboflavin is needed to facilitate the release of energy from all body cells. In fact, studies reveal that migraine sufferers have less efficient energy metabolism in their brain cells. It's thought that by increasing riboflavin intake and therefore the potential of brain cells to generate energy, migraines might be prevented. In a well-controlled study conducted among 55 patients with migraine, a daily 400-milligram supplement of this B vitamin reduced the frequency of headache attacks in a manner similar to certain drugs used for this condition.
The recommended dietary allowance for riboflavin is 1.1 to 1.3 milligrams per day. Riboflavin is found in many foods including milk, meat, eggs, nuts, enriched flour and green vegetables. If you take a multivitamin or B complex supplement you're getting even more riboflavin, as much as 100 milligrams.
To prevent a migraine, take 400 milligrams of B2 once daily. B2 supplements are available in 25, 500, 100, 500 and 1200-milligram doses. It may make take up to three months to notice an improvement in your headache frequency. Riboflavin supplements are non-toxic and very well tolerated.
Magnesium. Evidence shows that up to 50 percent of people during a migraine headache have low magnesium levels in their brain and red blood cells. It's thought that a deficiency of magnesium in the brain can cause nerve cells to be overly excited, triggering a migraine attack. (A few medications can deplete magnesium stores including estrogen, estrogen-containing birth control pills, and certain diuretics.)
Researchers from Germany gave 81 migraine sufferers either 600 milligrams of magnesium or a placebo pill once daily for three months. In the second month of the study, the frequency of migraine attacks was reduced to 42 percent in the magnesium group, compared to only 16 percent in the placebo group. The duration of a migraine and drug use significantly decreased among those people who took magnesium supplements.
The best sources of magnesium are whole foods including unrefined grains, Nuts, seeds, legumes, prunes, figs, whole grains, leafy green vegetables, Brewer's yeast, cheddar cheese, shrimp.
To prevent a migraine, take 600 milligrams of magnesium per day, in divided doses. Buy a magnesium citrate supplement as the body absorbs this form more readily. Taking more than 350 milligrams of supplemental magnesium per day may cause diarrhea.
Feverfew. The link between feverfew and migraine became popular in England back in the 1970s when a doctor's wife noticed that her migraines were much improved once she started chewing fresh feverfew leaves. As the story goes, after one year of faithfully taking the leaves, she almost forgot that she ever suffered from migraines.
Since then, this herbal remedy has been the focus of a number of studies in people with migraines. In one study, 76 people who experienced migraines were given either whole feverfew leaf or placebo for four months and then the treatments were reversed for another four-month period. Without knowing what treatment they received, 59 percent of the people taking feverfew identified the feverfew period as more effective, compared to 24 percent who chose the placebo period. Feverfew reduced the number of classic migraines by 32 percent and common migraines by 21 percent.
Feverfew is thought to reduce the frequency and intensity of migraines by preventing the release of substances, called prostaglandins, which dilate blood vessels and cause inflammation.
The recommended dose is 80 to 100 milligrams daily of powdered feverfew leaf. Buy capsules of powdered feverfew leaf. You can also try taking the herb at the onset of a migraine to ease the symptoms.
Feverfew rarely causes side effects other than mild gastrointestinal upset. The herb may cause an allergic reaction to people sensitive to members of the Asteracease/Compositae plant family: ragweed, daisy, marigold, and chrysanthemums.
The Migraine Association of Canada
National Headache Foundation
American Council for Headache Education
The above is an excerpt from "Leslie Beck's Nutrition Encyclopedia" (Penguin Canada, 2001/2003), available at bookstores across the country. The following is copyrighted and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or means - electronic, mechanical, photocopying, or likewise.
All research on this web site is the property of Leslie Beck Nutrition Consulting Inc. and is protected by copyright. Keep in mind that research on these matters continues daily and is subject to change. The information presented is not intended as a substitute for medical treatment. It is intended to provide ongoing support of your healthy lifestyle practices.