Migraine headaches affect about 6 out of 100 people. They are a common type of chronic headache. They most commonly occur in women and usually begin between the ages of 10 and 46. In some cases, they appear to run in families.

Migraines occur when blood vessels of the head and neck spasm or constrict, which decreases blood flow to the brain. Minutes to hours later, the blood vessels dilate (enlarge), resulting in a severe headache. Inflammation around the blood vessels also occurs in some cases.

Common migraine accounts for almost all migraine headaches. Common migraine may be accompanied by symptoms other than headache but only rarely includes any preceeding symptoms (aura). Migraine may also appear as classic migraine (a migraine preceded by other symptoms) and other rare forms.

Multiple mechanisms trigger the spasm and subsequent blood vessel dilation. Attacks of migraine headache may be associated with:

• Allergic reactions
• Bright lights and loud noises
• Relaxation after a period of physical or mental stress
• Prolonged muscle tension (or tension headache)
• Lack of sleep
• Smoking or exposure to tobacco smoke
• Missed meals
• Specific foods
• Alcohol use and caffeine,
• Menstrual periods
• Use of oral contraceptives (birth control pills)
• Other conditions

Foods that have been associated with migraine in some people include foods containing the amino acid tyramine (red wine, aged cheese, smoked fish, chicken livers, figs, some beans), chocolates, nuts, peanut butter, fruits (avocado, banana, citrus fruit), onions, dairy products, baked goods, meats containing nitrates (bacon, hot dogs, salami, cured meats), foods containing monosodium glutamate (an additive in many foods), and any processed, fermented, pickled or marinated foods.