Migraine Headache Causes

The cause of migraine headaches is not fully understood. It was once thought that migraines were due to expanding and constricting blood vessels on the surface of the brain. Today, scientists believe that migraines are caused by inherited functional changes in a person's cranial nerves (nerves that originate in the brain). The functional changes typically occur when people are exposed to certain triggers (such as food, stress, or bright light).

The following changes cause the pain experienced during a migraine headache:

• A decrease in the level of serotonin, an organic compound that constricts (narrows) blood vessels.
• The cranial nerves respond by releasing neuropeptides, organic compounds that influence nerve activity.
  
• The blood vessels in the brain become dilated (enlarged) and inflamed.

Migraine predisposition

Migraines can run in families. If one parent gets migraines, a child has a 50% chance of developing migraines. If both parents get migraines, a child has a 70% chance of developing migraines. Migraines also occur more often in Caucasians than in African Americans or Asian Americans.

Although not all migraine cases may be due to genetics, several genes that predispose people to developing migraines have been identified, such as the genes that cause migraines with aura and migraines without aura.

People are more likely to get migraines between the ages of 10 and 46. Although children of both sexes are equally likely to get migraines, this changes when females start menstruating. Adolescent and adult females are three times more likely to get migraines than men.

Migraine triggers

There are numerous triggers that can bring on a migraine. People react to different triggers and many people react to more than one trigger. Over time, people can usually identify which triggers (or trigger combinations) are likely to cause them to have a migraine attack.

Typical migraine headache triggers include:

Emotional and physical triggers

• Changes in sleep patterns
• Mental stress
• Physical exertion

Environmental triggers

• Allergic reactions
• Altitude changes
• Bright light or glare
  
• Certain odors and perfumes
• Loud noises
• Seasonal, time zone, or weather changes
• Smog and smoke
• Smoking and second-hand smoke

Food triggers

• Amino acid tyramine containing foods, such as aged and cultured cheese, beer, chicken liver, figs, red wine, smoked fish, some beans, and yeast
• Baked breads
• Caffeine
• Chocolate
• Dairy products
• Fruits, such as avocado, banana, and citrus fruit
• Nuts and peanut butter
• Onions
• Meats containing nitrates, such as bacon, hot dogs, salami, and cured meat
• MSG or monosodium glutamate containing foods, such as soy sauce, meat tenderizers, and seasoned salt
• Processed, fermented, pickled, or marinated foods
• Skipping meals

Hormonal triggers

• Contraceptives
• Hormone replacement therapy
• Menstrual cycles (Females are more likely to get migraines when menstruating, when pregnant, and during menopause.)

Medication triggers

• Blood pressure medications
• Contraceptives and hormone replacement therapy
• Nitroglycerine preparations
• Overuse of pain medications, such as aspirin products containing caffeine, ibuprofen (brand name: Advil, Motrin), naproxen (Aleve), or indomethacin (Indocin)