What causes a migraine is not fully understood. Scientists do know that a series of events occur in the brain and the result is migraine pain. People with migraines report a variety of factors that are associated with their headaches. These factors are called triggers. For people with migraines, avoiding triggers may be the only way to avoid a migraine.

Each person’s triggers will be different. Some people who have migraines may never discover a reliable trigger, while others may have multiple triggers. Read on to learn about the different triggers that are known to cause migraines.

The most common triggers

Causes

The most common triggers for migraines include:

Foods

The most common food offenders include aspartame, an artificial sugar substitute; foods that contain tyramine (a substance that forms as foods age), such as aged cheeses, hard sausages, and Chianti wine; foods that contain monosodium glutamate or MSG, a key ingredient in many broths, Asian foods, and processed foods; caffeinated or alcohol drinks, particularly beer and red wine; and foods that contain nitrates, such as hot dogs, bacon, and salami. Skipping a meal, fasting, and becoming dehydrated may also increase your likelihood for a migraine. For many, tree nuts are also a common food trigger.

Hormonal changes

Hormones are a particularly troublesome trigger for many women—fluctuations in estrogen and progesterone caused by birth control, menstruation, pregnancy, or menopause, may cause a migraine. Hormone replacement therapy can trigger or even worsen migraines, too.

Physical activity

Physically exerting yourself—whether through exercise, sexual activity, or physical labor—may cause a migraine. Notify your doctor right away if physical activity always brings on a headache, as this can be a sign of a more serious health condition beyond migraine

Medications

Certain medications may increase the frequency of migraines. These can include oral contraceptives, blood pressure medications, vasodilators and medications used to treat depression and anxiety. Interestingly, some of these same medications can also make migraines better.

Genes

Research suggests your genetics may play a role in who is likely to suffer from migraines. According to the National Headache Foundation, 70-80 percent of people with migraines have a family history of severe headaches. If your parents or siblings have migraines, you’re more likely to have them as well.

Gender

Migraines disproportionately affect women. However, in childhood, boys are more often affected than girls. The gender switch begins around the time of puberty.

Age

Most people will experience their first migraine in adolescence, but they can occur at any age.

Weight

Women who are obese or mildly obese have a greater risk for migraine headaches than women with a lower BMI.

Other known triggers:

  • getting too much or too little sleep
  • emotional or mental stress and anxiety
  • bright lights
  • loud noises
  • strong odors, such as perfumes or secondhand cigarette smoke
  • changes in the weather and barometric pressure

How you can find your triggers

Write and edit

You can pinpoint your migraine triggers by keeping a headache diary. Each time you have a migraine headache, record it. Note any symptoms that occur before, during, and after the headache. Be sure to record the time of day your headache started; what you ate or drank in the 24 hours preceding the migraine; where you were and what you were doing when the symptoms of the migraine began; and, finally, if you had any other conditions that might have triggered the migraine such as lack of sleep, illness, excessive stress, or allergies. If you’re a woman not in menopause, note when the headache occurred in relation to your menstrual cycle.

Make sure your doctor knows what medications you take for other health problems on a regular basis, along with any vitamins or supplements. If you take any medications for your migraine, record what and how much you took. Also note if that medication helped and how quickly it helped. If your doctor has prescribed a medication to treat your migraines, having a record of its effect on your headache will be especially helpful for him or her to determine if you’re taking the right medicine and dose.

Take this journal with you to your next doctor’s appointment. Having your doctor review your headache journal may help your doctor pinpoint possible triggers. Start by avoiding those suspected triggers as best you can in order to prevent another migraine. If a migraine occurs anyway, record that information and share it with your doctor. If you find that avoiding specific things makes it less likely you’ll get a headache, you’ve found the triggers for your headaches, and avoiding them from now on will typically decrease the number of migraines you have.

Avoiding triggers

Prevention

You can’t always avoid what causes your migraines, but for those triggers you can control, avoiding them may help you prevent migraines or at least lessen their frequency. Keep away from any food or drinks that make headaches worse. If you know a particular perfume or scent brings on a migraine, also avoid that. If possible, establish a daily routine and set up environments, both at home and work, that are less likely to initiate a migraine headache for you.