The exact cause of a migraine is not fully understood, but doctors and healthcare providers do know that many factors can induce a migraine. If you’re one of the millions of people who deal with frequent or occasional migraines, it’s important to understand your personal migraine triggers and do your best to avoid them. Keeping a journal of known triggers—such as certain foods, sounds, or bright lights—may be beneficial in avoiding future migraine attacks. It’s also crucial to never overuse or abuse any prescription treatment for a migraine. Misuse of medication can lead to increased migraine attacks and chronic migraine symptoms.

Stress

A dramatic increase or decrease in physical or psychological stress can trigger a migraine. Danish researchers found that a majority of migraine patients report that stress is linked to the onset of migraine attacks. Other researchers have reported that between 50 and 80 percent of migraine patients say stress triggers their migraine headaches. Some patients experienced a migraine in the aftermath of a stressful event, while others experienced a new attack in the midst of a stressful event.

Lack of Sleep or Jet Lag

Sleep disturbance is one of the most common factors linked to a migraine. Insufficient sleep is often cited as a trigger for acute migraine attacks. Excessive sleep is a frequently reported trigger as well. Jet lag and changes in your work schedule can also be linked to the onset of a migraine. Insomnia is the most common sleep disorder associated with chronic migraines. Chronic migraine patients who suffer from insomnia are at increased risk for anxiety or depression. These conditions have one thing in common: sleep disturbance. Fortunately, many patients report that sleep often relieves their migraine headaches.

Food Additives

The artificial sweetener aspartame and the flavor enhancer monosodium glutamate (MSG) may trigger a migraine. Experiments with aspartame have yielded conflicting results. The issue of its possible effects among migraine patients remains unresolved. There is some evidence that clinical depression patients may experience worsened symptoms after consuming aspartame. MSG is a “flavor enhancer.” It is used to impart a savory flavor to various foods. Many people in the general public believe MSG can trigger headaches. Most controlled research has failed to identify a link between the consumption of MSG and headache, or any other condition, in normal individuals. However, a recent study concluded that MSG could trigger a headache and pain in the face and head. It may be wise to avoid this additive.

Hunger or Dehydration

Migraine patients would do well to avoid skipping meals. Research consistently shows that skipping meals is frequently linked to the onset of a migraine. It remains uncertain how this happens. It is probably related to falling blood glucose levels. Dehydration has also been suggested as a possible migraine trigger. Failure to drink enough water has been linked to the onset of a headache. A small survey of migraine sufferers revealed that “insufficient fluid intake” was linked to headache onset in about 40 percent of responders.

Highly Caffeinated Beverages

Some experts have reported that excessive caffeine consumption may trigger a migraine. That’s why it’s wise to monitor your intake of caffeine from coffee, tea, soft drinks, and energy drinks. Caffeine levels can be surprisingly high in energy drinks. Some researchers have noted that caffeine withdrawal may also trigger a headache. Other experts warn against the over-consumption of caffeine. Keep in mind that many over-the-counter headache preparations contain significant amounts of caffeine. One recent controlled study concluded that a drug combining acetaminophen, aspirin, and caffeine was better at relieving the symptoms of a migraine headache than ibuprofen alone.

Medication Overuse

Overuse of medications is one of the most common factors in migraines. Specifically, people who overuse common analgesics can be more likely to progress from occasional migraines to chronic migraines. Overuse may lead to more frequent headaches, and possibly greater pain as well. It’s unclear why taking too many analgesics may actually make migraine symptoms worse. But, it’s evident that so-called analgesic rebound headaches need to be addressed when treating migraines. Additionally, overuse of drugs in the opioid class is especially likely to be associated with the development of chronic migraine.

Alcohol

One of the most commonly reported triggers for migraines is alcohol. Alcohol triggered a migraine in about one-third of migraine patients in a recent Brazilian study. Red wine appears to be somewhat more likely to trigger a migraine than other sources of alcohol, especially among women. In the study, red wine triggered a migraine in 19.5 percent of male and female migraine patients. White wine was associated with a migraine in just 10.5 percent of patients. A closer look at the study’s numbers shows that red wine disproportionately affects women. Red wine triggered a migraine in just eight percent of men, but among women, the number jumped to 22 percent.

Odd or Strong Smells

Migraine patients frequently report that strong or unusual smells trigger their headaches. They often cite perfume, in particular, as a trigger. Additionally, about half of migraine patients report an intolerance for smells during attacks. This phenomenon is known as “osmophobia” and is unique to migraine headache sufferers. During migraine episodes, affected patients said cigarette smoke, food smells, and scents (including perfume) were most frequently offensive. One recent study concluded that migraine patients with osmophobia were more likely to exhibit symptoms of anxiety and depression.

Bright Lights and Loud Sounds

Some patients report that bright, flickering, or pulsating lights, or loud sounds, may serve as a migraine trigger. Even brief exposure to sunlight may trigger a migraine in some patients. A recent article in European Neurology noted, however, that sunlight may not be a primary trigger. It may trigger a migraine only after the patient drank wine the previous night. Alternately, the patient may already be sleep-deprived, stressed, dehydrated, or experiencing low blood sugar due to skipping a meal. Bright light may be a sort of secondary trigger. People whose migraine attacks appear to be triggered by bright light should consider whether these other factors were triggers. Other researchers report that sunlight alone may trigger a migraine. Patients reported getting some relief by wearing a hat, wearing sunglasses, avoiding sunny places, or getting more sleep.

Medications

People with migraines often overuse certain medications, such as opioids and butalbital. Overuse of these and other pain-relieving medications, such as over-the-counter NSAIDs, may actually cause headaches to occur more frequently. It’s unclear why this is. Discontinuing offensive medications may be necessary before it is possible to gain control over migraine symptoms.

Changes in Weather

Various weather changes have been tentatively linked to the onset of a migraine headache. In a recent Brazilian study of teens with a migraine, weather patterns most likely to trigger a headache included sunny and clear, hot, cold, and changing weather. Another recent study, featuring mostly women from the American Midwest, concluded that thunderstorms with lightning were significantly linked to the onset of a headache. Specifically, investigators concluded that lightning was the precipitating factor, although they were uncertain how lightning might trigger a migraine.

Hormones

Women are three times more likely to suffer from a migraine headache than men. Evidence suggests that female sex hormone fluctuations may play a role in headache onset and severity. More than half of female migraine patients in a recent study said they were likely to get severe migraine headaches during menstruation. A small subset of these patients experienced a migraine solely during menstruation. The use of oral contraceptives may make symptoms worse, while pregnancy may offer relief to some migraine patients. Pregnancy was linked to worsening symptoms for other patients. Post-menopause may provide some limited relief from headache severity.

Physical Activity

Intense exercise may trigger migraines. A recent study found that 38 percent of migraine sufferers experience exercise-triggered migraine attacks at some point. Many patients with exercise-induced migraines report that their headaches begin with neck pain. More than half abandoned a favorite sport or form of exercise in an effort to avoid triggering migraine attacks. Some patients report that they’ve been able to substitute low-intensity exercises for high-intensity activities that might trigger an attack.

Foods

Certain foods, or the lack of food (fasting), are frequently reported as possible triggers for a migraine attack. The number of patients who say that certain foods trigger migraine headaches ranges from 12 percent to 60 percent. A 2008 Brazilian study found that most patients reported having at least one migraine trigger. Diet was one of the most frequently reported triggers. Fasting was the most common diet-related trigger reported. Alcohol, chocolate, and caffeine were the most common substances associated with a migraine attack. In the Brazilian study, red wine was a frequent trigger among women but not men. Other foods frequently associated with migraine include cheese, salami, chocolate, and artificial sweetener aspartame.