What are migraine triggers?

A migraine trigger is any environmental or physiological factor that leads to a headache in individuals who are prone to develop headaches. Only a small proportion of migraine sufferers, however, clearly can identify triggers. Examples of triggers include:

• stress,
• sleep disturbances,
• fasting,
• hormones,
• bright or flickering lights,
• odors,
• cigarette smoke,
• alcohol,
• aged cheeses,
• chocolate,
• monosodium glutamate,
• nitrites,
• aspartame, and
• caffeine.

For some women, the decline in the blood level of estrogen during the onset of menstruation is a trigger for migraine headaches (sometimes referred to as menstrual migraines).

The interval between exposure to a trigger and the onset of headache varies from hours to two days. Exposure to a trigger does not always lead to a headache. Conversely, avoidance of triggers cannot completely prevent headaches. Different migraine sufferers respond to different triggers, and any one trigger will not induce a headache in every person who has migraine headaches.

Sleep and migraine

Disturbances such as sleep deprivation, too much sleep, poor quality of sleep, and frequent awakening at night are associated with both migraine and tension headaches, whereas improved sleep habits have been shown to reduce the frequency of migraine headaches. Sleep also has been reported to shorten the duration of migraine headaches.

Fasting and migraine

Fasting possibly may precipitate migraine headaches by causing the release of stress-related hormones and lowering blood sugar. Therefore, migraine sufferers should avoid prolonged fasting.

Bright lights and migraine

Bright lights and other high intensity visual stimuli can cause headaches in healthy subjects as well as patients with migraine headaches, but migraine people who suffer from migraines seem to have a lower than normal threshold for light-induced headache pain. Sunlight, television, and flashing lights all have been reported to precipitate migraine headaches.

Caffeine and migraine

Caffeine is contained in many food products (cola, tea, chocolates, coffee) and OTC analgesics. Caffeine in low doses can increase alertness and energy, but caffeine in high doses can cause insomnia, irritability, anxiety, and headaches. The over-use of caffeine-containing analgesics causes rebound headaches. Furthermore, individuals who consume high levels of caffeine regularly are more prone to develop withdrawal headaches when caffeine is stopped abruptly.