If you've ever had a pulsating, throbbing headache for several hours or even a few days which was possibly accompanied by an upset stomach and sensitivity to light, you're probably familiar with migraines. Experts think migraines are caused by a chemical or electrical problem in certain parts of the brain. When your nervous system responds to a trigger, such as stress, spasms then occur in the nerve-rich areas at the base of the brain and constrict the blood vessels supplying blood to the brain. The migraine pain comes from other blood vessels that open up further to compensate for the constricted blood vessels. Pain also comes from the excitation of the nerve pathway that runs from the brain stem to the head and face.
Here are the nine most common triggers for migraines. If you can learn what your triggers are, you can learn ways to avoid them.