Migraine is one of the common problems that afflict many of the people. This headache problem occurs due to changes in the brain and the blood vessels surrounding them and lasts from 4 hours to three days. The frequency of these headaches vary from a daily basis to less than once a year. National Headache Foundation, a research organization dedicated to health issues in the United States of America has found out that around 37 million people in the United States have issues related to a migraine. Causes of migraine headaches The exact causes of migraine headaches are yet not known, but it is believed that it occurs due to the expansion of the blood vessels and release of some chemicals which results in the occurrence of pain. It is, however, known that different triggers ignite a migraine and different people have distinct triggers, which incite a migraine in them. Foods such as cheese, nuts, chocolate are the causes of migraine headaches in some people. If a person misses the meal, it can also result in a headache which eventually transforms into a migraine. Stress are some other causes of migraine headaches. Increased emotional and physical stress also causes migraine headaches in some people. Symptoms of a migraine The symptoms of a migraine also vary with people. Five distinct phases of a migraine are known now. Prodrome A migraine has many pre-warnings before it occurs. Change in mood, change in sensations, fatigue and muscle tension are some of the warnings which indicate that a migraine is about to occur. Aura This is kind of sensory disturbance which precedes a headache. Some people see blind spots and feel as if geometric patterns and colorful lights are visible. In serious cases, people who suffer from a migraine might lose vision in one eye.