Asked by: Rachel Carmichael, Leicester
Amazingly, the precise cause of migraines is still unknown. These intense headaches, often on one side and accompanied by nausea and sometimes visions of zigzag lines and extreme sensitivity to light and noise, must be caused by abnormal brain activity. But we just don’t know what kind or whether there are many different causes.
Hormonal fluctuations, especially in oestrogen, can trigger migraines. So some women suffer more during menstruation, pregnancy or menopause. Certain foods and additives can cause migraines and people who diet, skip meals or consume a lot of caffeine can suffer. Disturbed sleep and jetlag can also cause them.
One rare inherited type called familial hemiplegic migraine is caused by four specific gene mutations. More common types are also associated with many different genes that affect brain function. The simplest answer lies in the family. Up to 90 per cent of sufferers have a family history of migraines.
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