YOU may be familiar with the signs. Flashes of light, a dull headache leading to severe pain, nausea and the urge to lie in a darkened room and sleep it away.

Some people never experience a migraine while others find their lives controlled by these agonising headaches.

Every sufferer will find their attacks triggered by something different but the most common causes are known as the five Cs: chocolate, coffee (and other sources of caffeine), cheese, claret (and other red wines) and citrus fruits.

Chocolate, coffee, cheese and wine contain chemicals that constrict and dilate the arteries while the acidity in citrus fruits, such as oranges, lemons and grapefruit, affects the delicate acid-alkaline balance in the body.

Dafydd Thomas, Professor of medicine at Imperial College London, says there appears to be a new C to add to the list: the contraceptive pill. “The pill can bring on migraines because of the oestrogen content. For the same reason women often experience a higher level of migraines at the start of their menstrual cycle due to the extra hormones present,” he says.

Other factors can also lead to an attack.

“People tend to get migraines at weekends when they sleep in late and their sleeping patterns are disrupted,” says Dr Thomas. “They often occur after periods of excitement. For example, many people get them on the first day of a holiday.”

Types of headache

In the UK migraines affect about 15 per cent of the population but they are twice as likely to occur in women than men. Those prone to migraines find their first attack occurs before the age of 30 and the frequency increases in their 40s and 50s.

Symptoms vary. Many people who suffer from bad headaches don’t know they have a migraine. They may just feel a bit off colour. Others can have alarming visual symptoms called auras. These consist of sequences of flashing lights and black spots.

Many people also experience vomiting and marked sensitivity to light. Migraines shouldn’t last for more than 24 hours. If they do it is important to see a GP as there could be something more seriously wrong.

Migraines are caused by chemical changes. Low levels of serotonin cause the blood vessels in the brain to spasm, become narrow and dilate.

There are generally two types of sufferers. Those who get migraines once a month or more and those who experience them only sporadically.

Discovering what prompts attacks can be laborious and Professor Thomas recommends asking a GP for a food-sensitivity test.

“When you get a migraine look back at what you consumed in the two days before. If you see any patterns emerging cut out those things from your diet for a while to see if your migraines lessen,” he advises.

Drinking plenty of fluids, remaining active and sticking to regular sleep patterns have been found to help prevent migraines.

It may be a case of trial and error but Professor Thomas says: “Learning what triggered your migraines is the first step to helping keep them at bay.”