KEEP warm - it could stop you getting a stroke.

That was the warning today from The Stroke Association, the national charity dedicated to combating the condition.

The charity has put out its plea as the country was plunged into icy temperatures this week.

Sue Wayne, training and development manager for the association, said: "A drop in room temperature can lead to a drop in the body's core temperature below 37 degrees celsius.

"This can cause contraction of blood vessels and thickening of the blood.

"Together, this makes the heart work faster and raises blood pressure - high blood pressure is the single biggest risk factor for stroke.

"Low core body temperature also makes the blood more likely to clot, which can cause an ischemic stroke."

Dr David Fair, a GP at Jorvik Medical Practice, said it was important for a person's general health to keep warm when it was cold outside.

"Older people are at risk of developing hypothermia because they tend to have a slower metabolism," he said. "They tend to lose the sensation of getting cold."

He advised people to make sure at least one room in their home was well heated.

"Have several layers of clothing on, stay in bed if it's very, very cold, and don't be shy of using your winter heating allowance - that's what it's there for," he said.

James Player, deputy chief officer of Age Concern York, said: "It's very important that older people don't neglect themselves - they must keep warm whatever the circumstances and follow the advice of their doctors and consultants."

The Stroke Association's tips to stay warm this winter include keeping the home at the right temperature - it recommends between 21C and 24C. Regular hot drinks are also beneficial, and hats and gloves should be worn outside.

According to the association, strokes are the UK's third biggest killer, and the leading cause of adult disability.

Every year, about 150,000 in Britain have a stroke, of which about a third are likely to die within ten days, and another third will probably be left disabled.

A stroke happens when the blood supply to the brain is disrupted. Most occur when a blood clot blocks the flow of blood to the brain, while some are caused by a burst blood vessel in the brain area. The Department of Health's Home Heat Helpline is on 0800 33 66 99.