How do cold weather health alerts work?
What does cold weather do to the body?
Flu and certain other diseases that cause colds and sore throats spread more easily in the winter months. Pneumonia, when there is inflammation in the lungs because of an infection, is more common after cold weather.
Cases of norovirus - the winter vomiting bug - tend to rise too.
Prof Damian Bailey, from the University of South Wales, made a programme for BBC Radio 4's Inside Health about the effects of cold on the body.
Presenter James Gallagher spent 30 minutes in a room where the air temperature dropped from 21C to 10C.
During the experiment, the blood flow to his brain fell, his blood pressure and heart rate increased, the temperature of his extremities - arms, legs and head - dropped, and he took significantly longer to complete a series of puzzles.
Prof Bailey said 18C is the body's tipping point - below that and the body has to work hard to maintain its core temperature. That is one reason why heart attacks and strokes are more common in the winter months.
Flu and certain other diseases that cause colds and sore throats spread more easily in the winter months. Pneumonia, when there is inflammation in the lungs because of an infection, is more common after cold weather.
Cases of norovirus - the winter vomiting bug - tend to rise too.
Prof Damian Bailey, from the University of South Wales, made a programme for BBC Radio 4's Inside Health about the effects of cold on the body.
Presenter James Gallagher spent 30 minutes in a room where the air temperature dropped from 21C to 10C.
During the experiment, the blood flow to his brain fell, his blood pressure and heart rate increased, the temperature of his extremities - arms, legs and head - dropped, and he took significantly longer to complete a series of puzzles.
Prof Bailey said 18C is the body's tipping point - below that and the body has to work hard to maintain its core temperature. That is one reason why heart attacks and strokes are more common in the winter months.
When it is not possible to keep rooms heated to 18C, he recommends wearing gloves, warm socks and a woolly hat, eating a higher carbohydrate diet and generating more body heat by moving around.