天冷会影响我们的身体。寒冷的天气会对我们造成哪些影响？在什么温度下，它会开始影响我们的身体？

When we think of low temperature as a danger, we often imagine people working outside in polar regions in the depths of winter or in cold storage facilities, layered in thermal clothing to help them deal with freezing temperatures. But do we also need to protect ourselves when it's just a bit chilly as well as in arctic conditions?

As mammals, our bodies have to maintain an internal temperature in a narrow range between 37 and 37.5C. If that temperature drops, the effects can be serious. Below 35C, people can develop hypothermia, with symptoms such as shivering, confusion, and slurred speech. If body temperature drops below 29C, it can lead to loss of consciousness. Fortunately our bodies can regulate their internal temperature, but there are some negative side effects which come with this process.

Ten degrees Celsius is hardly biting cold, but that's the temperature that BBC journalist James Gallagher was made to endure in an experiment at the University of South Wales. As the test room was cooled from 21 degrees, his blood pressure, heart rate and breathing rate all increased, while the flow of blood to his brain decreased by 20%. What are the consequences of this? Immediately, it meant that Gallagher took longer to solve some simple puzzles. As a longer-term risk, Professor Damian Bailey points out that increased blood pressure puts us at greater risk of stroke and heart attacks.

Professor Bailey suggests that in the cold, people should wear clothing that provides good insulation, eat more carbohydrates, and be more active. Another approach is suggested by Professor Christopher Minson. He believes that people are too reliant on being able to control the temperature around them, and that we can gradually train ourselves to cope with a lack of warmth and be comfortable at lower temperatures. So, while moderately low temperatures can have an effect on us, there are steps we can take to cope with them.