Scientists have find out why more people die from heart disease during the winter.
The increase in deaths from cardiovascular illness in cold periods was previously blamed on people doing physically demanding tasks, like shovelling snow, but doctors did not understand the biology behind the seasonal rise.
Now researchers claim that a kind of body fat previously thought to be beneficial leads to a narrowing of blood vessels when a person is exposed to low temperatures.
Brown fat, which is used by the body to generate heat, was previously thought to have a positive effect on a person’s health as it reduces the body’s reserves of flabby white fat.
However, scientists found that when brown fat’s heat generation is activated by the cold it speeds up the growth of atherosclerotic plaque, made up of fat and cholesterol, in veins and arteries.