IT may be the world's easiest weight-loss plan, involving no exercise or dieting.
Scientists claim you can shiver yourself slim simply by turning the heating down.
Most houses in the winter are heated to around 21C but researchers at Maastricht University Medical Centre advise turning the thermostat down to between 15C and 17C for a few hours a day.
Experts claim that because we spend so much time indoors, often in overheated homes and offices, our bodies do not naturally burn calories to keep warm.
It is a trend which has crept up on us over the past century as we have become more adept at controlling the temperature in our surroundings.
But temperatures closer to what it is like outside might be more beneficial to health.
Simply being colder raises the metabolic rate – the speed at which calories are burnt – by 30pc, and shivering can burn around 400 calories an hour as it increases the metabolic rate fivefold.
Researchers say although shivering can feel uncomfortable, lowering the temperature so you just feel chilly might be an easy option for people who struggle to keep up diets and exercise regimes.
"We suggest that regular exposure to mild cold may provide a sustainable alternative strategy for increasing energy expenditure," said the lead author Dr Wouter van Marken Lichtenbelt. "Thermal comfort in the built environment may increase our susceptibility to obesity and related disorders.
"Mild cold exposure increases body energy expenditure without shivering and without compromising our precious comfort. More frequent cold exposure alone will not save the world, but it is a serious factor to consider in creating a sustainable environment together with a healthy lifestyle."
The Dutch team found that people who spent six hours at 15C for a period of 10 days had increased levels of calorie-burning brown fat, felt more comfortable and eventually shivered less.
Previous Japanese research has shown a decrease in body fat after people spent two hours per day at 17C for six weeks.
"A little cold a day keeps the doctor away," said Dr Lichtenbelt. "In the past century, several dramatic changes in the daily living circumstances in western civilisation have occurred, affecting health. For example, we are much better able to control our ambient temperature.
"Consequently, we cool and heat our dwellings for maximal comfort while minimising our body energy expenditure necessary to control body temperature. By lack of exposure to varied temperatures, entire populations may be prone to developing diseases such as obesity." (© Daily Telegraph, London)