A: Maybe. Cold weather may stimulate special tissue in your body which burns energy to keep you warm.
[Image source: iStockPhoto | Evgeny Sergeev]
Have your say
Would you take a cold shower every day for six years to lose weight?
Conditions of Use
Winter is here and with it, cold, bleak, short days where it’s easy to just lie around inside, eating comfort food instead of summer salads.
But could exposure to the cold help counteract our tendency to stack on extra kilos beneath our winter woollies?
Potentially yes, says Dr Paul Lee of Sydney’s Garvan Institute of Medical Research, who studies the impact of cold exposure on humans. In the interests of his research, he even elected to subject himself to cold showers daily to explore a theory about how the cold changes the body’s metabolism.
“Yes, that is true, I did take cold showers but I am not recommending it!” he says.
Lee believes cold exposure might have a role in fighting the obesity epidemic which has seen two-thirds of Australians become overweight or obese. Worldwide, there are now more people overweight than underweight.
It turns out cold temperatures stimulate the creation and activity of a special type of tissue in the body called brown fat, which, under the right conditions, burns energy to generate heat to keep us warm.
Fighting fat with fat
Brown fat is a type of fat, but strangely, it could help make you thin.
It functions quite differently in the body from the fat we’re familiar with in the bulges that appear around our tummies, legs, arms and hips. That fat, known as white fat, is made up of cells which serve as a store-house for the fat that accumulates when we eat too much and don’t exercise.
But brown fat, which exists in only small amounts in the lower neck area and collar bone area, contains cells that serve to burn white fat and in doing so, generate the release of energy as heat.
“You can think of brown fat as like a generator, a power house. It can basically combust excess energy and transform it into heat which is lost to the environment,” Lee says.
Lee’s research has shown you need not subject yourself to Arctic conditions to stimulate the fat-burning properties of brown fat. It starts burning kilojoules when stimulated by temperatures as high as 19°C for as little as six hours per day.
No magic bullet
So exposure to cold can stimulate the creation and fat-burning activity of brown fat.
But, “unless people are exposing themselves to cold continuously, brown fat is not active all the time,” Lee warns. What’s more “if a person is not careful with their diet, the extra energy burnt during cold exposure can easily be compensated by extra food intake.”
In other words, our Western tendency to rug up, stay cosy and over-eat in winter means we may not activate our brown fat or the calorie-burning powers that come with it.
“A bout of exercise like jogging can burn energy, but if that is done infrequently in the setting of general over-eating, then weight loss benefits are lessened,” Lee says.
Before you take off your clothes…
Lee says his work may one day lead to drugs that could mimic the beneficial effects of cold on the body, without the cold exposure.
In the meantime, if you want to try getting a little more chilly occasionally, that’s fine. But Lee doesn’t suggest anything as radical as switching to cold showers daily.
Like training for a marathon, you have to train yourself for exposure to the cold, slowly building up your tolerance and enabling your body to become “thermally fitter”, he says.
As with most weight loss methods, losing kilos tends to be challenging and exposure to cold temperatures alone is unlikely to be the answer. But it might help a bit.
“Boosting brown fat may be another strategy [to weight loss] but diet and exercise are certainly the two most studied and evidenced methods,” Lee says.
Dr Paul Lee discusses brown fat
Brown fat facts
- Until recently, it was thought only small animals and babies had stores of brown fat but it has since been discovered that adult humans also have it. But whether everyone is born with the same amount of brown fat isn’t yet known.
- Most humans have between 50g and 200g in the lower neck area and around the collar bones.
- While that may not seem like much fat to conquer obesity, it is extremely metabolically active tissue and if kept continuously active, it could burn as much as 4.5kg of white fat in a year.
- Dr Lee’s ICEMAN study found that cool environments stimulate development of brown fat, while warm environments stimulate the loss of brown fat.
- Animals with lots of brown fat are lean and protected from diabetes, obesity and fatty liver disease, which may cause permanent liver damage.
Endocrinologist Dr Paul Lee spoke to Jennifer King.