New study; Lower the thermostat, whittle your waistline?
Jacque Wilson, CNN
4:25 PM, Jan 22, 2014
4:26 PM, Jan 22, 2014
You may want to program the thermostat in your office down a couple of degrees today, despite the more-than-chilly temperatures outside. A paper published Wednesday in the scientific journal Trends in Endocrinology & Metabolism suggests doing so could help you lose weight.
Regular exposure to mildly cold temperatures help people burn more calories, according to the paper's authors, who have been studying this phenomenon for more than a decade.
"Since most of us are exposed to indoor conditions 90% of the time, it is worth exploring health aspects of ambient temperatures," lead author Wouter van Marken Lichtenbelt said. "What would it mean if we let our bodies work again to control body temperature?"
Over the last 10 years, Lichtenbelt and his team have discovered several key factors related to this link between fat and temperature.
In 2009, the researchers, and others around the globe, found something called brown adipose tissue -- or brown fat -- in human adults. Scientists had previously believed that functional brown fat was only found in infants. Brown fat is different than the white fat most of us associate with obesity.
Brown fat is thought to play a role in nonshivering thermogenesis, a form of heat production that happens in your body when you're not shivering -- i.e. when the temperature is cool, but not cold. Animal studies have shown that nonshivering thermogenesis activates brown fat cells, which burn calories to create heat.
Lichtenbelt and his team have found that nonshivering thermogenesis is weakened in obese people and in the elderly. And that obese people have less brown adipose tissue than people in the normal weight range.
They've also found that losing weight can help obese people increase their brown fat activity.
More recently, Lichtenbelt and his team showed that a 10-day "cold acclimation period" increased their study subjects' brown adipose tissue and nonshivering thermogenesis.
After spending six hours a day in 59-degree temperatures, the participants shivered less and were more comfortable in the cold. The results suggested to the researchers that "a variable indoor environment with frequent cold exposures might be an acceptable and economic manner to increase energy expenditure."
So what does all that mean for you?
Lichtenbelt suggests varying the temperature in your house and your office by a few degrees over time. Letting the indoor temperature rise and fall will encourage your body to adjust its internal temperature accordingly, he says, increasing your energy expenditure.
"More frequent cold exposure alone is not going to save the world," from obesity, he says, "but is a serious factor to consider for creating a sustainable environment along with a healthy lifestyle."