Jan. 26, 2011 at 9:34 AM ET
By Linda Carroll
Lowering your thermostat may reduce not only your spending, but also your weight, a new study suggests.
Researchers suspect that rising indoor temperatures in British and American homes may have contributed to the obesity epidemic. The theory is that we burn fewer calories when our bodies don’t have to work as hard to stay warm, according to a report published in Obesity Reviews.
“Research into the environmental drivers behind obesity, rather than the genetic ones, has tended to focus on diet and exercise – which are undoubtedly the major contributors,” said the study’s lead author, Dr. Fiona Johnson, of the UK Health Behavior Research Centre at University College, London. “However, it is possible that other environmental factors, such as winter indoor temperatures, may also have a contributing role.”
Johnson and her colleagues scrutinized data on indoor temperatures in both the United Kingdom and the United States. They found that both British and American households have bumped up their thermostats several degrees over the last few decades.
For example, bedrooms in the U.S. were heated to an average of 66.7 degrees in the late 1980s, versus 68.4 degrees in 2005. The differences were more striking in British bedrooms, where the average temperature climbed from 59.4 degrees in 1978 to 65.3 degrees in 1996.
Studies have shown that slightly chillier temperatures can lead to increased energy expenditures, Johnson noted. And that’s true even when people bundle up.
“Increased time spent indoors, widespread access to central heating and air conditioning, and increased expectations of thermal comfort all contribute to restricting the range of temperatures we experience in daily life and reduce the time our bodies spend under mild thermal stress – meaning we’re burning less energy,” Johnson said.