In recent decades, people in affluent countries have gradually kept turning up the thermostat in winter. But by doing this, we turn down the body’s own thermostat and are probably contributing to the obesity epidemic!

Researchers in England have noted a cultural shift in people’s expectations of “thermal monotony” since the 1960’s. Widespread use of central heating has become the norm.

But by reducing exposure to indoor cold, we minimize the need for our bodies to expend extra energy to keep us warm.

When we are exposed to cold, several things happen:

the blood vessels in our skin contract, lowering skin temperature
our skeletal muscles begin to contract rapidly in what we call shivering, which consumes energy and generates heat. This is called thermogenesis.

These English researchers have shown that in Britain, average living room temperatures have risen almost 2 degrees since 1978 and bedroom temperatures have risen 5 degrees in the same period. In the USA, living room temperatures remained stable, but bedroom temperatures increased by almost 2 degrees, also.

These changes in thermogenesis help explain how room temperatures influence energy balance and weight maintenance.

New research shows that “brown fat” is actually a thermogenic organ which dissipates energy in the form of heat. This is not like “white fat” which acts as an energy storage depot.

Cooler temperatures activate “brown fat” causing it to expend calories to produce heat. Experiments have shown that by decreasing the ambient temperature from 72 degrees to 60 degrees, brown fat is activated, and the resulting energy expenditure could result in the loss of almost 9 pounds in a year!

It would appear that science has established a causal link between increased time spent in thermal comfort and weight gain in the general population.

What does this mean to you? Here are three suggestions:

Turn down the thermostat a degree or two during the day and wear a sweater or coat. You will expend more calories and save on your heating bill!
Drop your bedroom temperature 8-10 degrees at night and throw on an extra blanket. This should help stimulate your brown fat to burn energy to keep you warm.
Use an electric blanket to warm the bed before retiring, but don’t sleep with it on all night. Let your body produce energy to keep you warm.

Surprisingly, it may be a PositiveChoice to live a little cooler, turn up the body thermostat, and burn more calories!