Recent studies have found a correlation between cooler sleeping environments and metabolic health, relating to the volume of “brown fat” that is stored in a person’s body.
“Brown fat” is one of two types of fat found in mammals, along with the more common “white fat.” An abundance of brown fat is found in newborns and hibernating mammals, generating body heat for those who do not shiver.
Research has shown that this type of fat is metabolically active, unlike white fat. It takes sugar out of the bloodstream to burn calories and maintain the body’s core temperature.
It was previously thought that adults didn’t have brown fat stores in their bodies, but recent studies have detected small amounts stored in their necks and upper backs.
In a new study, five healthy male adults volunteered to sleep in climate-controlled rooms over the course of four months. Their blood-sugar and insulin levels were tracked throughout, along with their caloric expenditures. At the end of each month, they measured the amount of brown fat found in their bodies.
After four weeks of sleeping in cooler temperatures (66º F), the volume of brown fat had almost doubled, and improved insulin sensitivity was also seen.
By sleeping in a cooler room, adults could over time add to their stores of brown fat and lessen their risk for diabetes and other metabolic health problems.
To learn more, read this article: “Let’s Cool It in the Bedroom” by Gretchen Reynolds from the New York Times.