01/27/2012 11:26 am ET

Brown Fat Furnishes Physiological Furnace

By Katherine Harmon
(Click here for the original article)

When it comes to the battle of the bulge, putting on more muscle will burn extra calories even when you're resting. But recent research suggests that there might be a particular type of fat that also uses up more energy than the typical off-white stuff that tends to congregate around American midsections: brown fat.

This tissue turns food energy directly into heat. It was thought to exist only in babies, to help them keep warm. But it’s recently been found—in small quantities—in adults, too. Mostly distributed in our necks and shoulders. And a new study finds that when adult men are chilly, those with more brown fat burn through more calories keeping warm. The results are in the Journal of Clinical Investigation. [Veronique Ouellet, et al., "Brown Adipose Tissue Oxidative Metabolism Contributes to Energy Expenditure During Acute Cold Exposure In Humans"]

The researchers found that those subjects with the most brown fat saw the biggest boost in their metabolism when they were subjected to cold for three hours.

Although scientists are interested in brown fat’s obesity-battling possibilities, don't count on a calorie-crunching injection in a meat locker anytime soon. For now, we have to burn calories the old fashioned way—or avoid them in the first place.