Brown fat is present in newborns, one of its primary functions is to generate body heat by burning calories. Brown fat is activated by cold temperatures – it’s a way newborns try to keep warm. Three preliminary studies published in an April 2009 issue of the New England Journal of Medicine suggest that brown fat when present in adults may help us burn calories. For many years it was thought that adults did not retain brown fat but these new studies found that some thinner adults may have this fat and possibly could burn more calories without additional exercise. PET (positron emission tomography) scans were used to look for active brown fat deposits in adults. The researchers found that brown fat became more active in cold temperatures similar to findings in infants. This is brand new research that needs to be evaluated in future studies but may possibly lead to future new treatments for weight loss and the prevention of heart disease and diabetes.