Elderly adults are bigger around the middle when they turn up the heat inside their homes during the cold season and have smaller waistlines when their homes stay cool, new research finds. Investigators from Japan will present their study results Friday at the Endocrine Society's 98th annual meeting in Boston."Although cold exposure may be a trigger of cardiovascular disease, our data suggest that safe and appropriate cold exposure may be an effective preventive measure against obesity," said the study's lead investigator, Keigo Saeki, MD, PhD, of Nara Medical University School of Medicine Department of Community Health and Epidemiology, Nara, Japan.Cold exposure activates thermogenesis, to generate body heat, in brown fat. This type of fat is the good calorie-burning fat that prior research found most humans have. However, Saeki said the association between the amount of cold exposure and obesity in real life remains unclear.