Cold Temperatures Change Fat Behavior

Body fat can burn more calories in colder temperatures, a study has found. The study examined belly fat in 55 people. Samples were taken in the summer and winter. Belly fat is generally considered to be white fat, which does not burn many calories. But the winter belly fat behaved more like brown fat, which burns calories at a higher rate. Babies have high levels of brown fat, which is believed to help keep them warm. The study also had people put ice packs on their thighs for 30 minutes. The fat underneath the ice pack was then examined. It was expressing genes that are active in brown fat, but not white fat. These effects were limited in obese people, however. Researchers are interested in finding other ways to make white fat behave more like brown fat. This could lead to treatments for obesity, or prevention strategies. The study was published Oct.