A new study shows that exposing mice to cold temperatures increases their body’s production of calorie-burning “brown fat” (Molecular Cell, published online Jan. 8, 2015). You have two types of fat in your body:
• white fat that your body stores when you eat too much or exercise too little, and
• brown fat cells, little furnaces that burn white fat for heat and energy.
Excess white fat increases your risk for heart attacks, cancers and premature death. However, brown fat is good for you. By burning extra calories, it helps you to lose weight, get rid of excess fat in your body, and lower high blood sugar levels to help treat and prevent diabetes. Unfortunately, the percentage of brown fat in your body is very small. If you are overweight, the percentage is even lower.
The Experiment in Mice
Exposing mice to cold temperatures increased blood levels of a protein transcription factor called Zfp516 that:
• causes the body to make more brown fat and
• converts white fat cells into cells that can burn some fat.
One group of mice were placed in warm temperatures, while another group was placed in a cold environment. Both groups were placed on a weight-gaining, very high-fat diet. Those living in the cold produced far more Zfp516 and gained 30 percent less weight.
