Cold

Winter holds many pleasures; there are warm cups of something to be lovingly held, brisk walks to be taken, beds to be nestled into and loved ones to be snuggled. Now it seems that in addition to all of that the cold of winter may encourage your body into producing healthy brown fat.

People with high levels of brown fat, as supposed to the more problematic “white fat”, tend to be leaner and have lower blood sugar levels. It has been shown that white fat cells can turn into brown fat cells but these researchers wanted to see what might be responsible for increasing brown fat levels.

The study involved men aged between 19 and 23 years who were followed for a period of four months. During the study the subjects lived their normal lives except that at night they slept in a private room where the air temperature was varied. In the first month the temperature was kept at 24 degrees Celsius overnight, a temperature regarded as “neutral” in that the body does not need to work to either keep or lose heat. In the second month the temperature was lowered to 19, in the third it was returned to 24, and in the fourth month it was set to 27.

Throughout the four months the researchers measured the men’s brown fat levels using PET/CT scans as well as measuring changes in metabolism via muscle and fat biopsies.

The results showed that the mild cold of 19 degrees Celsius increased the subject’s brown fat activity by about 30-40 per cent. These increases in brown fat were accompanied by greater sensitivity to insulin and an increased rate of energy burning after eating.

The researchers conjecture that this may suggest that lower temperatures could help in diabetes management. Surely Scandinavian Diabetes Spas cannot be too far away! The other obvious conclusion is that the proliferation of central heating around the world may be playing a role in the epidemic of overweight that we are experiencing.

So if you want to shed a few kilos it may be that you need to turn the thermostat down a few degrees or, even better, burn less energy and use less central heating. For Southern Hemisphere readers of course, that might make the cold winter evenings easier to bear, or perhaps it is just cold comfort.