Life

Your Climate-Controlled Home Is Making You Fat

by Pamela J. Hobart

All of the fat in your body is not created equal. Specifically, some of it is brown. The brown fat is good fat, because it is associated with a lean body composition and healthy blood sugar levels. So, scientists have begun studying how people can turn more of their regular old white fat into brown fat, and at least this much is becoming clear: a cold environment stimulates brown fat production.

Researchers from the National Institute of Diabetes and Digestive and Kidney Diseases and the National Institutes of Health figured this out pretty simply, by sticking some men in rooms of different temperatures for a month at a time. As compared to the "room temperature" baseline, the warm room decreased their brown fat amounts, but the feels-kinda-cold room increased their brown fat amounts. These brown fat gains, of as much as 30 or 40 percent, improved the men's blood sugar levels and ability to burn energy from food. The cold room men were therefore less likely to gain weight.

In additionally good news, keeping your environment cold, while uncomfortable, doesn't appear to carry any real health risks. (Intermittent fasting can also help you to re-regulate your insulin resistance and blood sugar levels, but its dangers are less well-known and at least somewhat more substantial). You might have to go to pretty significant lengths to keep yourself cool enough for the brown fat benefits, though. Especially if you spend time in older buildings, you'll know that they're difficult to air condition with window units in the summer but often over-heated by radiators in the winter.

Even as your resident skeptic, though, keeping cooler is a recommendation I can endorse. Evolution-obsessed armchair biologists will probably overhype this finding as evidence that we're living in environments that are too unhealthily modern. But keeping cool isn't dangerous, and it does make sense that we would have lived in less climate-controlled environments for almost all of human history. Besides, a drop in body temperature helps many people to sleep better, and cold showers can improve circulation, recovery time, and mood. So maybe it's time to rough it a little indoors and learn to love the cold — because no 70 degree room temperature is as pleasant as a healthy weight feels, as Kate Moss once said.