Sleep is your friend. And it’s a friend that can aide you in burning calories. A study published in the
Annals of Internal Medicine establishes that sleep — and sleep alone — is one of the most powerful diet tools ever identified.
The study compared two groups of overweight non-smokers on calorie restricted diets for 14 days. One group got 8.5 hours of sleep per night, and the other 5.5 hours of sleep per night. Both groups ate roughly 1,450 calories-a-day. After two weeks, the people who slept more lost more fat than the group who slept less. More than half of the weight loss during the 8.5 hours of sleep was fat versus only one quarter of the weight loss during the 5.5 hours of sleep. People literally burned fat while they slept.
The metabolic rate is down-regulated with less sleep. Translation: When you sleep less, your body starts to burn calories at a slower rate to preserve energy. In the study, people burned on average 400 more calories by sleeping for 3 more hours — that’s an additional 2,800 calories burned in just one week. With less sleep, the body seeks to meet the increased metabolic needs of longer waking hours by shifting into a lower gear, so to speak, that burns fewer calories and less fat.
Another study done by National Institute of Health Clinical Center discovered that by turning down the thermostat while you sleep could help speed up your metabolism. The study involved 31 healthy people. Some slept in a 75-degree room or a 66-degree room.
Researchers found that the colder sleepers burned more than 7 percent more calories than the warm sleepers—likely because their bodies were working to raise their core body temperature to a stable 98.6 degrees, says study author Francesco Saverio Celi, MD, MHSc, of the National Institute of Diabetes and Digestive and Kidney Disease. So, just think, if you lowered your thermostat to 66 degrees at bedtime, you could burn an extra 100 calories, over the course of 24 hours.
Getting those z’s definitely sounds a lot more appealing than late nights, especially if you’re a calorie counter.