An interesting study at the University of Colorado involving a two-week A/B test on sleeping and weight turned up some interesting results.
Though sleep deprivation burns more calories (because you’re awake and functioning more), the same sleep deprivation leads to increased food consumption. Thus those in the test who were restricted to five hours of sleep a night — and had to stay up until midnight — actually gained weight at the end of the first week.
Those in the other split-test group who were allowed nine hours of sleep a night did not experience the weight gain. (The two groups alternated weeks of five-hour and nine-hour nights.) When the two groups were switched, however, the former nine-hour sleepers, now on a five-hour regimen, also gained weight.
The group that was put on the five-hour sleep pattern for the first week saw some weight loss during week two when they went on nine hours of sleep a night, but they failed to lose the weight they had gained during week one!
The five-hour sleepers not only ate more, but tended to snack a lot after dinner as well.
Kenneth Wright, director of the university’s sleep and chronobiology laboratory, said part of the change was behavioral. Staying up late and skimping on sleep led to not only more eating, but also a shift in the type of foods a person consumed.
“We found that when people weren’t getting enough sleep, they overate carbohydrates,” he said. “They ate more food, and when they ate … also changed. They ate a smaller breakfast and they ate a lot more after dinner.”
The average weight gain during the week of deprived sleep was two pounds. (Add that up over the course of a month — or a year!)
Also, obviously, if you don’t get enough sleep, you tend to be tired. Tired people are less likely to exercise than well-rested individuals. When you are tired, your body craves simple carbohydrates (sugars) for a burst of energy, but simple carbs are the last thing you want to be consuming if weight loss is your goal.
The manufacture and release of two main hormones that regulate hunger are influenced by sleep deprivation. Even minor periods of sleep deficit increase the secretion of Ghrelin, which is a hormone that not only increases appetite but also increases abdominal fat deposition. Sleep deficit also decreases the release of leptin, a hormone that tells you to eat less. Sleep-deprived people are likely to eat more and to store more fat in their abdomens.
If you are one of the 40 percent of Americans who don’t get all the sleep they should, and you are looking for a healthy, sustainable, rational way to lose weight, consider getting more sleep as an integral part of your plan. And sleep your way skinny!