In the past few years, Americans have been made aware that over half (65%) of the country's population is obese. The "obesity epidemic" has been blamed on everything from fast food and trans fats to sedentary jobs and remote controls. Recent research at Stanford University and other facilities indicate that there may be a strong connection between sleep deprivation and the inability to lose weight.
When researchers at Columbia University studied the sleep habits and weight patterns of 6,115 people, they discovered that those who slept two to four hours a night were 73% more likely to be obese than those who slept seven to nine hours. People who slept five or more hours a night were 50% more likely to be obese, and those who slept six hours were 23% more likely to be obese. The researchers also found that those who got 10 or more hours of sleep a night were 11% less likely to be obese.
Getting less than eight hours of sleep a night appears to increase levels of the hormone that makes you feel hungry (ghrelin) and decreases levels of the one that makes you feel full (leptin). You won't necessarily crave a huge breakfast. You'll just have a nagging feeling all day that you need to eat, and regardless of what you eat, you'll never feel satisfied - a perfect recipe for weight gain.
The idea that poor sleep habits are to blame for weight gain goes a long way in explaining why new mothers can't lose their "baby weight," why college freshmen are famous for gaining the "freshman ten," and why shift workers have higher obesity rates. Many people suffer from chronic worry and stress that interferes with sleep, and as we get older most of us develop aches and pains that can cause wakefulness and interrupt sleep.
The National Sleep Foundation estimates that 65% of Americans get less than the ideal eight hours of sleep per night. In fact, the average during the week is just 6.9 hours a night. Most people are able to get a few more hours on the weekends, but ghrelin and leptin don't seem to believe in playing catch-up. In a sleep-appetite study at the University of Chicago, those who slept four hours not only showed increased amounts of hunger-stimulating ghrelin (think "gremlin"), they also said that they craved high-carb foods like cake, ice cream, pasta, bread and candy.
Obviously, getting more sleep is easier for most people than eating a low-calorie diet or following a strict exercise program. Going to bed a little earlier-instead of snacking your way through another TV show-could be the easiest component of successful weight loss. If nothing else, you'll feel more energetic in the morning, which in itself can put that extra spring in your step than can burn a few more calories.
According to Eve Van Cauter, lead investigator for a University of Chicago sleep study, "Our body is not wired for sleep deprivation. The human animal is the only one that does this."
These new findings about sleep and weight loss give new meaning to the saying, "You snooze, you lose."