Sleep More, Weigh Less

Sleep for Weight Loss, Continued

We don't want to give the impression that this makeover was effortless; finding time for more sleep does take work. In fact, one of our testers, Natasha Crawford, 33, wasn’t able to stick to the plan for more than two or three nights a week because of a crazy job schedule. But even though she didn’t lose weight, by the end of the plan she had still lost a total of two and a half inches off her waist, bust and hips.

At least two dozen studies have documented that people tend to weigh more if they sleep less, says Sanjay Patel, M.D., a researcher at Case Western Reserve University in Cleveland. In a 16-year study of almost 70,000 women, Dr. Patel and his colleagues found that those who slept five hours or less a night were 30 percent more likely to gain 30-plus pounds than those who got more rest. In fact, some experts believe lack of sleep is one reason for America’s obesity epidemic. The average woman gets six hours and 40 minutes of sleep most nights, according to the National Sleep Foundation -- much less than the seven-and-a-half-hour minimum our experts say healthy women need.

What exactly is the sleep-weight connection? Science shows that sleep deprivation wreaks havoc on hormones that control appetite, cravings and the metabolism of fat. See how these findings translate to your body.

Sleep More, Eat Less
Whether you notice it or not, you probably eat more, sometimes much more, when you’re tired. Proof: Researchers at the University of Chicago allowed people to sleep five and half hours one night and eight and a half on another, then measured how many free snacks the participants downed the next day. They ate an average of 221 calories more when sleepy -- an amount that could translate into almost a pound of fat gained after two weeks! “When women are deprived of sleep, they have an increase in ghrelin -- what we call the ‘go’ hormone -- because it makes you want to go eat more,” says Breus, clinical director of the sleep division at Southwest Spine & Sport in Scottsdale, Arizona, and author of Beauty Sleep. “They also have a drop in leptin, the ‘stop’ hormone that tells you to stop when you’re full.” Not only do you want more food when you’re sleep-deprived, you also want junkier food: Your body craves simple carbohydrates (chocolate, pastries, candy) that it can break down fast for quick energy, explains Breus. “I used to eat a ton of sugar every afternoon,” "Glamour" volunteer Johnson says. “But now I can have just a small piece and feel satisfied.”

Sleep More, Store Less Fat
Even before seeing the number on the scale drop much, our testers noticed other changes. Three weeks into the plan, Braverman easily put on a pair of pants that used to be too snug. And at the two-month mark, Hamilton-Romeo told us, “My stomach is getting flatter and my love handles smaller.” By the end of 10 weeks, she’d shaved almost five inches off her waist, hips, bust and thighs -- even though, at 5’4” and 133 pounds, she wasn’t overweight to begin with. The explanation? “During deep sleep, your brain secretes a large amount of growth hormone, which tells your body how to break down fat for fuel,” explains Breus. “Deprive your body of deep sleep, and when extra calories get stored as fat, there isn’t enough growth hormone to break it down. So your body takes a shortcut and packs it away in your butt, thighs, belly -- wherever you tend to put on weight.” Says Braverman, who lost a total of two and a half inches: “The changes in my body fascinate me, because I really haven’t changed anything except my sleep habits. I eat the way I always have and exercise the same amount, maybe even less because my schedule is tighter now that I have to go to bed earlier!”

Sleep More, Have More Energy
Perhaps not surprisingly, all of the women on our plan said they felt much less tired. And though we told them not to make any conscious exercise changes, a couple of them couldn’t help themselves. “I’ve always worked out,” Barr told us, “but I’m spending more time at the gym because I finally have the energy!” Says Foley, “I used to have days when I’d want to go home and just veg out on the couch; now I’d rather run or do something physical -- a complete revolution in my lifestyle.” Breus wasn’t surprised. “Your perception of how hard or easy exercise is to do is directly affected by how sleep-deprived you are,” he says. Ready to get some of these same benefits?

See the women's amazing weight loss results by clicking on the yellow arrows in the gallery above.