To lose weight, the basic advice is to eat less and move more, but don’t underestimate the power of sleep.
Getting sufficient rest at night reduces the amount of food people eat during the day — about 270 fewer calories on average than adults who are chronically sleep deprived, new research published in JAMA Internal Medicine had found.
If maintained over three years, that would amount to a 26-pound weight loss — just by getting an adequate amount of sleep.
“What is it amazing about this study is that there now could be a new tool that people can use in their daily lives to help them lose weight,” Dr. Esra Tasali, the lead author and director of the Sleep Research Center at The University of Chicago Medicine, told TODAY.
“This is in a way a game changer in our efforts to tackle the obesity epidemic.”
It’s long been known from lab studies that sleep deprivation stimulates appetite, increases cravings for sugar and junk food, and increases weight gain, but researchers didn’t know if anything could be done about it “in real life,” Tasali noted.
To test it out, she and her colleagues recruited 80 overweight people who slept less than six-and-a-half hours per night on average — less than the seven to nine hours of sleep recommended by the American Academy of Sleep Medicine.
They were then randomly assigned to one of two groups for two weeks:
Sleep extension, where the participants received personalized “sleep hygiene” counseling to help them find ways to sleep longer — with the goal of staying in bed eight-and-a-half hours per night.
Control group, where the participants continued their usual sleep habits.
The researchers didn’t give them any diet or exercise advice, and didn’t ask them to keep track of their hunger, appetite or food intake. To keep the study in real-life conditions, the participants slept at home, rather than in a sleep lab, and wore devices to track their sleep cycles.
Their caloric intake was measured with a urine-based test for the most accurate results.
It turned out the participants who received sleep hygiene counseling were able to sleep more than an hour longer per night than the control group, and they ate less — up to 500 fewer calories per day — despite no other lifestyle changes. They also lost about 1 pound, while the control group gained just under a pound.
Hunger and lack of sleep are connected
So what’s going on here? It basically has to do with appetite-regulating hormones, Tasali said.
“Sleep is a state where every cell in the body gets benefit,” she noted. “We better regulate our heart rates, our fat cells, our hormones, and overall, what we call our metabolism.”
Ghrelin, for example, is a hormone that stimulates appetite. It increases with sleep deprivation, but its levels are lower in a fully rested state, so a person feels less hungry, Tasali said.
The brain also has reward centers that are activated when people are sleep-deprived, so they crave more carbohydrates or junk food. Those reward centers are better regulated when people are rested, so “you don’t have that craving for that extra chocolate bar,” she added.
Bottom line: Losing weight all comes down to comprehensive lifestyle change, said NBC News Health and Nutrition Editor Madelyn Fernstrom, who called the new study carefully done.
“Increasing data like these show that food intake, activity, sleep and stress are all important components for successful weight loss,” she noted. “Everyone is different, and figuring out where you are vulnerable — and fixing that — is the key to long term success.”
Fernstrom said the new research provides compelling evidence that when chronic nightly sleep deprivation is restored to a healthy number of hours — around eight — food intake is reduced. There are clearly connections between metabolic signaling and sleep deprivation, with impact that’s likely both behavioral and biological, she added.
But it’s not about sleeping more if you’re already getting enough rest, both experts cautioned. Adults who slumber more than nine hours a day may not be getting healthy sleep anymore or eating less, Tasali said.
How to get adequate sleep:
To get the recommended seven to nine hours of sleep a night, participants in the study received some of these tips:
Limit the use of electronic devices before bedtime: This was “the most effective intervention in our sleep hygiene program,” Tasali said.
Read an old-fashioned paper book around bed time: The participants were surprised just how useful it was to wind down and begin to fall asleep.
Reduce light exposure: It’s a wake-up signal to the brain. You should also limit activities that are stimulating or engaging, keeping you from slumber.
Organize your morning routine a little better: Preparing your lunch bag the night before and other small changes can save you 15-20 minutes in the morning, allowing more time for sleep.
People in the study were surprised how much of a difference all the tips made in their lives, Tasali said.
“They were feeling more energetic, in a better mood,” she noted. “(Sleep) is not just for the brain, but for the body.”