Sleep longer to lose fat, study finds
Share with others:
There really is an easy way to lose body fat.
You can sleep it off, according to researchers from the University of Chicago.
The researchers studied 10 overweight men and women for two separate two-week periods in a sleep lab. During both periods, participants in the study ate the same calorie-restricted diet. During one period, participants slept for 8.5 hours a night. During the other, they slept for just 5.5 hours.
The researchers found the participants lost the same amount of weight during both periods, an average of about 7 pounds.
But during the sleep-restricted period, the participants lost mostly muscle.
"The amount of human sleep contributes to the maintenance of fat-free body mass at times of decreased energy intake," concluded the study, which was funded chiefly by the National Institutes of Health and published in the Annals of Internal Medicine. "Lack of sufficient sleep may compromise the efficacy of typical dietary interventions for weight loss and related metabolic risk reduction."
"I hope there are more studies like this," said Christine Mackey, who practices internal medicine at Allegheny General Hospital. "It makes sense physiologically."
She said the amount of sleep you get has an effect on the production of ghrelin, a hormone the body produces that is essential to weight management. It stimulates the liver to produce more sugar, slows metabolism and decreases the body's ability to burn fat.
An earlier study indicated that "volunteers who had just two hours less of sleep [each night] had a rise in their level of ghrelin," Dr. Mackey said. "They experienced more hunger and they lost less fat."
Another important hormone affected by the amount of sleep we get is leptin, said Ryan Soose, director of the Division of Sleep Surgery at the University of Pittsburgh Medical Center.
"Leptin is a hormone released by fat that provides information to the brain about energy metabolism," Dr. Soose said. "Reduced sleep is associated with lower leptin levels. That correlates with insulin resistance [a precursor to diabetes] and is related to other hormonal changes associated with weight gain."
First Published November 1, 2010 12:00 am
