Researchers at Laval University in Quebec looked at 276 people for six years who were part of a larger Canadian study.
Sleep duration was determined from a questionnaire and the participants were classified into three groups: short sleepers slept five to six hours a night, the average got seven to eight hours, and the long sleepers put in nine to 10 hours of sleep every night.
Some of the findings:
- Over six years, short sleepers were 35% more likely to gain 11 pounds than average-duration sleepers.
- Over the same time period, long sleepers were 25% more likely to gain 11 pounds than average-duration sleepers.
- Short sleepers gained 58% more around their waists and 124% more body fat than the average sleeper.
Sleep Sweet Spot?
Researchers also think there might be an "optimal sleeping time" to stay healthy.
The American Academy of Sleep Medicine recommends that adults sleep between seven and eight hours a night.
Study researcher Jean-Philippe Chaput of Laval University says in a news release the findings provide "evidence that both short and long sleeping times predict an increased risk of future body weight and fat gain in adults."
Chaput adds that "these results emphasize the need to add sleep duration to the list of environmental factors that are prevalent in our society that contribute to weight gain and obesity."
A Nation Deprived?
Study authors say people in the United States are losing sleep, with Americans sleeping one and a half to two hours less a night than we did 40 years ago.
Previous studies have shown similar findings linking a lack of sleep to creeping obesity. Researchers say this new study adds to a growing body of evidence showing a sleep connection to weight gain involving fluctuating hormone levels.
According to the American Academy of Sleep Medicine, nearly a third of adults say they sleep less than six hours a night.
Dreams of Good Sleep
Here are some tips for getting good sleep from the American Academy of Sleep Medicine:
- Follow a consistent bedtime routine.
- Establish a relaxing setting at bedtime.
- Get a full night's sleep every night.
- Avoid caffeine or any other stimulants before bedtime.
- Be worry-free at bedtime.
- Don't go to bed hungry, or too full.
- Avoid rigorous exercise within six hours of your bedtime.
- Make your bedroom quiet, dark, and a little cool.
- Get up at the same time every morning.
The study is published in the April 1 issue of the journal Sleep.