A new study has found sleeping more may actually help you fight a genetic predisposition to gain weight.
“The less sleep you get, the more your genes contribute to how much you weigh. The more sleep you get, the less your genes determine how much you weigh,” says lead author Nathaniel Watson, a neurologist and co-director of the University of Washington Medicine Sleep Center in Seattle.
There have been numerous studies in the past demonstrating the connection between sleep and weight, but this study looks specifically at the role of genetics.
Watson and his colleagues analyzed self-reported data on height, weight and sleep duration of 604 pairs of identical twins and 484 sets of fraternal twins in the University of Washington Twin Registry.
Sleep needs vary among individuals, but here are some nightly guidelines used in the study:
People were considered to get short sleep if they slept less than seven hours a night, normal sleep if they slept seven to 8.9 hours, and long sleep if they slept nine hours or more.
The average age of participants was about 37 years; average sleep duration was 7.2 hours a night.
Among findings published online from the American Academy of Sleep Medicine:
•Those who slept longer at night had lower body mass index (BMI), based on weight and height, than those sleeping less.
•People who sleep less increase their genetic risk of an elevated BMI, Watson says.
For twins averaging more than nine hours of sleep, genetic factors accounted for about 32% of weight variations; for those sleeping less than seven hours, genetic factors accounted for 70% of weight variations. For those sleeping seven to nine hours, 60% of the variation was due to genetic factors. Other factors that affect BMI include environmental ones.
Both sleep need and BMI are inherited traits, Watson says. “But we see differences in how much twins weigh based on their sleep duration,” he adds.
Researchers don’t know which genetic pathways involving weight are influenced by sleep, but they might include those involving hunger, satiety, fat storage, metabolism or other physiological functions.
Scientists have known for years that sleep deprivation increases levels of a hunger hormone and decreases levels of a hormone that makes you feel full. The effects may lead to overeating and weight gain.
Getting the proper amount of sleep not only helps you maintain a healthy weight, but can also improve the appearance of your skin making you look younger, improve your mood, and help you perform at your mental and athletic peak.
Below are the “Average Sleep Requirements by Age” issued from the National Sleep Foundation so you can make sure you are getting adequate sleep.
Average Sleep Requirements by Age
|1-3 years old||12-14 hours|
|3-5 years old||11-13 hours|
|5-12 years old||10-11 hours|
|13-19 years old||9 hours|