But after controlling for these factors, as well as for age, race, physical activity, diet, sleep duration and other variables, they found that sleeping with lights on was independently associated with gaining 11 pounds or more, an increase of 10 percent or more in B.M.I., a 22 percent increased risk for being overweight and a 33 percent increased risk for obesity. The study is in JAMA Internal Medicine.
The mechanism is unclear, but the researchers suggest that light may disrupt sleep enough to change levels of appetite-regulating hormones or cause daytime sleepiness that reduces physical activity.
“Getting a good night’s sleep is really important for health,” said the senior author, Dale P. Sandler, an epidemiologist with the National Institutes of Health. “A very simple thing people can do to reduce the risk for obesity is to turn off the lights before going to sleep.”
Read the complete article: Sleeping With the Lights on Tied to Weight Gain
This article was first published by Nicholas Bakalar