Hit that off button, y'all!

By Meghan Overdeep
June 11, 2019
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Drifting off to sleep with the television on may not be as harmless as you think. The National Institutes of Health released new evidence Monday that too much exposure to light at night could pose health risks.

Preliminary research published in JAMA Internal Medicine suggests that sleeping with the TV or other lights on can mix up your metabolism and lead to weight gain and even obesity.

"Evolutionarily we are supposed to be sleeping at night, in a dark place," lead author Dale Sandler, a scientist with the National Institute of Environmental Health Sciences, a division of the National Institutes of Health, told USA Today. "It's much more important than people realize for a whole variety of health reasons."

In analyzing the health and lifestyle data on nearly 44,000 U.S. women enrolled in an ongoing breast cancer study, scientists discovered that those who reported sleeping at night in a room with a television on or a light were more likely to gain at least 11 pounds over about five years than those who slept in darkness. They were also about 30% more likely to become obese.

Sandler told USA Today that it's likely similar results would be found in men.

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Scientists still aren't sure of the exact reason, similar results linking prolonged light exposure and weight gain have been found in animal research and smaller human studies. It is believed that the disruption in release of hormones related to sleep and appetite may be involved.