Luxor Nursing and Rehabilitation at Mills Pond Sleep Warning: Study Shows Falling Asleep with the TV on Can Lead to Weight Gain

If part of your nighttime routine is flipping through the channels and dozing off while watching a movie or sporting event, you may want to instead curl up with a good book.

In a study of nearly 44,000 U.S. women that was originally designed to find clues to the cause of breast cancer, the National Institutes of Health found that too much exposure to artificial light at night could lead to weight gain.

When the women were enrolled in the study, they were asked if they slept with: no light, a small nightlight in the room, light outside the room, and light or television on in the room.

Women who said that they sleep in a room with a light or TV on were most likely to gain 11 pounds over the next five years over any other category of sleeper, and they were around 30 percent more likely to become obese.

The study concluded that exposure to artificial light at night (ALAN) could be a risk factor for weight gain and development of obesity. 

The reason for the possible connection is the internal body clock that promotes sleep at night.

“Evolutionarily we are supposed to be sleeping at night, in a dark place,” lead author Dale Sandler told NBC News. “It’s much more important than people realize for a whole variety of health reasons.”

Our internal clocks regulate, among other things, metabolism and blood pressure. Research has found that people who work at night and sleep during the day are at higher risk for hypertension, diabetes, and obesity. 

 The National Institutes of Health concluded that further research on this specific issue is necessary in order to draw more concrete conclusions.