Sleeping in the glow of artificial light may sabotage weight loss

Sleeping under the glow of a television screen may result in gradual weight gain, a new study warns. Researchers with the NIH's National Institute of Environmental Health Sciences looked at women ages 35 to 74 years and found a link between sleeping with artificial light, weight gain, and increased risk of becoming obese. The study joins a growing body of research into the negative effects of artificial light.

Artificial light is everywhere — it comes from your phone, smartwatch, tablet, television, and light bulbs. Attempts to reduce nighttime exposure to artificial light is close to futile for many people. Exposure to artificial light often comes from one's surrounding environment, including street lamps outside one's home and glowing billboards on the side of the road.

The vast presence of artificial light has raised a number of concerns from both a health and an environmental standpoint. Wildlife suffers from exposure to artificial light at night, according to past research, and artificial light is known to disrupt sleep quality. Poor sleep quality is highly linked to both short- and long-term health issues.

In the latest NIH study, researchers looked at survey data from more than 43,000 women who didn't report sleeping during the day, weren't pregnant, had no history of heart disease or cancer, and who weren't shift workers. Each participant provided information about their sleeping habits, namely whether they were exposed to small night lights, light outside of their room, or from a light or television in the room.

A small amount of artificial light at night, such as a night light, wasn't linked to weight gain in participants. However, women who slept with a TV or light on at night were found to be 17-percent more likely to gain 11 pounds or more over the study's followup period. Artificial light from outside the participant's room was found to have a 'modest' association with weight gain.