Relaxing to the laughs on Jimmy Kimmel or catching up on your DVR of the Real Housewives of Beverly Hills may help you drift off to sleep, but if you leave the TV on all night, you could be doing real damage to your waistline.
Scientists at the National Institute of Health analyzed health and lifestyle data on 43,722 U.S. women aged 35 to 74 who enrolled in a larger study about risk factors for breast cancer and other diseases. While women who used a small nightlight were found to maintain their weight, those who dozed with light or television on were 17 percent more likely to have packed on 11 pounds over the course of the five-year period. The study results were recently published in JAMA Internal Medicine.
How does artificial light affect weight gain?
The scientists speculated that the sleep hormone melatonin was suppressed when the artificial light from the TV disrupted the women’s circadian rhythms. Other factors may have played a role in the weight gain results, as well, though the study results were controlled for age, having an older spouse or children in the home, race, socioeconomic status, calories consumed, and physical activity. Find out more on how blue light can affect your health.
“Although poor sleep by itself was associated with obesity and weight gain, it did not explain the associations between exposure to artificial light while sleeping and weight,” said corresponding author Dale Sandler, PhD, chief of the Epidemiology Branch at the National Institute of Environmental Health Sciences (NIEHS), part of NIH, in a press release. (Also, these bizarre things can happen when you gain weight.)
“Unhealthy high-calorie diet and sedentary behaviours have been the most commonly cited factors to explain the continuing rise in obesity,” notes Lead author Yong-Moon (Mark) Park, M.D., PhD. “This study highlights the importance of artificial light at night and gives women who sleep with lights or the television on a way to improve their health.”