According to new research, sleeping with TV or other lights on can affect your metabolism and increase the risk of weight gain or even obesity.
On Monday, the National Institutes of Health published the research report suggesting that excessive exposure to light at night could increase the risk of health issues.
The lead author of the study and a scientist with the National Institute of Environmental Health Sciences Dale Sandler said, “Evolutionarily we are supposed to be sleeping at night, in a dark place. It’s much more important than people realize for a whole variety of health reasons.”
Previous studies revealed that daily exposure to light and darkness can affect metabolism, blood pressure, sleep-promoting hormones, and other bodily functions.
New research suggests that disrupting the typical sleep-wake cycle may lead to poor health, increasing the risk of obesity, high blood pressure, diabetes, and depression.
The study researchers looked at the data of health and lifestyle of nearly 44,000 American women enrolled in an ongoing study that seeks clues to potential causes of breast cancer. They analyzed their sleep, light exposure, and weight, but not on breast cancer.
The findings of the study were published in JAMA Internal Medicine.
The researchers found that women who reported sleeping at night in a room with lights or television on were more likely to gain around 11 pounds for about five years than those who slept in darkness. They also found that those women were about 30 percent more likely to become obese.
Sandler explained that the added weight was not from things such as snacking at night, as the analysis accounted for other variables, which could cause weight gain, such as physical activity, diet, and sleep duration.
Sandler said it is likely that similar results would be found in men as well. Dr. Phyllis Zee, an expert in sleep and circadian rhythm disorders at Chicago’s Northwestern University, said, “The study is important because it highlights a behavior that can be easily changed to reduce the risk of gaining weight. Properly timed light should be considered as part of a healthy lifestyle, along with exercise and good nutrition.”