According to researchers at the National Institutes of Health, sleeping with a TV or light in the room may be a risk factor for gaining weight or developing obesity. The study, released online in JAMA Internal Medicine on June 10, is the first to discover an association between any nighttime exposure to artificial light while sleeping and gaining weight in females. The findings indicate that cutting off lights at bedtime may decrease the chance for women to become obese.
In the Sister Study, the research team used questionnaire information from 43,722 females, a cohort study that examines breast cancer risk factors and other illnesses. The respondents, aged 35-74, had no history of cancer or cardiac illness, and when the research started, they were not shift employees, daytime sleepers, or pregnant. The research questionnaire inquired if the females were sleeping in the room without light, a tiny night light, light outside the room, or a light or TV.
The researchers used baseline measurements of weight, height, waist and hip circumference, and body mass index, as well as self-reported baseline weight and follow-up data five years later. Using this data, with females who reported sleeping in dark rooms, the researchers were able to study obesity and weight gain in females subjected to artificial light at night.
The outcomes varied with the rate of night exposure artificial light. For instance, weight gain was not connected with using a tiny nightlight, while females who slept with a light or television on were 17 percent more probable to gain 5 kilograms, about 11 pounds or more over the follow-up period.The association with having light coming from outside the room was more modest.
Also, the scientists wondered if not getting enough rest factored into the findings. “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, Ph.D., chief of the Epidemiology Branch at the NIH.
Co-author Chandra Jackson, Ph.D., Head of the Health Equity Group’s NIEHS Social and Environmental Determinants, is interested in sleep health racial disparities. She states that light at night is more prevalent and should be regarded for many living in urban settings. Streetlights, shop front neon signs and other light sources can suppress the melatonin of the sleep hormone and the circadian rhythms’ natural light-dark cycle lasting 24 hours.
“Humans are genetically adapted to a natural environment consisting of sunlight during the day and darkness at night,” Jackson said. “Exposure to artificial light at night may alter hormones and other biological processes in ways that raise the risk of health conditions like obesity.
The writers recognize that the associations between artificial light at night and weight gain could be explained by other confounding variables. However, their results did not alter when analyzes were checked for features that could be connected with nighttime light exposure. These variables included age, home having an elderly wife or kids, ethnicity, socioeconomic status, eaten calories, and physical activity. Also, there were no males in the research.
A postdoctoral fellow in Sandler’s group is the lead writer Yong-Moon (Mark) Park, M.D., Ph.D. He said the study indicates a feasible approach for government health to decrease the occurrence of obesity in females.
“Unhealthy high-calorie diet and sedentary behaviors have been the most commonly cited factors to explain the continuing rise in obesity,” Dr. Park said. “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.”
This press release discusses a finding of fundamental studies. Basic research improves our knowledge of human behavior and biology, which is key to promoting fresh and better methods of preventing, diagnosing and treating disease. Science is an unpredictable and incremental process— every progress in study builds on previous findings, often in unexpected ways. Without the understanding of basic basic research, most clinical developments would not be feasible.