Women could gain weight by sleeping with TV on, study claims

HealthSleeping with the TV on may make you gain weight			By Associated Press

HealthSleeping with the TV on may make you gain weight By Associated Press

If you've been working hard on that "summer bod" but not seeing the results you expected - the answer might be right here - falling asleep with the TV on could be making you gain weight.

Based on a survey of 43,722 women aged 35-74 with no history of cancer or cardiovascular disease, who weren't shift workers, daytime sleepers or pregnant at the start of the study, the scientists asked about how much light inside and outside the room participants slept with.

Women in the study had medical exams and filled out health and lifestyle questionnaires when they enrolled and periodically after.

"What is novel with this paper is that it is a longitudinal study comparing the weight of the same individuals at baseline and more than five years later".

Respondents reported exposure to artificial light at night (ALAN) from televisions, smart phones, computers, e-readers and tablets, which emit a short wavelength-enriched light or "blue light" that previous research has linked to melatonin suppression and circadian disruption. Those who reported sleeping at night in a room with a television on or a light were more likely to gain at least 4.9 kgs over about five years than those who slept in darkness.

"There was a dose response, in that the more light in the room the stronger the association", Sandler said.

Also, the scientists wondered if not getting enough rest factored into the findings.

While the study doesn't prove that sleeping with a light on causes weight gain, it suggests the two may be linked, the researchers said. She notes that for many who live in urban environments, light at night is more common and should be considered.

In other words, exposure to light at night might represent a "constellation" of factors, including those related to unhealthy behaviors, "all of which could contribute to weight gain and obesity", the authors said.

The findings add to a growing body of evidence suggesting that light at night may be bad for health. These factors included age, having an older spouse or children in the home, race, socioeconomic status, calories consumed, and physical activity.

Lead author Yong-Moon (Mark) Park, M.D., Ph.D., is a postdoctoral fellow in Sandler's group.

Obesity rates in Australia are on the rise. "Further prospective and interventional studies could help elucidate this association and clarify whether lowering exposure to ALAN while sleeping can promote obesity prevention".

Researchers at the National Institute of Environmental Health Sciences (NIEHS) just discovered a dark side to sleeping with the light on.

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services.