Falling asleep with TV or lights on? Study says it can increase risk of weight-gain, obesity

Tend to fall asleep with the Tv or your favourite Netflix series running? Bad news ahead! A new study has found out that sleeping with artificial lights on are 17 per cent more likely to gain weight, a study found. The researchers, from the National Institute of Environmental Health Sciences in the US, followed 43,722 women aged between 35 and 74 years old, over a period of at least five years. It found that those who said they sleep with a TV or a light on in the room, gained 11 pounds or more, and had a body mass increase of about 10 percent over a 5-year period.

Exposure to artificial light at night was linked with an increased risk of weight gain and the development of obesity, the study found. The researchers believe that this is because when sleep was disrupted – which has an effect on hormone balance and it makes people seek out calorific food.

The findings, published in Jama International Medicine, found light - especially sleeping with a light or television on in the room - increased the risk of weight gain and obesity. They were also 22per cent more likely to become newly overweight and 33 per cent more likely to become newly obese.

"These results suggest that exposure to artificial light at night while sleeping may be a risk factor for weight gain and development of overweight or obesity," the authors said.

The researchers note that exposure to artificial light while sleeping might reflect other unhealthy behaviours, such as a sedentary lifestyle, and socioeconomic disadvantage.

Commenting on the study, Professor Malcolm von Schantz, from the University of Surrey, said:, "The findings make perfect biological sense.

"We know that light in the late evening will delay our body clocks.

"We know from experimental studies in people that light at night affects our metabolism in ways that are consistent with increased risk of metabolic syndrome.

"These new findings won't change the advice to maintain good sleep hygiene, and avoid light and electronic distractions in the bedroom, but they add further strength to the case for this advice."

 (With inputs from agencies)