Millions of people fall asleep each night in front of the TV — but a new study has found the practice could contribute to an early death.
Researchers at the Northwestern University School of Medicine examined the impact of ambient light on the health and sleeping habits of 552 people between the ages of 63 and 84.
The study found that those who slept with even the slightest ambient lighting were more likely to suffer from diabetes, obesity and hypertension.
“People should do their best to avoid or minimize the amount of light they are exposed to during sleep,” the study’s lead researcher, Phyllis Zee, told CNN.
According to the study, insulin resistance was more likely to occur in the morning after people slept in a room with dim lighting, such as that emitted by a TV set.
Insulin resistance — whereby cells in muscles, fat and the liver don’t respond properly to insulin — is commonly associated with type 2 diabetes, hypertension and cardiovascular disease, according to the American Family Physician.
“We are showing a mechanism that might be fundamental to explain why this happens,” Zee explained. “We show it’s affecting your ability to regulate glucose.”
In turn, data showed that 17.8% of the study’s participants who slept with ambient light at night suffered from diabetes, compared to just 9.8% who nodded off in the pitch black.
Meanwhile, 40.7% of participants who slept with ambient light were obese, while just over a quarter of participants who dozed in darkness met that category (26.7%).
The sleep study also uncovered some other disturbing facts linking light to health problems.
Those who fell asleep in ambient light were more likely to stay awake later and then sleep later the next day.
“We know late sleepers tend to also have a higher risk for cardiovascular and metabolic disorders,” Zee declared to CNN.
Meanwhile, the study also uncovered that less than half of all participants slept for more than five hours per night in a fully darkened room.
Of course, it’s not just TVs that sleep experts are warning about — with smartphones also causing distractions during the night.
A 2019 study uncoveredthat 36% of teens and 26% of adults wake up to check their mobile device at least once during the night, with the survey’s director of research describing the “disruption” of sleep as a “legitimate concern.”
Meanwhile, one sleep expert advisedpeople to put down their phones at least three hours before bedtime because “the blue light emitted on your screen can trick your mind into thinking that it’s daytime despite it being dark outside.”