Millions of Americans 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. 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.