Television (TV) viewing is the most commonly reported daily activity apart from working and sleeping in many populations around the world. In the United States, the average number of daily hours of TV viewing has recently been reported to be 5 hours. “Beyond altering energy expenditure by displacing time spent on physical activities, TV viewing is associated with unhealthy eating (e.g., higher intake of fried foods, processed meat, and sugar-sweetened beverages and lower intake of fruits, vegetables, and whole grains) in both children and adults,” according to background information in the article.

“Physical inactivity, various dietary factors, and smoking are well-established independent risk factors of type 2 diabetes, cardiovascular disease, and all-cause mortality. Because TV viewing is the most prevalent and pervasive sedentary behavior, there is a great deal of interest in quantifying its independent association with health outcomes.

An analysis of data indicated that per 2 hours of TV viewing time per day was associated with a 20 percent higher risk for type 2 diabetes; a 15 percent increased risk for fatal or nonfatal cardiovascular disease; and a 13 percent higher risk for all-cause mortality. “While the associations between time spent viewing TV and risk of type 2 diabetes and cardiovascular disease were linear, the risk of all-cause mortality appeared to increase with TV viewing duration of greater than 3 hours per day.