Researchers at Harvard have found that an active lifestyle with limiting TV time could prevent obesity and type 2 diabetes. In a survey conducted in the US TV watching results in a lower metabolic rate when compared to activities like sewing, playing board games, reading, writing or driving a car. Prolonged TV watching is also linked to obesity in children. The health campaigns are focussed on increasing exercise and hardly concentrate on reducing sedentary behaviours.
In a study conducted for over six years researchers have found that time spent watching TV was positively associated with risk of obesity and type 2 diabetes. The researchers estimated that 30 percent of new cases of obesity and 43 percent of new cases of diabetes could have been prevented by adopting a relatively active lifestyle of less than 10 hours per week of TV-watching and 30 minutes or more per day of brisk walking. TV-watching typically displaces physical activity and reduces the amount of time used to burn energy. People tend to eat while watching TV despite their low physical activity levels, resulting in increased food and total energy intake. TV watching burns less energy compared to other sedentary activities like sewing, reading, writing, and driving a car.