Watching TV can be hazardous to your health. In a study of more than 50,000 women, every two hours per day of TV watching increased the risk of obesity by 23% and the risk of diabetes by 14%. Sitting while at work was linked to much smaller increases in risk.
In contrast, ever hour per day of brisk walking was linked to a 24% drop in risk of obesity and a 34% drop in the risk of diabetes. An estimated 30% of new cases of obesity and 43% of new cases of diabetes could be prevented if women were to spend less than 10 hours a week watching TV and at least 30 minutes a day walking briskly, say the authors.
(Source: Nutrition Action Health Letter, June 2003, Volume 30/Number 5.)