People who spend two hours or more a day in front of a screen during their leisure time — primarily watching television — have more than double the risk of cardiovascular events over four years compared with those who spend less than two hours a day in front of a screen
Source: Stamatakis E, Hamer M, Dunstan DW et al. Screen based entertainment time, all-cause mortality, and cardiovascular events. Population based study with ongoing mortality and hospital events follow-up. J Am Coll Cardiol 2011; 57: 292-299.