We've all heard assertions that television viewing is an instrument of the devil. Sex, violence, alcohol use and smoking all figure prominently and may influence choices people make in their lives that result in harmful outcomes. But now a meta-analysis Rick and I discuss in this week's podcast quantifies the health risk of the simple act of watching TV. That's in the current issue of the Journal of the American Medical Association.
8 studies were included in this analysis, and together represented some rather large numbers of people: for diabetes risk over 175,000, for cardiovascular disease almost 35,000, and for all cause mortality over 26,000. Data were crunched for 2 hours of television viewing per day, and found that that level of TV watching increased risk of diabetes by 20%, cardiovascular disease by 15% and the risk of dying of any cause (so-called 'all cause mortality') by 13%.
Additional sobering statistics were also included in this analysis. First of all, 2 hours of television viewing is quite modest in comparison to many national norms. In Australia and in several European countries, 3.5 to 4 hours per day is typical, while the average US resident logs in 5 hours per day! As Rick reveals in the podcast, we're incredulous that people have that much time to spend watching TV daily. What's even more distressing is that this study reveals a linear relationship between hours spent watching and disease and death risk, so the more you watch, the higher your risk. Clearly, extrapolating the curve would reveal higher risks than those quoted here.
Why is it that TV viewing is so harmful? Obviously, hours spent watching TV are sedentary, and reduce available time to engage in more vigorous activity. When people are watching television they also consume more fried foods, processed meats and sugar-sweetened beverages, and correspondingly less fresh fruits and vegetables and whole grains. This behavior is likely promoted by the advertisements seen on TV.
The authors admit that sedentary behavior in general has been shown in multiple studies to be deleterious to health. People who sit at desks all day or drive trucks long distances experience some of the same negative consequences of relative inactivity seen in this study. My own view of the matter is this: our anatomy is designed for movement, and our physiology designed for a varied diet singularly lacking in processed foods. When we ignore our design needs we do so at the consequence of our health, and that's no surprise. The solution is also simple and so obvious I won't state it here.
Other topics this week include malpractice in inpatient and outpatient settings and the negative consequences of ambulance drive-bys, also in JAMA, and parental attitudes toward having their children vaccinated in the journal Health Affairs, a first for us! Until next week, y'all live well.
TV, Disease and Death,1 Comment