Too Much TV Increases Risk of Diabetes, Cardiovascular Disease
If you spend 2 to 3 hours or more watching TV every day, you may increase your risk of diabetes, cardiovascular disease, and dying from any cause, according to a new study appearing in the Journal of the American Medical Association. This is frightening news, given that the average TV viewing time in the United States is 5 hours daily.
Watching too much TV can be deadly
Watching TV is one of the top three common activities many people participate in around the world (the other two are sleeping and working), and it is also associated by unhealthy eating habits and being physically inactive. Poor eating and inactivity, along with smoking, are all significant risk factors for type 2 diabetes, cardiovascular disease, and death.
Given the high prevalence and potentially unhealthy effects of TV watching, Anders Grontved, MPH, MSc, of the University of Southern Denmark, and Frank B. Hu, MD, PhD, of Harvard School of Public Health, conducted a meta-analysis to quantify “its independent association with health outcomes.”
The analysis included eight studies from 1970 to March 2011, several of which offered information in more than one category: four provided results on type 2 diabetes (175,938 subjects), four provided data on fatal or nonfatal cardiovascular disease (34,253 subjects), and three reported information on all-cause mortality (26,509 subjects).
After evaluating the data, the investigators found that watching 2 hours of TV per day was associated with a 20 percent greater risk for type 2 diabetes, a 15 percent increased risk for fatal or nonfatal cardiovascular disease, and a 13 percent greater risk for death from all causes.
Not all the findings were equal, however. The authors also noted that “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.”
Some previous research has indicated that prolonged TV time is associated with obesity, unhealthy lipid levels, risk of diabetes, and cardiovascular risks, although not all studies have reported these associations. In addition, some randomized controlled studies have shown that reducing the amount of TV viewing time led to slowed increases or reductions in body mass index.
The authors concluded that their findings indicate too much TV—2 or 3 hours or longer—“is consistently associated with higher risk of type 2 diabetes, fatal or nonfatal cardiovascular disease, and all-cause mortality.” Additional research is necessary to identify whether reducing TV time can help prevent these diseases and mortality.
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