It is a new year and how many of us made a resolution to exercise and adopt a healthier lifestyle? We know that exercise will reduce your risk for cancer, heart disease, hypertension, and frankly, premature death. There have been a few studies that looked at what happens if you not only don’t exercise but actually sit around too much, which is different from not exercising. In this week’s issue of the journal Circulation is an interesting study from Australia that looks at television viewing time and mortality.
Many studies have reported that television viewing time is associated with weight gain, type 2 diabetes, cancer, abnormal sugar metabolism, metabolic syndrome and other cardiovascular risk factors. There has even been a kind of dose-response association; in other words, we see worse outcomes if you watch more than four hours a day compared to two hours a day. In this study, Australian researchers followed the lifestyle habits of some 8,800 adults and looked at total cardiovascular disease, cancer and other causes of mortality. In the study, close to 4,000 men and close to 5,000 women 25 and older were interviewed and underwent several tests including sugar challenge testing and blood to examine cholesterol and other markers
The researchers found for every hour spent in front of the television daily there was:
- 11% increased risk of death from all causes
- 8% increase risk of cancer death
- 18% increase risk of cardiovascular disease-related death
For those who watched more than four hours a day (compared to those who watched less than two hours a day) there was a 46% higher risk of death from all causes and an 80% increased risk for death for cardiovascular disease-related deaths. When the researchers controlled for smoking, high BP, High cholesterol, unhealthy diet, excessive waist circumference and leisure time exercises, the association still held true! There is no reason to believe that the findings would not be the same if it was excessive computer time one was looking at. When you sit, you are not expending any energy that occurs with getting up and moving around. Your muscles are not being used as well. What is really important to understand is that these findings apply to people with healthy weights as well as those who are overweight and obese.
Average daily television watching is as high as 8 hours a day in the United States. The average adult Canadian watched almost 1,500 hours of television and an estimated 25,000 television commercials in 2008 based according to research by Digital Home Canada. The study started in 1999 and followed through 2006. The researchers noted that the association between cancer mortality and television viewing was modest but the direct association between the amount of television watched and elevated cardiovascular death as well as death from all causes was impressive.
So as you start this new year, remember that not only should you be exercising more but you should be watching less television!