Get off your bum: Sitting, watching TV for two or more hours per day raises risk of colorectal cancer

Living a sedentary life may cause more harm to your health than you think. A study published in JNCI Cancer Spectrum found that sitting and watching television for at least two hours may increase your risk of colorectal cancer before you reach age 50.

The number of people diagnosed with colorectal cancer before age 50 continues to increase in the U.S., and globally. Colorectal cancer in younger people is typically more aggressive and found at a more advanced stage than those in older people, which results in greater years of life lost.

For the study, researchers from Harvard Medical School and Washington University School of Medicine (WUSM) looked at the sedentary TV reviewing time and other sedentary behaviors in 89,278 women from the U.S. who were enrolled in the Nurses’ Health Study II. Over two decades of follow up, the researchers recorded 118 cases of young-onset colorectal cancer. Out of the 118 cases, watching TV every day for more than an hour was linked to a 12 percent increase in risk compared to those who watched less.

The results were even more pronounced in those who spent over two hours watching TV every day. The researchers found that those who watched TV for more than two hours daily had almost 70 percent increase in colorectal cancer risk. This association was independent of body mass index and exercise, which indicated that being sedentary may be an entirely distinct risk factor for young-onset colorectal cancer. Moreover, it was consistently seen among women without a family history of colorectal cancer. In addition, the link was also striking for rectal cancer compared to colon cancer. The findings of the study also reported that women who watched more TV were often postmenopausal, smoked more cigarettes, used aspirin more often, were more physically inactive, had generally poorer diets, and had a higher rate of diabetes.

The researchers did not find a clear link between increased risk in colorectal cancer and other forms of sitting at home, including mealtime or time spent at a desk. On the contrary, those with a lower risk of colorectal cancer reported more active behaviors, such as standing or walking at work or home.

“This study may help identify those at high risk and who might benefit more from early screening,” said Yin Cao, assistant professor of Surgery at WUSM, and the co-senior author of the study.

The study is one of the first to associate certain sedentary behavioral patterns with the risk of early-onset colorectal cancer. (Related: Sitting for long periods of time raises cancer risk by 66 percent.)

Spending too much time sitting in front of the TV may be deadly

Researchers at the Baker Heart and Diabetes Institute in Australia revealed in an earlier study that too much sitting in front of the TV daily may increase the risk of death from heart disease and other causes, even in people who are not overweight.

Particularly, they found that spending at least four hours sitting in front of the TV each day can increase the risk of death from all causes by 46 percent and the risk of cardiovascular death by 80 percent. For each hour, an individual’s risk of death from cardiovascular disease increased by 18 percent and the risk of death due to cancer raised by nine percent.

Published in the journal Circulation, the study looked at about 9,000 Australian adults who were about age 50. They were tracked for about six years.

Get moving and prevent the onset of many diseases caused by a sedentary lifestyle. Learn more at FightObesity.news.

Sources include:

EurekaAlert.org

DailyMail.co.uk

Reuters.com