A study from the International Agency for Research on Cancer in France found that men who watched more than four hours of TV per day were likelier to develop colorectal cancer than those who watched less.
The study on colorectal cancer and TV
The evidence it’s really surprising, considering that a lack of physical activity has been linked to a higher risk for colorectal cancer.
In addition, the lead researcher, Dr. Neil Murphy, points out that excessive time in front of the TV is equated with obesity. “Being sedentary is also associated with weight gain and greater body fat,” he explains. “Excess body fat may influence the blood levels of hormones and other chemicals which affect the way our cells grow and can increase bowel cancer risk.”
The study analyzed data from UK Biobank, a health database of nearly 500,000 people based in the UK. They looked at how much time was spent in front of a computer or watching TV.
After six years, 2,391 cases of colorectal cancer were identified. The researchers found that compared to men who watched TV for only up to one hour daily, those who watched TV for at least four hours daily had a 35% greater risk of colorectal cancer.
Interesting, there was no link for women or for men who sat in front of a computer. So, why didn’t sedentary time in front of a computer affect men too? The researchers theorize that it has to do with more advertisements for junk food.
The good news
Men who engaged in higher levels of physical activity had a 23% lower risk of developing colon cancer compared to those who didn’t engage in much activity.
And why the good news for women, who didn’t show an increased risk of cancer despite watching four or more hours of TV?
“The study didn’t look at this directly, but it could be because men might smoke, drink and eat more unhealthily than women while watching TV,” explains Professor Linda Bauld, a cancer prevention expert at Cancer Research UK. “What we do know is that keeping a healthy weight, cutting back on alcohol, being physically active and eating a diet rich in fruits and vegetables are known to cut your risk of bowel cancer.”
