Exercise cuts colon cancer risk by a quarter

Feb 11 2009

Engaging in physical activity can reduce your chances of developing the most common kind of bowel cancer by a quarter, according to new research published in the British Journal of Cancer.

A team of US scientists reviewed the results of 52 previous studies on exercise and colon cancer risk to make the most comprehensive calculation yet of the effect that physical activity has on both men and womens risk of developing colon cancer.

Overall, they found that the most active people are 24 per cent less likely to develop the disease than the least active people. Colon cancer is the most common form of bowel cancer, which is the third most common form of cancer, affecting more than 36,500 people a year in the UK.

The study took into account many different types of physical activity including occupational activity like manual labour, as well as more traditional leisure-time activity such as running or going to the gym. These studies used different methods to quantify the amounts of exercise people took. One study for instance considered the most active people to be those who walked briskly for five to six hours a week in comparison to those who walked for 30 minutes a week or less.

Study author, Dr Kathleen Wolin, from the'Washington University School of Medicine in St. Louis said: "These results give us a very reliable calculation of the positive effect that exercise can have on reducing colon cancer risk. It's very positive to see that exercise has such a clear benefit in reducing cancer risk and we hope it will encourage people to enjoy a healthy active lifestyle as well as treating it as a way to minimise their colon cancer risk.

"Once future studies have been done, we would like to go on and personalise these results further, taking into account the impact factors such as racial origin, weight and diet have on bowel cancer risk, so that we can make individual recommendations on how people can reduce their chances of getting the disease."

Sara Hiom, director of health information at Cancer Research UK, said: "One hundred people a day are diagnosed with bowel cancer in the UK alone, so it's imperative that we do all we can to prevent the disease. This work brings together the findings from many different studies which seek to understand the affect that exercise has on cancer risk - which gives us greater confidence in its results.

"We know that around half of all cancers could be prevented by changes to lifestyle. Maintaining a healthy bodyweight is one of the best ways to lower the risk of bowel and other cancers - potentially helping to avoid an estimated 13,000 cases each year. Cancer Research UK recommends that you try to take half an hour's physical activity a day, five days a week. This should be enough to leave you feeling warm and slightly out of breath and can include housework or walking briskly."