Exercise cuts bowel cancer risk

GINA RAVENSCROFT, SCIENCENETWORK WA

The study confirms that the most physically active have a lower risk of bowel cancer than the least active. Image: mediaphotos/iStockphoto Researchers at the University of Western Australia (UWA) and the Western Australian Institute for Medical Research (WAIMR) have found people who engage in vigorous physical activity may be protected against types of colorectal cancer. The study, published in the Cancer Causes Control journal, used a Western Australian cohort.  Researchers examined 870 participants who had bowel cancer and a control group of 996 who did not have the disease. Study participants were asked to answer questions about their recreational physical activity, lifestyle, diet, medication and occupation. UWA PhD student Terry Boyle, also supported by the Lions Cancer Institute, says the study confirms previous research that shows the most physically active have a lower risk of bowel cancer than the least active.  “It also gives us some clues as to what types of activity are the most effective at reducing bowel cancer risk,” Mr Boyle says.  The study found people who performed regular vigorous physical activity over their lifetime had a 40 per cent reduced risk of cancer of the distal (lower) colon and rectum. “These results suggest that vigorous activity like jogging, cycling, swimming, tennis, hockey, netball and football may be the most effective physical activities to lower the risk of bowel cancer,” Mr Boyle says. Of the possible mechanisms linking physical activity and colon cancer, there is evidence to suggest that obesity and vitamin D may have a great effect on distal colon cancer than proximal colon cancer. While the link between physical activity and colon cancers remains opaque, this study supports the suggestion that lifestyle factors are more strongly tied to distal colon cancer than proximal colon cancer.   Another finding showed physical activity performed after the age of 51 years, may be more beneficial in reducing the risk of distal colon cancer than physical activity performed earlier in life. “This shows that it really is never too late to start being physically active,” Mr Boyle says. Editor's Note: Original news release can be found here.