What Keeping Fit Could Do for Your Cancer Risk

Lung and colon cancer risk may decline as fitness levels increase in middle-aged men

(RxWiki News) Physical activity is a vital part of a healthy life. While research has clearly shown its benefits in preventing heart disease, fitness may lower the risk of certain cancers as well.

A new study provides more support for the view of fitness as a cancer fighter. Researchers recently found that a high level of cardiorespiratory activity was linked to a lower risk of lung and colon cancer in middle-aged men. Older men diagnosed with cancer may also lower their death risk if they maintain a high level of fitness.

Past studies have shown that exercise may also curb the risk of colon, breast, uterus, lung and prostate cancer, according to the National Cancer Institute (NCI).

Susan G. Lakoski, MD, of the Vermont Cancer Center at the University of Vermont in Burlington, led this study.

“There is an inverse association between midlife cardiorespiratory fitness [CRF] and incident lung and colorectal cancer but not prostate cancer,” Dr. Lakoski and colleagues wrote. “High midlife CRF is associated with lower risk of [death] in those diagnosed as having cancer at Medicare age [65 or older].”

These researchers studied data on about 14,000 men. Their average age at the start of this study was 49. Patient fitness levels were assessed via a treadmill test between 1971 and 2009.

After an average of 6.5 years, Dr. Lakoski and team found that 1,310 of these patients had developed prostate cancer, 200 had lung cancer and 181 had colorectal cancer (cancer of colon or rectum).

Men who had high levels of fitness had a 55 percent lower risk of lung cancer and a 44 percent lower risk of colorectal cancer than men with low levels of fitness. Exercise did not appear to affect prostate cancer risk.

Among the men who did develop cancer at 65 or older, the risk of cancer-related death was 32 percent lower for those in the high-fitness group than in the low-fitness group.

“Future studies are required to determine the absolute level of CRF necessary to prevent site-specific cancer as well as evaluating the long-term effect of cancer diagnosis and mortality in women,” Dr. Lakoski and team wrote.

This study was published online March 26 in JAMA Oncology.

One author, Dr. Lee W. Jones, was a co-founder of a commercial company, Exercise by Science Inc. Dr. Lakoski received funds from the National Institute of General Medical Sciences. Dr. Jones received research grants from the NCI.

Review Date: 
March 26, 2015