Get Fit To Reduce Risk Of Cancer
Staying fit and trim may do more than keep your heart healthy, researchers report. It could also reduce your risk of dying from cancer.
In a 25-year study, men who were most fit at the start of the study were less likely to die from cancer. And women who were overweight when the study began were at higher risk of dying from cancer. The results support the current recommendations from the American Cancer Society emphasizing a physically active lifestyle and the prevention of obesity.
Dr.Kelly R.Evenson and her team examined the relationship between fitness and obesity and the risk of dying from all types of cancer.
Evenson, who is at the University of North Carolina at Chapel Hill, said that "It would be nice in future studies if we could examine the relationship of fitness and obesity on certain types of cancers, such as breast cancer."
The study included 2,585 women and 2,890 men who were followed from the early- to mid-1970s to 1998. At the start of the study, volunteers performed a treadmill test to measure their heart health and had their body mass index, or BMI, measured. BMI is a measure of weight in relation to height used to gauge obesity.
After taking into account factors that could influence health, Evenson's team found that the fittest men were about half as likely to die from cancer as less fit men. Fitness levels did not have a significant effect on cancer deaths in women, however.
But a woman's BMI at the start of the study was related to her chances of dying from cancer during the next 25 years, according to the report. Women with the highest BMI were almost 50% more likely to die from cancer than less obese women.
The research team did not examine how fitness and obesity may affect the odds of dying from cancer, but physical activity is believed to reduce cancer risk by influencing levels of certain hormones and growth factors, by decreasing body fat and possibly by enhancing the immune system.