Most people know staying active improves overall health. Specifically, exercise and physical activity have been shown to decrease risk for two leading causes of death in the United States – heart disease and cancer.
Whether you choose to regularly exercise or do simple things like taking the stairs at work, getting off the couch, or using a walking lawn mower, various studies have shown physical activity helps reduce cancer risk and can even decrease risk of recurrence if you’ve had cancer previously.
Certain cancers have been studied more than others. Breast, colon and endometrial cancers are the most documented. Physical activity can reduce risk of colon and breast cancer by about 25 to 30 percent. Pancreatic and prostate cancers also have been studied and physical activity has been shown to decrease their risk as well.
You don’t have to run a marathon
Dr. Isaac Yeboah, a Marshfield Clinic oncologist, says there’s a difference between exercise and physical activity, but both help reduce the risk of cancer. Either way your risk increases if you have a sedentary lifestyle.
“When you think of exercise, you think of a regimented workout plan,” he said. “Physical activity on the other hand involves any movement of your muscles and joints. This can include walking up and down the stairs instead of using the elevator, taking a walk in your neighborhood, bicycling, dancing and yardwork among others. These studies show both exercise and physical activity help reduce cancer.”
Dr. Yeboah says this physical activity doesn’t mean you have to lose weight either. An obese person who is physically active can still have the benefit of decreasing cancer risk without necessarily losing weight.
“Of course obesity has its associated risks, but if you’re not sitting behind a TV for eight hours a day, you still get the benefit of a decreased risk of cancer,” Dr. Yeboah said. “Certainly you have to take into account the fact that it can cause heart disease, diabetes, etc., but physical activity doesn’t have to be connected with losing weight.”
How does physical activity reduce cancer?
A number of theories have been postulated. First, activity increases certain hormone levels. Levels of insulin growth factor one, a protein found in the body, adjusts with physical activity. This helps decrease the stimulation of cells that promote cancer development.
Estrogen levels play a role.
“Estrogen increases the risk of breast and endometrial cancer,” Dr. Yeboah said. “Activity influences the hormone level. So if you decrease estrogen levels, you decrease the chance of cancer development.”
Physical activity also affects inflammatory markers. These are antibodies the body can create that can attack it. When these levels are high, cancer risk increases, but physical activity can reduce the level of markers.
Activity helps not only to reduce the risk of developing cancer, but also is helpful for someone going through active cancer treatment.
“The great thing about activity is that it decreases your level of fatigue,” Dr. Yeboah said. “It gives patients the ability to handle treatments like chemotherapy better if they’re not tired. This can improve the outcome of their treatment.”
People have to stay active, said Dr. Yeboah.
“Stay off the couch and walk around. Staying active all day is the most important message we’re trying to get across, and this does not have to involve weight lifting or running a marathon,” he said. “Keep it simple.”