Having a sedentary lifestyle is bad for your health because it can increase your risk of chronic conditions such as obesity, diabetes and cardiovascular disease.
If you don’t exercise regularly, it’s not too late to change your habits. According to a study published in the journal JAMA Internal Medicine, exercise offers benefits beyond improving your physical health.
The study authors found compelling evidence that exercising regularly can help reduce the risk of many types of cancer.
The review supports physical activity as a means of cancer prevention, with experts suggesting that exercise can be used to help manage cancer treatment-associated symptoms and side effects.
Cancer prevention through regular exercise and body weight regulation
To understand the link between regular exercise and cancer prevention, researchers analyzed the underlying mechanisms that contribute to this relationship.
One key mechanism involves the regulation of body weight and, specifically, body fat. Regular exercise can help you maintain a healthy body weight and lowers your risk of developing excess body fat.
In the JAMA study, Steven C. Moore of the National Cancer Institute and other researchers gathered data from 12 U.S. and European cohorts who self-reported their physical activity from 1987 to 2004. The research team then studied the link between physical activity and the incidence of 26 kinds of cancer.
The study, which included 1.4 million participants, reported 186,932 cancer cases during a median of 11 years of follow-up.
The researchers found that high levels of physical activity among the participants were associated with lower risks of 13 out of 26 cancers, namely:
- Esophageal adenocarcinoma (42 percent lower risk)
- Liver cancer (27 percent lower risk)
- Lung cancer (26 percent lower risk)
- Kidney cancer (23 percent lower risk)
- Gastric cancer (22 percent lower risk)
- Endometrial cancer (21 percent lower risk)
- Myeloid leukemia (20 percent lower risk)
- Myeloma (17 percent lower risk)
- Colon cancer (16 percent lower risk)
- Head and neck cancer (15 percent lower risk)
- Rectal cancer (13 percent lower risk)
- Bladder cancer (13 percent lower risk)
- Breast cancer (10 percent lower risk)
Most of the associations remained regardless of a person’s body size or smoking history.
The research team reported that overall, a higher level of physical activity is associated with a seven percent lower risk of total cancer. (Related: Positive lifestyle changes can help reduce cancer risk and boost the overall health of cancer survivors.)
Regularly engaging in physical activities like walking, jogging, cycling or some forms of resistance training, such as weight lifting or bodyweight exercises, can help lower your cancer risk.
How exercise affects hormone levels and immunity
Exercise is important for cancer prevention because it influences hormone levels, another crucial factor in cancer development.
Studies have found that physical activity can decrease circulating levels of estrogen. Excess estrogen has been linked to a greater risk of breast and endometrial cancers.
Physical activity can also help improve insulin sensitivity by reducing insulin and insulin-like growth factor levels, which are known to promote the growth of certain cancer cells.
Additionally, regular exercise can boost your immune system’s ability to detect and destroy cancer cells. Exercise boosts the production and activity of immune cells, including natural killer cells, which have a crucial role in recognizing and eliminating cancer cells in the body.
