Reduce Risk of Cancer with Exercise
Millions of dollars each year are devoted to developing cancer-fighting drugs. While drugs that prevent all cancers still elude us, there is one natural “drug” – physical activity – that has been shown to reduce your risk for cancer.
“Physical activity is a wonder drug of sorts,” says Michael A. Hunter, MD, a radiation oncologist at the Halvorson Cancer Center at EvergreenHealth. “Studies have proven there’s a direct tie between exercise and cancer reduction.”
Researchers report that exercise, such as walking, reduces a person’s risk for cancer.
In particular, the study found that postmenopausal women who participated in vigorous physical activity every day had a 25 percent lower risk for breast cancer, and women who walked at least seven hours a week had a 14 percent lower risk.
Research has also found exercise lowers the risk for other cancers:
- Prostate Cancer: Working out can lower the chance of developing prostate cancer in Caucasian males.
- Colorectal and Lung Cancer: Middle-aged men who engage in a lot of cardiovascular exercise reduce their risk of suffering lung and colorectal cancer.
- Uterine Cancer: There's a 38 to 46 percent reduced risk of uterine cancer in active women. Exercise lowers obesity and decreases estrogen levels, both of which are related to uterine cancer development.
Physical activity positively impacts the body in several ways, including preventing obesity, reducing inflammation and hormone levels, and improving insulin resistance and immune system function.
All of these benefits, individually and collectively, lower a person’s risk for cancer and other diseases.
A weighty risk
One of the most significant ways exercise lowers cancer risk is through weight control.
According to cancer.gov, obesity increases a person's risk of developing and dying from many types of cancer, including:
- postmenopausal breast cancer
- colorectal cancer
- uterine cancer
- kidney cancer
- pancreatic cancer
- gallbladder cancer
- thyroid cancer
- esophageal cancer
It’s been linked to many others, including prostate cancer, liver cancer, ovarian cancer, cervical cancer, multiple myeloma and non-Hodgkin's lymphoma.
There are many reasons obesity increases cancer risk.
“In overweight, post-menopausal women, for example, fat cells produce excess estrogen,” says Dr. Hunter. “High levels of estrogen are associated with the risk of several cancers, including both breast and endometrial.”
Obesity often leads to chronic low-level inflammation as well as increased levels of insulin in the blood—both of which can increase the risk of certain tumor growth.
Dr. Hunter says body mass index (BMI) — the ratio of a person’s height and weight — is one good measure to determine if you are at an increased risk for cancer.
“The most optimal BMI range is 20 to 25,” says Dr. Hunter. “I tell my patients they don’t need to join a gym to get within that BMI range. You can walk, take the stairs, dance, or any other activity that you can do right in your home or neighborhood.”
For substantial health benefits, Dr. Hunter recommends striving for 150 minutes a week of moderate aerobic activity or 75 minutes a week of vigorous aerobic physical activity — or a combination of both.
There’s no “one size fits all” approach to exercising. “If you’re social, find a group activity, like aerobics. If you like exercising on your own, you may enjoy something that provides more reflective time, like yoga or walking,” Dr. Hunter says. “The goal is to find something that works for you and to stick to it.”