Dr Erin: How does exercise decrease cancer risk?
I had a patient ask me the other day about an article that they read about how people that regularly exercise (walking, running, weight lifting, yoga) have a decreased risk of breast and colon cancer. They were trying to figure out what the connection was between exercising their muscles and cancer cells multiplying.
All of us have cancer cells that pop up in our bodies on a regular basis. When our immune system is functioning well, our body detects these abnormal cells and disposes of them. If our body doesn’t recognize that there is an abnormal cell, it will multiply and turn into cancer.
These abnormal cells become damaged by being exposed to free radicals (radiation, bad chemicals in our diet or environment or from stress on our cells from poor lifestyle choices). When you exercise, your cells become stronger and more resilient to these free radicals and therefore do not mutate as much. Exercise increases our own natural anti-oxidants.
People who exercise also tend to eat more vegetables and fruits, drink less alcohol and smoke less. All of these factors also decrease our exposure to free radicals and reduces our cancer risk. Another side benefit of exercise is that you tend to maintain a healthier weight when you are working out. This helps decrease breast cancer risk specifically because your hormones will be in better balance with a healthy weight!
For most of my patients, I suggest participating in moderate cardiovascular exercise 3 times a week for at least 30 minutes per session (walking, jogging, runnning, biking, swimming, dance). In addition, doing strength training 2 times a week for at least 30 minutes per session helps decrease your osteoporosis risk and also helps you manage your weight better. Strength training could be yoga, pilates, free weights, circuit training or traditional weight lifting.