Dr. Thomson shares if life-long athletes have an increased cancer risk caused by oxidative stress.
Lifelong athletes certainly do expose their bodies to a certain higher level of oxidative stress. We know that activity induces oxidative stress at a certain level. I mean, you have to push a little. Some people think activity is walking to get the mail and that is not going to be problematic. And in fact, we do see kind of a U-shaped curve with physical activity when we look at the epidemiological data.
In other words, people who are at the low end and people at the very ultra high end are going to be at increased risk, generally. That said, we do not have a lot of evidence from, say, marathon runners. We don’t have a cohort of, you know, 50,000 marathon runners that we have been following for 25-30 years to find out.
What I would say is that while it is true excess activity can be a stress to the body, those people are also the people who are more likely to eat a healthy diet, not smoke, and perhaps even take dietary supplements that are antioxidants. So they have kind of a buffer from other lifestyle practices.
In addition, I in no way want to send a message that people should be cautious of physical activity because let’s face it–95 plus percent of Americans are not active enough, and so the last thing we want to do is for people to rationalize their inactivity based on the fact that activity increases oxidative stress. What’s important is to get active and while you are active, increase your intake of these bioactive food compounds that act as antioxidants.
About Dr. Thomson, Ph.D., R.D.:
Dr. Cynthia Thomson, Ph.D., R.D., is an Associate Professor in the Department of Nutritional Sciences at the University of Arizona. She is a registered dietitian with a doctoral degree in nutritional sciences. She has been conducting cancer research since 1994. Dr. Thomson was diagnosed with colorectal cancer in 2003.