Environmental exposures and cancer risk
Most people think of forests, parks or even city streets when they hear the word “environment,” but scientists define environment as everything outside the body that enters and interacts with the inside of the body. Some of these outside exposures have been linked to increased cancer risk.
According to the National Cancer Institute, researchers have estimated that as many as two in three cases of cancer are linked to some type of environmental factor, including tobacco, alcohol, food, radiation, infectious agents and pollution. The good news is that many environmental factors that are linked to an increased cancer risk can be reduced through lifestyle choices.
The following are examples of common environmental risk factors that can be reduced with behavior modification:
Some chemicals that were banned decades ago, such as certain insecticides, are still persistent in the environment and can accumulate in the human body. You can reduce your exposure by:
- Eating a healthy diet that is rich in fruits, vegetables and whole grains and, when possible, buying organic. Avoid processed meats and limit your intake of red meat, and farm-raised fish, including salmon, which can all contain high levels of chemicals.
- Consuming plenty of filtered or spring water and avoiding storing water in plastic containers. Also, do not expose plastic food or water containers to high heat in the microwave or dishwasher.
- Getting regular exercise (150 minutes of moderate intensity or 75 minutes of vigorous intensity per week) in places with low levels of air pollution. Avoid walking, running or biking in high traffic areas, such as during rush hour, when air pollution is at its peak.
Tobacco and alcohol
Smoking is the most important risk factor for cancers. Alcohol is another risk factor, with heavy drinkers increasing their risk of mouth, throat, liver, esophageal and breast cancer. To reduce your cancer risk:
- Don’t use tobacco products and limit your exposure to secondhand smoke.
- Drink alcohol in moderation, which is no more than one or two drinks per day.
Excessive sunlight exposure
Ultraviolet (UV) radiation is an important environmental risk factor for skin cancers. Avoid excessive UV exposure by:
- Applying sunscreen.
- Limiting sun exposure.
- Wearing protective clothing.
There are other environmental cancer risks that can be reduced. Occupational and household exposures, such as radon and asbestos, have been linked to certain cancers. Some cancer treatments, such as chemotherapy and radiation therapy, may increase risk of developing a different type of cancer later in life.
For more information on environmental cancer risks, visit cancer.gov/cancertopics/causes.
About the author
David C. Wheeler, M.P.H., Ph.D., is a member of the Cancer Prevention and Control research program at VCU Massey Cancer Center and assistant professor of biostatistics at VCU School of Medicine.