Reducing Your Risk of Cancer

By Leslie Robison, Ph.D.

Those who are diagnosed with cancer often ask, "Why me? What could have caused this?" While research has provided important insights into genetic and environmental factors that may contribute to the development of some cancers, in most cases the cause of many cancers remains unknown.

To help solve this mystery, researchers have been working to better understand and to identify risk factors that increase a person's chance of developing cancer. Some risk factors cannot be changed (such as a person's age, sex, and family history of the disease), while others can (such as tobacco use, diet, and sun exposure). The American Cancer Society (ACS) estimates that out of the more than one million new diagnoses of cancer each year, about one-third are due to dietary factors and another third are due to tobacco use.

It is important to note that having a risk factor for cancer means that a person is more likely to develop the disease at some point in their lives than someone who does not have a risk factor. However, having a risk factor does not guarantee that a person will develop cancer. Some people with one or more risk factors never develop the disease, while other people who do develop cancer have no obvious risk factors.

There is no sure way to avoid getting cancer, but there are steps you can take to reduce your risk. Some general recommendations include:eat five or more servings of fruits and vegetables each day and limit your intake of high-fat foods and alcoholic beverages,be physically active for 30 minutes or more four to five days a week, and avoid all tobacco products.

According to the ACS, dietary choices and physical activity become the most important modifiable cancer risk factors for the large majority of Americans who do not smoke cigarettes. For example, adding more fruits and vegetables to your daily diet can greatly reduce your risk of cancer. Certain vegetables and fruits, such as cauliflower, lettuce, oranges and lemons, have certain "ingredients" that break down and fight off carcinogens (cancer-causing substances).

Research has shown that people who regularly exercise have a lower risk of developing certain types of cancer, primarily colon cancer. My colleague, Kathryn Schmitz, Ph.D., is currently looking at the effect physical activity has on the risk of breast cancer recurrence in female breast cancer survivors. Previous research conducted by Schmitz is encouraging in that most women who regularly performed strength-training exercises twice a week had a lower level of a growth factor associated with breast cancer risk.

Finally, the single most important thing you can do to reduce your risk of developing cancer is to not smoke or use tobacco products. Using tobacco products yourself significantly increases your risk of developing a broad spectrum of cancers (specifically lung, mouth, pharynx, larynx, esophagus, pancreas, uterine, cervix, kidney, and bladder). Research now shows that non-smokers who are exposed to tobacco smoke on a regular basis also have an increased cancer risk. Many researchers are currently working on ways to reduce tobacco-related cancer risk, including evaluating strategies to help people quit using tobacco products and identifying the specific substances in tobacco that lead to addiction.