What can I do to reduce my risk of colorectal cancer?

The relationship between exercise and colorectal cancer (CRC) prevention appears clear. Some people, due to unfortunate genetics, will be at high risk for CRC and their options for risk reduction are few. However, risk factors for developing CRC in most of the population are "modifiable." They can be changed or altered if the individual is motivated to do so. Virtually everyone is aware of the impact of diet on the risk of CRC. Some people also know that alcohol and tobacco use can increase the risk of CRC. However, few people realize that physical activity level is also important. Many studies have come to the same conclusion independently. Perhaps the largest was a meta-analysis performed by Australian investigators that included 103 different cohort studies. This massive study showed a clear negative impact of alcohol, tobacco, red meat, diabetes, and obesity. The researchers also confirmed a positive, protective effect of physical activity against the risk of CRC.

A few major studies showed that both occupational and recreational activity levels may be important for CRC risk. Researchers from Norway followed over 60,000 men and women who had undergone screening in the 1970s and found that those with highest occupational and recreational activity levels had the lowest rates of developing CRC. A group from the National Cancer Institute (NCI) showed that light occupational activity was helpful, moderate to heavy activity at work was better, but leisure activity didn't correlate with CRC risk. Lastly, the Nurses' Health Study confirmed the benefit of increased physical activity and leaner body mass index for women to protect against CRC.

According to the American Cancer Society, colorectal cancer is the second leading cause of cancer deaths for men and women combined. Every year in the United States there are approximately 100,000 new cases of colon cancer and 40,000 new cases of rectal cancer. The overall lifetime risk for developing colorectal cancer is about 1 in 19 for men and 1 in 20 for women. The good news…when found early, this type of cancer is highly curable. You can markedly reduce your risk of dying from this type of cancer by changing your lifestyle and getting preventive screening.

Persons with a family history of colorectal cancer, those with a history of polyps in the colon and those over age 50 are at greatest risk for colorectal cancer. Results of a Danish study published in the British Medical Journal in 2010 showed that leading a healthy lifestyle can significantly reduce a person’s risk of colorectal cancer. Here are the healthy lifestyle behaviors that proved beneficial:

• Eating a diet high in fiber, fruits and vegetables and low in red meat
  and processed foods

• Avoiding smoking

• Exercising 30 minutes a day

• Limiting alcohol to seven drinks a week for women and 14 drinks a
  week for men

• Reducing weight

Preventive cancer screening is an important tool to catch precursors to cancer or cancer in it’s earliest stages so that they can be treated successfully. Colorectal cancers often begin as polyps. By removing them, cancer is prevented. Perhaps the easiest and simplest way to screen for cancer is to have your doctor check your stools annually for blood. In addition, beginning at age 50, most people should have a colonoscopy every 10 years to screen for cancer.