Colorectal Cancer: Are You at Risk?

Don’t just take your chances: take steps to reduce your risk for this common cancer.

According to the National Cancer Institute, colorectal cancer is the fourth most common cancer in the United States, where an estimated 145,600 new cases were diagnosed in 2019. Fortunately, increasing awareness of the risk factors has led more people to receive screenings, which can detect cancer early and even stop it before it starts.

What Causes Colorectal Cancer?

Almost all colorectal cancers begin in small growths called polyps. According to the American College of Gastroenterology, most polyps are harmless. The few that are problematic grow slowly, taking about 10 years to become cancerous.

Risk Factors for Colorectal Cancer

Colorectal cancer risk is influenced by many factors. Some are unavoidable, but others can be changed. Risk factors for colorectal cancer that cannot be changed include:

  • Age. According to the Colon Cancer Coalition, more than 90% of cases occur in people over age 50.
  • Family history of colorectal cancer
  • Hereditary syndromes linked with colorectal cancer, such as hereditary nonpolyposis colon cancer or familial adenomatous polyposis
  • Personal history of colorectal cancer, some types of polyps, or inflammatory bowel disease
  • Previous abdominal or pelvic radiation to treat a previous cancer

However, you can lower your risk for colorectal cancer by making the following healthy changes:

  • Eat a healthy diet, low in red and processed meats and high in fiber, fruits and vegetables.
  • Exercise regularly. Physical activity helps lower your risk.
  • Lose weight. Being overweight or obese raises the risk of colorectal cancer in both men and women.

Screening Guidelines

The American Cancer Society (ACS) recommends that people at average risk for colorectal cancer begin screening at age 45. People at increased risk may need to begin testing at a younger age or have tests more frequently.

The most accurate colorectal cancer screening tests involve visually inspecting the intestines. The ACS recommends that these tests be repeated regularly until age 75: colonoscopy every 10 years, CT colonography every five years or flexible sigmoidoscopy every five years.