Risk factors may include:

• age
  Most people who have colorectal cancer are over age 50, however, it can occur at any age.
• diet
  Colorectal cancer is often associated with a diet high in fat and calories, and low in fiber.
• polyps
  Benign growths on the wall of the colon or rectum are common in people over age 50, and are believed to lead to colorectal cancer.
• personal history
  People who have had colorectal cancer, as well as ovarian, uterine, or breast cancers, have a slightly increased risk for colorectal cancer.
• family history
  People with a strong family history of colorectal cancer or polyps in a first-degree relative (in a parent or sibling before the age of 60 or in two first-degree relatives of any age), have an increased risk for colorectal cancer.
• ulcerative colitis
  People who have ulcerative colitis, an inflamed lining of the colon, have an increased risk for colorectal cancer.
• obesity
• physical inactivity
• high-fat and/or low-fiber diet
• alcohol consumption
• diabetes