*Smoking. People who smoke cigarettes may have an increased risk of colon cancer.
*Alcohol. Heavy use of alcohol may increase your risk of colon cancer.
*Processed and red meats may increase your risk of rectum and colon cancer.
*Radiation therapy for cancer. Radiation therapy directed at the abdomen to treat previous cancers may increase the risk of colon cancer.
* Inflammatory intestinal conditions. Chronic inflammatory diseases of the colon, such as ulcerative colitis and Crohn's disease, can increase your risk of colon cancer.