Although colorectal cancer is one of the most common types of cancer in the United States, scientists are trying to learn more about what causes the disease and how it can be prevented.

Doctors do not yet know why one person gets colorectal cancer and another does not, but they do know that no one can catch colorectal cancer from another person. Cancer is not contagious.

People can lower their risk of getting colorectal cancer. For example, those who have colorectal polyps (nodular growths of tissue developing in the lining of a cavity, which may be benign or malignant), should talk with the doctor about having them removed. People can also change their eating habits to cut down on fat and increase the amount of fiber (roughage) in their diet.