Early stages of colorectal cancer may produce no warning signs or may include:

• Having diarrhea or constipation
• Feeling that your bowel does not empty completely
• Finding blood (either bright red or very dark) in your stool
• Finding your stools are narrower than usual
• Frequently having gas pains or cramps, or feeling full or bloated
• Losing weight with no known reason
• Feeling very tired all the time
• Developing anemia
• Having nausea or vomiting

Most often, these symptoms are not due to cancer. Other health problems can cause the same symptoms. Anyone with these symptoms should see a doctor to be diagnosed and treated as soon as possible.

Colorectal cancer is the fourth most common cancer and the second highest cause of cancer-related deaths. Risk factors of colorectal cancer include:

• Age over 50. Colorectal cancer is more likely to occur as people get older.
• Colorectal polyps. Polyps are growths on the inner wall of the colon or rectum. Most polyps are benign (not cancer), but finding and removing polyps may reduce the risk of colorectal cancer.
• Family history of colorectal cancer
• Personal history of cancer
• Ulcerative colitis or Crohn’s disease
• Diet high in animal fat and low in calcium, folate and fiber
• Heavy alcohol consumption
• Cigarette smoking

Colorectal cancer can be difficult to detect and usually does not cause pain in its early stages. The National Cancer Institute recommends a colonoscopy beginning at age 50 and repeated at regular intervals according to each individual’s risk factors.