Health library

Reviewed 2/12/2023

Colorectal cancer: True or false?

Researchers don't yet know the exact cause of most colorectal cancer. However, a lot is known about how to prevent, treat and screen for this disease. How much do you know about colorectal cancer?

True or false: Colorectal cancer is not a very common cancer.

False. Every year, about 140,000 people in the U.S. are diagnosed with colorectal cancer. It is the third leading cause of cancer-related deaths in the U.S. Colorectal cancer occurs just as frequently in women as it does in men.

True or false: Colorectal cancer often has no symptoms in its early stages.

True. Most people don't have any signs or symptoms of colorectal cancer. When symptoms do occur, they can include a change in bowel habits; rectal bleeding, dark stools, or blood in the stool; stomach cramps; weakness and fatigue; and weight loss for no reason.

True or false: Eating foods high in fiber may reduce the risk of colorectal cancer.

True. Some studies have shown that eating fiber-rich foods-such as fruits, veggies and whole grains-is associated with a reduced risk for colorectal cancer. However, taking fiber on its own as a supplement does not seem to have this effect. More conclusive research is needed.

True or false: You might increase your risk for colorectal cancer if you eat a lot of processed meat.

True. A diet that's high in processed meat-like hot dogs, ham and sausage-can raise your risk for colorectal cancer. Other things that can raise your risk include smoking, drinking alcohol excessively and being physically inactive.

True or false: Most people who get colorectal cancer have a family history of the disease.

False. Having a family history of colorectal cancer does raise your risk, but most cases are found in people without a family history. Age is one of the biggest risk factors: Most colorectal cancers are found in people age 50 and older. That's why it's so important to start routine colorectal cancer screening when you turn 45.

Ask a doctor about your colorectal cancer risk and screening options. Routine screening for colorectal cancer is crucial to catching the disease early. Colorectal cancer is often very treatable when caught in its early stages-before it has a chance to spread.

Explore screening options

Sources: American Cancer Society; Centers for Disease Control and Prevention; National Cancer Institute; U.S. Preventive Services Task Force; World Health Organization

Sources

American Cancer Society. "American Cancer Society Guideline for Colorectal Cancer Screening." https://www.cancer.org/cancer/colon-rectal-cancer/detection-diagnosis-staging/acs-recommendations.html.

American Cancer Society. "Can Colorectal Cancer Be Prevented?" https://www.cancer.org/cancer/colon-rectal-cancer/causes-risks-prevention/prevention.html.

American Cancer Society. "Colorectal Cancer Risk Factors." https://www.cancer.org/cancer/colon-rectal-cancer/causes-risks-prevention/risk-factors.html.

American Cancer Society. "Key Statistics for Colorectal Cancer." https://www.cancer.org/cancer/colon-rectal-cancer/about/key-statistics.html.

American Cancer Society. "Take the Quiz: Colorectal Cancer." https://www.cancer.org/cancer/colon-rectal-cancer/colorectal-cancer-quiz.html.

American Cancer Society. "What Causes Colorectal Cancer?" https://www.cancer.org/cancer/colon-rectal-cancer/causes-risks-prevention/what-causes.html.

Centers for Disease Control and Prevention. "Colorectal Cancer Awareness." https://www.cdc.gov/cancer/dcpc/resources/features/colorectalawareness/index.htm.

National Cancer Institute. "Colorectal Cancer Prevention (PDQ®)–Patient Version." https://www.cancer.gov/types/colorectal/patient/colorectal-prevention-pdq#section/all.

World Health Organization. "Cancer: Carcinogenicity of the Consumption of Red Meat and Processed Meat." https://www.who.int/news-room/questions-and-answers/item/cancer-carcinogenicity-of-the-consumption-of-red-meat-and-processed-meat.