Medically Reviewed by Dr. K on 7 May 2021
Table of contents
Risk Factors For Colorectal Cancer
Colorectal cancer may affect anyone. The exact underlying causes are unclear however there are a few clear risk factors associated with this disease. Below are 9 risk factors of colorectal cancer.
Colorectal cancer is more prevalent in people over 50, and the risk of developing it increases with each decade after 40. Cancer is very uncommon in individuals under the age of 40, with the exception of those with a significant family history of the disease.
Men are more likely than women to have colorectal cancer. Colon cancer affects both men and women similarly, but men are more likely to have rectal cancer.
These growths on the colon’s or rectum’s inner wall are not cancerous, but they can contribute to it. People above the age of 50 are most likely to get them. A form of polyp known as an adenoma increases the risk of colorectal cancer. Adenomas are a precursor of colon and rectal cancer.
Your health history
If you’ve had colorectal cancer previously, it’s possible that you’ll get it again, particularly if you had it before the age of 60. If you’ve had polyps, this also has a high likelihood of recurrence, which in turn increases your risk of developing colorectal cancer. Colorectal cancer is often more common in individuals who have long-term illnesses involving bowel inflammation, such as Ulcerative Colitis or Crohn’s Disease.
It’s possible that the rare genes in colon cells that trigger polyps and cancers run in your family. You’re more likely to get colorectal cancer if you have a parent, sibling, or child that has had it. If the relative was diagnosed before the age of 45, or if you have a significant family history of colorectal polyps or cancer, the risk increases. If you have a family history of disorders like genetic adenomatous polyposis, MYH-associated polyposis, or inherited non-polyposis colorectal cancer, you’re more likely to develop colon cancer (and other cancers).
Colorectal cancer may be more common in people who consume a lot of red meat, fat, and cholesterol but little fiber or fresh vegetables.
If you consume a lot of alcohol, smoke, don’t get enough exercise, have a sedentary lifestyle or are overweight, you have a higher risk of colorectal cancer.
Colorectal cancer is more common in people with diabetes.
Colorectal cancer is more common in African Americans than in other racial and ethnic groups.
Red Flag Warning Symptoms and Signs
You’re much more likely to develop polyps or cancer if you have a mixture of these risk factors. Talk to the doctor about your concerns and update them if anything changes. They will be able to advise you about how to reduce the risk and when you can get tested.
The following are a list of red flag warning signs and symptoms of colorectal cancer you should not ignore:
- A persistent new change in your bowel patterns, such as diarrhoea or constipation, or a change in the consistency of your stool.
- Rectal bleeding
- Blood in your stool
- Persistent abdominal discomfort, like cramps, gas, bloating or abdominal pain.
- A sensation that your bowel doesn’t empty completely when you go to the toilet.
- Weakness or fatigue
- Unexplained weight loss
In the early phases of colon cancer, several patients show no signs or symptoms. Symptoms may likely vary depending on the size and location of the cancer in the large intestine.
Referenced on 14/4/2021
- The American Cancer Society medical and editorial content team. (2020). Colorectal cancer risk factors.
- The American Cancer Society medical and editorial content team. (2020). Key statistics for colorectal cancer.
- The American Cancer Society medical and editorial content team. (2020). Survival rates for colorectal cancer.
- The American Cancer Society medical and editorial content team. (2020). Targeted therapy for colorectal cancer.
- The American Cancer Society medical and editorial content team. (2020). What is colorectal cancer?
- Beg M, et al. (2015). 8 common myths about colon cancer.
- Buskermollen M, et al. (2019). Colorectal cancer screening with faecal immunochemical testing, sigmoidoscopy or colonoscopy: A microsimulation modelling study. DOI:
- Mayo Clinic Staff. (2019). Colon cancer.
- National Cancer Institute: “Colorectal Cancer Screening (PDQ)," “What You Need to Know About Cancer of the Colon and Rectum."
- American Cancer Society: “Colorectal Cancer Overview."