What Are Colorectal Cancer Risk Factors, and Who Is at Risk?

5 min read

What Are Colorectal Cancer Risk Factors, and Who Is at Risk?

Like all types of cancer, there are risk factors that can make you more likely to develop colorectal cancer. Some risk factors, such as diet, obesity, smoking, and alcohol consumption, can be controlled, while others, like your age, personal history, and family history, cannot. 

The good news is that only a small fraction (about 5%) of colorectal cancers are hereditary or caused by inherited genetic mutations. This means it’s even more important that you understand your risk factors so you’ll know when to start screening for colorectal cancer. 

What is Colorectal Cancer?

Colorectal cancer begins when healthy cells in the colon or rectum develop, mutate, or change and grow out of control. Most colorectal cancers begin as small, noncancerous (benign) clumps of cells called polyps that form on the inside of the colon. Over time some of these polyps can become colon cancers. Polyps can also develop and become cancerous in the rectum.

Cancerous polyps usually grow unnoticed, causing no symptoms until they have progressed to a point where treatment is more challenging—a time when it becomes harder to treat. 

Who is At Risk for Colorectal Cancer?

It’s important to remember that anyone can get colorectal cancer. With that said, there are factors that can increase your risk of developing the disease: lifestyle-related risk factors that you can change and non-lifestyle-related risk factors that you can’t. 

Lifestyle seems to play a bigger role than ever before in developing colorectal cancer. This is becoming more evident by the number of people under 40 who have been diagnosed with colorectal cancer in the past few decades. These are things you can control, such as:

  • Being overweight
  • Being physically inactive
  • Eating an unhealthy diet that’s especially high in processed foods (ie, fast food, chips, highly preserved snacks)
  • Smoking
  • Consuming too much red meat 
  • Consuming alcohol
  • Vitamin D deficiency 

If you have more than one risk factor in the list above, it may be a good idea to make some changes. You don’t have to make them all at once, but working towards a lower risk status will help lead a healthier lifestyle. And that’s important for lowering your risk of developing several types of cancer as well as heart disease and type 2 diabetes. 

Risk factors not related to lifestyle choices that are out of your control include: 

  • Age: Colorectal cancer most commonly occurs in people over 50, though it is increasing among those under 50.
  • Race and ethnic background: African Americans have the highest rate of colorectal cancer in the United States. Ashkenazi Jews (Jews of Eastern European descent) are also a high-risk group.
  • Personal or family history: If you or a family member have had colorectal polyps or colorectal cancer, your chance of getting colorectal cancer increases. 
  • Personal history of other diseases: Your risk for developing colorectal cancer increases if you have certain other diseases, including inflammatory bowel disease, ulcerative colitis, or type 2 diabetes. 
  • Inherited genetic syndromes, such as Lynch syndrome (HNPCC) and familial adenomatous polyposis (FAP), are also linked to an increased risk of colorectal cancer. 

Check out our blog: How Ulcerative Colitis Affects Your Risk for Developing Colorectal Cancer

What Steps Can Be Taken to Reduce the Risk of Developing Colorectal Cancer? 

The American Cancer Society guidelines provide recommendations for maintaining a healthy weight, lifestyle, and diet, all of which can reduce cancer risk:

  • Incorporate regular exercise into your routine by setting weekly goals for 2 to 5 hours of moderate-level exercise or 1 to 2 hours of intense physical activity.
  • Make movement a daily habit and take breaks from prolonged sitting and screen time.
  • Add fiber and nutrient-rich fruits, vegetables, and whole grains into your diet.
  • Limit your consumption of processed meats and foods, sugar-sweetened drinks, and refined grains.

Related Reading: Colorectal Cancer and Young Adults: What You Need to Know

Be Proactive By Getting Screened for Colorectal Cancer Regularly

Since the direct cause of colorectal cancer is unknown, understanding your risk factors is important. But so is getting screened.  The goal of screening is early detection of colorectal cancer or even pre-cancerous polyps that can be removed before they turn into cancer.

There really is no other way to find colorectal cancer at an early stage since it doesn’t show symptoms until it’s become more advanced. When symptoms do occur, they often include changes in bowel habits, abdominal cramping or pain, and rectal bleeding. While many of these symptoms could be related to something other than cancer, it’s best to get examined by a doctor rather than ignore them. 

When to Start Colorectal Cancer Screening

The American Cancer Society (ACS) recommends that individuals with an average risk of developing colorectal cancer start regular screenings at age 45. However if you have a family history or your lifestyle produces personal risk factors, you should talk to your doctor by age 30 about a screening schedule that’s right for you. 

Regular screening tests like colonoscopies are an effective way to find colorectal cancer in its early stages when treatment is most successful. Patients of average risk are also able to utilize some at-home testing kits especially before the age of 50. You can also read our blog about when to start screening for colon cancer for more information. 

Related Read: A Simple Test Could Reveal if You’re at High Risk for Developing Colon Cancer

The bottom line is that colorectal cancer screening can save your life, or the life of a loved one. Don’t ignore this uncomfortable topic… talk to your doctor about screening!

Colorectal Cancer Care in Portland-Vancouver

If you or a loved one is diagnosed with colorectal cancer after a screening or at a later stage, Compass Oncology in the Portland and Vancouver area offers the latest in colorectal cancer treatments. Our colorectal cancer doctors work with you to understand your specific diagnosis before recommending a personalized plan.

Request an appointment for a consultation with one of our oncologists at our cancer centers located in the Portland-Vancouver area. We offer second opinions to help you feel comfortable with the treatment plan that’s been recommended.