Certain conditions, lifestyle habits, and other factors may increase your risk of colorectal cancer. Managing your risk factors can help lower your chances of developing this cancer and get the support you need for early diagnosis and treatment.

Colorectal cancer includes rectal cancer that starts in your rectum and colon cancer that starts in your colon. It may spread from your rectum or colon to other parts of your body.

Your risk of colorectal cancer may be higherTrusted Source if you have a family history of the disease, certain health conditions, or certain lifestyle habits. Your doctor will recommend colorectal cancer screening and may encourage you to make lifestyle changes to help manage the risk.

We spoke with Rachel Issaka, MD, MAS, to learn more about colorectal cancer risk factors and how to manage them. Dr. Issaka is a gastroenterologist and the director of the Population Health Colorectal Cancer Screening Program at the Fred Hutch Cancer Center in Seattle, WA.

Read on to learn what she had to say and find answers to common questions about colorectal cancer risk.

Colorectal cancer develops when DNA changes in cells in your colon or rectum cause them to grow out of control.

Sometimes, DNA changes that cause colorectal cancer are inherited (passed from parent to child).

Inherited genetic syndromes that increase your chances of colorectal cancer includeTrusted Source:

  • hereditary nonpolyposis colon cancer (HNPCC) or Lynch syndrome
  • familial adenomatous polyposis (FAP)
  • attenuated FAP (AFAP)
  • Gardner syndrome
  • Peutz-Jeghers syndrome
  • MUTYH-associated polyposis (MAP)
  • Cystic fibrosis

“It’s important to know your family history of colon cancer and other cancers that are associated with colon cancer. That’s related to understanding what genes are prevalent in your family,” explained Dr. Issaka.

A combination of other factors may also trigger DNA changes that cause colorectal cancer, such as:

  • certain environmental factors
  • certain lifestyle habits
  • aging processes

Researchers are continuing to study the exact causes of colorectal cancer, including how different factors may interact to trigger DNA changes.

Major risk factors for colorectal cancer includeTrusted Source:

  • family history of colorectal cancer
  • age over 50 years
  • overweight or obesity
  • low physical activity
  • diet high in fat or processed meat
  • diet low in fiber, fruits, or vegetables
  • alcohol consumption
  • tobacco use

Your risk of colorectal cancer is also higher if you have certain health conditions, such as:

  • certain inherited genetic syndromes listed in the section above
  • inflammatory bowel disease (IBD), like Crohn’s disease or ulcerative colitis
  • primary sclerosing cholangitis (PSC)

According to the American Cancer SocietyTrusted Source, American Indian and Alaska Native people have the highest rates of colorectal cancer in the United States, followed by African American men and women. The condition can affect people of any sex, gender, and race.

Although adults over 50 years old are more likely than younger adults to develop colorectal cancer, diagnoses and deaths from this disease have been increasing in younger adults.

“That’s led most of the medical societies that make colorectal cancer screening recommendations to reduce the screening age to 45 years to try to catch cancer early before it has progressed,” said Dr. Issaka.

Guidelines from the American College of Gastroenterology, American Cancer SocietyTrusted Source, and U.S. Preventive Services Task Force (USPSTF) all support screening for colorectal cancer starting at age 45 years if you have an average risk of this cancer.

Your doctor may recommend starting screening at a younger age if you have certain risk factors, such as IBD, PSC, or a strong family history of this cancer.

Certain lifestyle habits or factors may increase your risk of colorectal cancer, as well as some other types of cancer.

“We know there are certain things that increase your risk of many cancers, including colorectal cancer — and those things include exposure to alcohol, tobacco, foods that are high in fats, and meats that are processed,” said Dr. Issaka. “Obesity is another risk factor that cuts across multiple cancers,” she added.

Talk with your doctor about your lifestyle and ask whether there are certain changes you could make to help reduce your risk of colorectal cancer.

Following recommendations for colorectal cancer screening and practicing healthy lifestyle habits can lower your chances of developing colorectal cancer.

Colorectal cancer screening

Colorectal cancer screening involves medical tests to check for precancerous polyps that may turn into cancer, as well as colorectal cancer that’s already developed but isn’t causing symptoms.

Your doctor may order a colonoscopy to screen for colorectal cancer. During this procedure, a doctor uses a flexible tube with an attached light and camera to look inside your colon and rectum.

They may order another testTrusted Source before colonoscopy, such as a:

  • fecal immunochemical test or other stool-based test
  • flexible sigmoidosocopy
  • CT scan or other imaging test

If this test is positive for potential signs of cancer, they will order a follow-up colonoscopy to look for and remove precancerous polyps and take tissue samples to check for cancer cells.

Polyps are tissue growths that can turn into cancer over time. Removing precancerous polyps before they become cancer can help prevent colorectal cancer.

Lifestyle changes

“There are some easy lifestyle changes that everyone can incorporate into their day-to-day practice to lower their overall cancer risk,” said Dr. Issaka.

Examples include:

  • taking steps to manage your weight
  • getting regular physical activity
  • eating a fiber-rich diet with a wide variety of fruits, vegetables, whole grains, and lean proteins
  • limiting your consumption of high fat foods and processed meats
  • avoiding tobacco products and secondhand smoke
  • limiting or avoiding alcohol

“I encourage all of my patients to try and implement as many of these healthy lifestyle habits as much as possible,” said Dr. Issaka. “Although I want to note that for some people who will be diagnosed with colorectal cancer, they will do all of these things and still get colorectal cancer.”

Let your doctor know if you’re finding it difficult to practice healthy habits or make changes to your lifestyle. They may share strategies or resources or refer you to a specialist, such as a registered dietitian or smoking cessation counselor.

Colorectal cancer is curable, especially with early diagnosis and treatmentTrusted Source. Colorectal cancer is more challenging to treat and cure after it’s spread to other parts of your body.

Speak with your doctor to learn about your treatment options and outlook if you have colorectal cancer.

Dr. Issaka recommends speaking with your doctor sooner rather than later to learn about colorectal cancer screening and strategies to manage your risk.

Consider asking:

  • What are my risk factors for colorectal cancer?
  • Can I make lifestyle changes or take other steps to manage my risk factors?
  • Can you share tips or resources to help me make those changes?
  • When should I start getting colorectal cancer screening?
  • What type of screening tests do you recommend?
  • How often should I get the screening tests?
  • What happens if a test result is abnormal or positive for signs of cancer?

“It’s never too early to start talking about screening, especially for those [with a] family history,” said Dr. Issaka.

If you don’t have a primary care doctor or healthcare team that you see regularly, you may be able to get a stool test kit from a pharmacist or public health agency to start the colorectal cancer screening process. You can use the kit to collect a sample of your stool and send it to a medical laboratory for testing. The lab will check for potential signs of colorectal cancer.

“Before you complete that stool test, regardless of where you receive it from, make sure that you have a plan for how you’re going to handle an abnormal result,” said Dr. Issaka.

“So, if somebody in the community gives you a test, ask them: ‘What is going to happen if I have an abnormal result?’ And if they don’t have a clear answer for you, I would discourage you from doing the test at that time.”

Dr. Issaka said it’s important to connect with a healthcare system that can help you understand an abnormal stool test result and guide you through the next steps. An abnormal stool test result must then involve a colonoscopy to learn whether precancerous polyps or colorectal cancer cells are present.

“If it’s abnormal and you don’t get that follow-up colonoscopy, then the benefit of preventing cancer won’t be realized,” she added.

Your chances of developing colorectal cancer depend on whether you have certain risk factors. Your doctor can help you understand your risk factors and how to manage them.

They can also help you understand your treatment options and outlook if you develop colorectal cancer.

The outlook for colorectal cancer improves when people receive early diagnosis and treatment.

Your risk of colorectal cancer is higher if you have a family history of the disease or you have certain genetic syndromes, such as Lynch syndrome, or certain inflammatory conditions, like IBD or PSC.

Your risk of colorectal cancer is also affected by certain lifestyle factors, such as diet, activity level, and tobacco or alcohol use.

Although colorectal cancer is more common in adults over the age of 50 years, it can also affect younger adults. That’s why experts recommend starting screening for colorectal cancer at age 45 years if you have average risk or younger if you have certain risk factors.

Screening for colorectal cancer can help your doctor find and remove precancerous polyps before they turn into cancer or diagnose colorectal cancer early. Talk with your doctor to learn when to start screening, how often you should get screening and what the tests involve.

A doctor can also help you learn about lifestyle changes that may lower your risk of colorectal cancer.