Risk Factors

Everyone is at risk for developing colorectal cancer, but not everyone’s risk is the same.

Risk Factors

Everyone is at risk for developing colorectal cancer, but not everyone’s risk is the same.

Polyps and cancer can develop when there are issues with how the cells in the colon’s lining normally grow and replace themselves. This
is a process called cell division. In the lining of the colon, cells are constantly aging, dying, and being replaced by new cells. Every time cells divide, there is a risk of something going wrong and abnormal cells developing.

Certain factors can raise your chances of cell division going awry, but they don’t always cause it. Just because you have risk factors of colon cancer, it doesn’t necessarily mean you’ll get cancer.

Knowing your risk factors can help you decide when to get screened and how to protect your health.

What’s your risk? Take our Colorectal Cancer Screening Quiz to find out.

Polyps and cancer can develop when there are issues with how the cells in the colon’s lining normally grow and replace themselves. This
is a process called cell division. In the lining of the colon, cells are constantly aging, dying, and being replaced by new cells. Every time cells divide, there is a risk of something going wrong and abnormal cells developing.

Certain factors can raise your chances of cell division going awry, but they don’t always cause it. Just because you have risk factors of colon cancer, it doesn’t necessarily mean you’ll get cancer.

Knowing your risk factors can help you decide when to get screened and how to protect your health.

What’s your risk? Take our Colorectal Cancer Screening Quiz to find out.

Am I at risk for colon cancer?

Below are the known risk factors of colorectal cancer.

Age is one of the top risk factors for colorectal cancer. As our bodies get older, the likelihood that errors will occur in the process of cell division goes up. Colorectal cancer is more common in older adults, even though it is becoming more common in younger people.

The median age of diagnosis is 66.

Simply put: The older you get, the higher your risk of colorectal cancer.

Most experts and guidelines recommend regular screening start at age 45.

Colorectal cancer can run in families. If a first-degree relative has had colorectal cancer or colon polyps, your colorectal cancer risk is higher. First-degree blood relatives include parents, siblings, and children.

As many as 1 in 3 colorectal cancer patients report that a blood relative has also had the disease. The causes might involve genes inherited from parents that increase the risk of cancer, along with environmental factors.

If the family member with colorectal cancer was under age 50 at the time of diagnosis, or if multiple family members have been diagnosed with colorectal cancer, the risk for blood relatives is even higher than if only one relative or only an older relative has had the disease.

Tell your family members if the doctor found polyps.

Family history doesn’t only apply to relatives with cancer. If a first-degree relative had a polyp found and removed, that can also increase your risk of having polyps.

Not all types of polyps increase your cancer risk, and it is important to understand exactly what kind of polyp was removed.

Discuss your family history with your doctor, and discuss your screening results with your family members. Openly sharing health information can save lives.

If a colonoscopy found large or advanced polyps, you are at an increased risk for developing colorectal cancer. If polyps are not removed, they can turn into cancer. Sometimes an additional procedure is needed to remove polyps if they cannot be removed during a colonoscopy.

Once you’ve discovered that you have a polyp, your risk to develop future polyps is elevated. Stay on schedule with the screening plan your doctor recommends.

Advanced polyps are often referred to as premalignant or precancerous, and these have a high risk of turning into cancer if not removed.

A colonoscopy is the only colorectal cancer screening option that can identify polyps remove them in the same procedure. Other screening tests, like Cologuard (stool test) or CT colonography (x-ray) can identify polyps, but a colonoscopy will be needed to remove them.

If you’ve been diagnosed with inflammatory bowel disease (IBD)—like Crohn’s disease or ulcerative colitis—you are at an increased risk for colorectal cancer. IBD tends to damage and cause inflammation in the inner lining of the colon and rectum, and inflammation can create an environment for abnormal cells to grow.

You’re likely seeing a gastroenterologist if you’ve been diagnosed with IBD, so discuss your increased risk of colorectal cancer and an appropriate screening plan.

If you’ve been previously diagnosed with breast cancer, ovarian cancer, uterine cancer, or pancreatic cancer, your risk of having colorectal cancer is increased. If you’ve previously been diagnosed with colorectal cancer, this also escalates your risk of facing a recurrence or developing additional colorectal cancers. If you’ve had prior radiation therapy on your abdomen or pelvis to treat a prior cancer, this also increases your risk.

It’s important to stick to your follow-up plan (also called surveillance) set by your doctor to monitor and prevent future cancer cases.

Your risk of developing another cancer is higher if you were younger when you were diagnosed with the first cancer.

People with type 2 diabetes are at an increased risk for colorectal cancer. Factors that make you more likely to get type 2 diabetes, like being overweight and not being active, can also raise your chances of getting colorectal cancer. Having type 2 diabetes might affect how well you do if you have colorectal cancer.

Your lifestyle, diet, and physical activity all play into colorectal cancer risk. Studies have shown that being overweight or obese is a risk factor, especially in men. Lack of physical activity also increases your colorectal cancer risk. Regular exercise has been proven to lower risk.

What you eat, drink, and smoke can put you at a higher risk for colorectal cancer:

  • Little fruit, vegetable, grains, and fiber in your diet
  • Low vitamin D
  • Smoking tobacco
  • Heavy alcohol use (more than one drink a day for women and two drinks a day for men)
  • A diet high in red meat (beef, pork, lamb), processed meats (hot dogs, sausage, lunch meats), and fats
  • A diet that includes a lot of sugary drinks
  • Meat preparation methods that includes frying, grilling, broiling, or other methods of cooking that use very high temperatures that can lead to charring of the surface of the food

The following racial groups in the United States are getting diagnosed and passing away at higher rates compared to other ethnicities:

  • Alaska Natives
  • American Indians
  • African Americans
  • Young Hispanics
  • Worldwide, Jews of Eastern European descent (Ashkenazi Jews) may have the highest risk of colorectal cancer.

While both men and women can get colorectal cancer, it’s more commonly diagnosed in men, and men more often die from the disease.

Doctors might recommend getting tested sooner if your race and background raise your chances of having colorectal cancer. Read more about race and ethnicity risks:

  • CDC: Colorectal Cancer by Age, Sex, Race and Ethnicity
  • SEER: Cancer Stat Facts: Colorectal Cancer
  • ACS: Colorectal Cancer Statistics 2023

If you have been diagnosed with a hereditary colorectal cancer syndrome, you are at high risk for colorectal cancer. About 5% of colorectal cancer patients have a hereditary cancer syndrome.

People with these syndromes and their family members should have regular and early screenings for colorectal and other cancers. These steps can detect precancerous growths or cancers in their early stages, when they are most likely to be curable.

The most common genetic syndromes include:

  • Lynch syndrome (or HNPCC) (2%-4% of all colorectal cancers)
  • Familial adenomatous polyposis (FAP) (1% of all colorectal cancers)

Although rarer, the following genetic syndromes also put you at a high risk:

  • Peutz-Jeghers syndrome (PJS)
  • MUTYH-associated polyposis (MAP)
  • Cystic fibrosis (CF)

Am I at risk for colon cancer?

Below are the known risk factors of colorectal cancer.

Age is one of the top risk factors for colorectal cancer. As our bodies get older, the likelihood that errors will occur in the process of cell division goes up. Colorectal cancer is more common in older adults, even though it is becoming more common in younger people.

The median age of diagnosis is 66.

Simply put: The older you get, the higher your risk of colorectal cancer.

Most experts and guidelines recommend regular screening start at age 45.

Colorectal cancer can run in families. If a first-degree relative has had colorectal cancer or colon polyps, your colorectal cancer risk is higher. First-degree blood relatives include parents, siblings, and children.

As many as 1 in 3 colorectal cancer patients report that a blood relative has also had the disease. The causes might involve genes inherited from parents that increase the risk of cancer, along with environmental factors.

If the family member with colorectal cancer was under age 50 at the time of diagnosis, or if multiple family members have been diagnosed with colorectal cancer, the risk for blood relatives is even higher than if only one relative or only an older relative has had the disease.

Tell your family members if the doctor found polyps.

Family history doesn’t only apply to relatives with cancer. If a first-degree relative had a polyp found and removed, that can also increase your risk of having polyps.

Not all types of polyps increase your cancer risk, and it is important to understand exactly what kind of polyp was removed.

Discuss your family history with your doctor, and discuss your screening results with your family members. Openly sharing health information can save lives.

If a colonoscopy found large or advanced polyps, you are at an increased risk for developing colorectal cancer. If polyps are not removed, they can turn into cancer. Sometimes an additional procedure is needed to remove polyps if they cannot be removed during a colonoscopy.

Once you’ve discovered that you have a polyp, your risk to develop future polyps is elevated. Stay on schedule with the screening plan your doctor recommends.

Advanced polyps are often referred to as premalignant or precancerous, and these have a high risk of turning into cancer if not removed.

A colonoscopy is the only colorectal cancer screening option that can identify polyps remove them in the same procedure. Other screening tests, like Cologuard (stool test) or CT colonography (x-ray) can identify polyps, but a colonoscopy will be needed to remove them.

If you’ve been diagnosed with inflammatory bowel disease (IBD)—like Crohn’s disease or ulcerative colitis—you are at an increased risk for colorectal cancer. IBD tends to damage and cause inflammation in the inner lining of the colon and rectum, and inflammation can create an environment for abnormal cells to grow.

You’re likely seeing a gastroenterologist if you’ve been diagnosed with IBD, so discuss your increased risk of colorectal cancer and an appropriate screening plan.

If you’ve been previously diagnosed with breast cancer, ovarian cancer, uterine cancer, or pancreatic cancer, your risk of having colorectal cancer is increased. If you’ve previously been diagnosed with colorectal cancer, this also escalates your risk of facing a recurrence or developing additional colorectal cancers. If you’ve had prior radiation therapy on your abdomen or pelvis to treat a prior cancer, this also increases your risk.

It’s important to stick to your follow-up plan (also called surveillance) set by your doctor to monitor and prevent future cancer cases.

Your risk of developing another cancer is higher if you were younger when you were diagnosed with the first cancer.

People with type 2 diabetes are at an increased risk for colorectal cancer. Factors that make you more likely to get type 2 diabetes, like being overweight and not being active, can also raise your chances of getting colorectal cancer. Having type 2 diabetes might affect how well you do if you have colorectal cancer.

Your lifestyle, diet, and physical activity all play into colorectal cancer risk. Studies have shown that being overweight or obese is a risk factor, especially in men. Lack of physical activity also increases your colorectal cancer risk. Regular exercise has been proven to lower risk.

What you eat, drink, and smoke can put you at a higher risk for colorectal cancer:

  • Little fruit, vegetable, grains, and fiber in your diet
  • Low vitamin D
  • Smoking tobacco
  • Heavy alcohol use (more than one drink a day for women and two drinks a day for men)
  • A diet high in red meat (beef, pork, lamb), processed meats (hot dogs, sausage, lunch meats), and fats
  • A diet that includes a lot of sugary drinks
  • Meat preparation methods that includes frying, grilling, broiling, or other methods of cooking that use very high temperatures that can lead to charring of the surface of the food

The following racial groups in the United States are getting diagnosed and passing away at higher rates compared to other ethnicities:

  • Alaska Natives
  • American Indians
  • African Americans
  • Young Hispanics
  • Worldwide, Jews of Eastern European descent (Ashkenazi Jews) may have the highest risk of colorectal cancer.

While both men and women can get colorectal cancer, it’s more commonly diagnosed in men, and men more often die from the disease.

Doctors might recommend getting tested sooner if your race and background raise your chances of having colorectal cancer. Read more about race and ethnicity risks:

  • CDC: Colorectal Cancer by Age, Sex, Race and Ethnicity
  • SEER: Cancer Stat Facts: Colorectal Cancer
  • ACS: Colorectal Cancer Statistics 2023

If you have been diagnosed with a hereditary colorectal cancer syndrome, you are at high risk for colorectal cancer. About 5% of colorectal cancer patients have a hereditary cancer syndrome.

People with these syndromes and their family members should have regular and early screenings for colorectal and other cancers. These steps can detect precancerous growths or cancers in their early stages, when they are most likely to be curable.

The most common genetic syndromes include:

  • Lynch syndrome (or HNPCC) (2%-4% of all colorectal cancers)
  • Familial adenomatous polyposis (FAP) (1% of all colorectal cancers)

Although rarer, the following genetic syndromes also put you at a high risk:

  • Peutz-Jeghers syndrome (PJS)
  • MUTYH-associated polyposis (MAP)
  • Cystic fibrosis (CF)

Is everyone at risk?

Everyone who has a colon is at risk for colorectal cancer, but everyone’s risk level is different.

What are the risk levels?

Your risk for colorectal cancer is similar to that of the general U.S. population. Approximately 1 in 20 people with average risk will develop colorectal cancer in their lifetimes. However, screening and healthy lifestyle choices can reduce this risk. Guidelines recommend that people of average risk begin screening at age 45.

Talk to your provider about their preferred screening schedule and screening methods for your situation.

If you have a first-degree relative with a history of colorectal cancer, you should be begin screening 10 years before the age of the diagnosis of your youngest relative with colorectal cancer, or at age 40, whichever comes first. Talk to your provider about when you should begin screening if you have a personal history of inflammatory bowel disease of the colon, or a personal or family history of large or advanced polyps in your colon or rectum.

Speak to your physician about hereditary cancer risk and consider meeting with a genetic counselor.

What can I do to lower my risk?

Some risk factors like race, ethnicity, and personal or family history of cancer or polyps cannot be changed. This is why it’s important to know your risk and create a screening plan with your doctor.

However, some risk factors can be improved.

Stop smoking. Eat a diet full of fruits, vegetables, and fiber.

One recommended diet is the “Mediterranean diet,” and many cookbooks and websites can help you find recipes and meal plans.

Exercise that lowers risk can take many forms, and aerobic exercise should be a part of any plan. Aerobic exercise can include walking, running, hiking, biking, swimming, and many other activities. Research suggests that 120 minutes or more of aerobic exercise per week reduces health risks.

Avoid a diet full of processed meats and red meats. Don’t drink alcohol—or if you choose to drink, limit your intake to one or two drinks per day or less. Check your vitamin D levels to ensure you’re not deficient and take supplements if your levels are low.

These are steps that won’t only make you healthier overall, but they’ll lessen your colorectal cancer risk, too.

Is everyone at risk?

Everyone who has a colon is at risk for colorectal cancer, but everyone’s risk level is different.

What are the risk levels?

Your risk for colorectal cancer is similar to that of the general U.S. population. Approximately 1 in 20 people with average risk will develop colorectal cancer in their lifetimes. However, screening and healthy lifestyle choices can reduce this risk. Guidelines recommend that people of average risk begin screening at age 45.

Talk to your provider about their preferred screening schedule and screening methods for your situation.

If you have a first-degree relative with a history of colorectal cancer, you should be begin screening 10 years before the age of the diagnosis of your youngest relative with colorectal cancer, or at age 40, whichever comes first. Talk to your provider about when you should begin screening if you have a personal history of inflammatory bowel disease of the colon, or a personal or family history of large or advanced polyps in your colon or rectum.

Speak to your physician about hereditary cancer risk and consider meeting with a genetic counselor.

What can I do to lower my risk?

Some risk factors like race, ethnicity, and personal or family history of cancer or polyps cannot be changed. This is why it’s important to know your risk and create a screening plan with your doctor.

However, some risk factors can be improved.

Stop smoking. Eat a diet full of fruits, vegetables, and fiber.

One recommended diet is the “Mediterranean diet,” and many cookbooks and websites can help you find recipes and meal plans.

Exercise that lowers risk can take many forms, and aerobic exercise should be a part of any plan. Aerobic exercise can include walking, running, hiking, biking, swimming, and many other activities. Research suggests that 120 minutes or more of aerobic exercise per week reduces health risks.

Avoid a diet full of processed meats and red meats. Don’t drink alcohol—or if you choose to drink, limit your intake to one or two drinks per day or less. Check your vitamin D levels to ensure you’re not deficient and take supplements if your levels are low.

These are steps that won’t only make you healthier overall, but they’ll lessen your colorectal cancer risk, too.

Medical Review

Richard Goldberg, MD

West Virginia University Cancer Institute

Date reviewed: 12/18/23