young woman with a colon cancer diagnosis
credit: Liza Summer

The Connection Between Young Adults and Colon Cancer

Here’s a look at why younger adults are being diagnosed with colon cancer and how they can lower their risk

Jill MacDonald, now an ambassador for Fight Colorectal Cancer, was 37 years old when she was diagnosed with stage 4 colorectal cancer (also known as colon cancer) in 2015. “I have been dealing with this for over nine years now,” MacDonald said. “I have been through an unimaginable number of chemotherapy treatments, radiation, surgeries, procedures — the list goes on.”

Initially, MacDonald’s symptoms were dismissed. “I had some night sweats pretty consistently — a little blood in my stool,” she explained. “My abdomen felt a little uncomfortable at times. I had some back pain. My doctor told me it was likely just hemorrhoids (swollen veins in the anus and lower rectum).”

Unfortunately, MacDonald’s doctor was wrong, and she is one of an increasing number of people receiving a colon cancer diagnosis at a younger age than typical.

Colon cancer, the third most common cancer in the U.S., is more commonly diagnosed in older adults. However, the disease is rising in people under the age of 50 and is now the third deadliest type of cancer in women ages 20–49. And, according to stats from a March 2023 report by the American Cancer Society, approximately 19,550 people under age 50 will be diagnosed with colon cancer. This represents a 9% increase since 2020.

Colorectal cancer that is diagnosed in someone under age 50 is called early-onset colorectal cancer. As more and more younger adults are being diagnosed, physicians and researchers have noticed that they are more likely to develop an aggressive form of the disease and are 40% more likely to be diagnosed at a more advanced stage.

The five-year survival rate for colon cancer is 90%, decreasing to 71% for stage 3 and 14% for stage 4. The five-year survival rate is the percentage of people in a study or treatment who were alive five years after being diagnosed with or starting treatment for cancer.

Delayed diagnosis of colon cancer

Many younger people don’t think of colon cancer as something they could have, which can lead to delays in diagnosis.

“The issue is that they’re diagnosed later than we would otherwise expect in the older population because most young folks don’t think they have cancer,” Nehal J. Lakhani, M.D., Ph.D., the director of Clinical Research at the START Center for Cancer Research Midwest, said. “They’re more likely to not seek medical attention. They may attribute running stool to hemorrhoids or something else.”

In addition, doctors aren’t offering screening for younger adults for early-onset colorectal cancer. The U.S. Preventive Services Task Force typically recommends that adults ages 45 to 75 receive a colorectal screening. Yet, millennials, who are people born between 1981 and 1996, have twice the risk of colorectal cancer compared to those born in 1950.

“We as physicians failed to recognize symptoms in the younger population because we don’t expect them to have cancer due to our general understanding of the disease,” Lakhani said.

Why are more younger adults being diagnosed with colon cancer?

Researchers aren’t sure what’s behind the increase in younger adults being diagnosed with colon cancer. Genetics can play a role in getting colon cancer at a young age, particularly if you have Lynch syndrome. However, that doesn’t explain the increase. Lifestyle factors, like a lack of exercise or alcohol and tobacco use, and environmental exposure to toxins and chemicals are being considered as possible influences.

Some other theories include:

Red or processed meats: The NCI reports that red or processed meats are associated with an increased risk of colorectal cancer. Some examples of specific foods include beef, pork and lamb.

“The World Health Organization (WHO) classified processed meats as a Group 1 carcinogen — the same degree of certainty as cigarette smoking,” Lakhani explained. “Red meat has also been classified as a carcinogen, but in a lower category as a Group 2 carcinogenic.”

Socioeconomic status: A person’s socioeconomic status involves their education, income and job type. People with a lower socioeconomic status may have less access to health resources and poorer health than those with a higher socioeconomic status. That said, younger adults with a lower socioeconomic status may be more likely to get colon cancer.

“If you’re from a lower socioeconomic status, you may not have health insurance,” Lakhani said. “Or you have access to healthcare, but it’s not the best quality of care.”

Signs and symptoms of colon cancer in younger adults

The signs and symptoms of colorectal cancer (cancer in the colon and rectum) can include the following:

  • Blood in stool
  • Dark or black stools
  • Unintentional weight loss

The NCI reports four additional potential warning signs of colorectal cancer in young adults, including:

  • Stomach pain
  • Rectal bleeding
  • Diarrhea
  • Iron deficiency anemia

How to prevent or lower the risk of colon cancer

Here are a few actions you can take to lower your risk of developing colorectal cancer:

Eat a healthy diet

  • Avoid red or processed meats
  • Add a good amount of fruits and vegetables to your diet
  • Eat a high amount of fiber, between 21–28 grams daily for women, depending on your age

Stay physically active

Advocate for yourself

Because screening is typically recommended for older adults, and healthcare providers (HCPs) may dismiss your symptoms, it is important to advocate for your health.

Read: My Doctor Dismissed My Colon Cancer Red Flags as Normal Pregnancy Symptoms >>

“Being a young patient, you may have to be your own advocate for things to happen in the healthcare system,” Lakhani said. “[If] you’re continuing to have symptoms and you’re not getting them investigated, you might have to push for [medical care].”

If you suspect you have colon cancer, see your HCP quickly and don’t take no for an answer if you want to get screened. Get a second opinion if you feel your HCP isn’t listening to you.

If you do receive a colon cancer diagnosis, Lakhani suggested finding a good oncologist quickly and addressing the problem as early as possible so you can get the best possible results.

This educational resource was created with support from Merck.


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