Why Are More Young Adults Getting Colon Cancer? Risk Factors and Warning Signs Explained

Colorectal cancer is increasingly being diagnosed in younger adults, leaving many patients wondering why cases are rising and whether they may be at risk. Although experts still do not fully understand what is driving the trend, physicians believe several lifestyle, environmental and hereditary factors may be contributing to the increase in diagnoses among younger populations.

In an interview with CURE, Dr. Steven Lee Kong, a colon and rectal surgeon at Hackensack Meridian Health, discussed common colorectal cancer risk factors, symptoms patients should not ignore and the importance of screening and prevention.

“We don’t clearly understand what is driving the shift,” Lee Kong said. “It’s probably not one thing in particular. It’s probably a combination of a bunch of different factors that, taken together as a society, have led to the increasing incidence in young people.”

Symptoms should prompt medical attention

Lee Kong explained that certain symptoms should never be ignored, regardless of a person’s age.

Warning signs may include blood in the stool, bleeding when wiping, changes in bowel habits, new constipation or diarrhea, unexplained abdominal pain and unexplained weight loss.

Importantly, Lee Kong clarified that patients experiencing symptoms are no longer undergoing routine screening, but rather diagnostic evaluation.

“If you have a symptom, then the investigation is a diagnostic investigation,” he said. “Screening is for asymptomatic patients.”

For patients with concerning symptoms, physicians may recommend a colonoscopy or other diagnostic testing to determine the cause.

Colonoscopy plays a role in prevention and detection

Lee Kong said colonoscopy remains one of the most important tools for detecting and preventing colorectal cancer.

In recent years, the recommended screening age for average-risk adults was lowered from 50 to 45 due to the rise in cases among younger adults.

During a colonoscopy, physicians use a thin camera to examine the colon and rectum for cancers or adenomatous polyps, which are small growths that can eventually become cancerous if left untreated.

“If you find these adenomas early enough when they’re small and take them out, you’ve now prevented that adenoma from becoming a cancer down the road,” Lee Kong explained.

He added that colonoscopy is valuable not only for diagnosing colorectal cancer, but also for preventing cancer before it develops.

Family history remains one of the strongest risk factors

Although many younger adults diagnosed with colorectal cancer may not initially believe they are at risk, Lee Kong stressed that family history remains one of the most important known risk factors.

“Having a first-degree relative with a colon or rectal cancer puts someone at increased risk,” he said.

Patients with inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis may also face increased colorectal cancer risk and may require different screening schedules than average-risk patients.

Additionally, patients with a personal history of adenomatous polyps may be more likely to develop future polyps or colorectal cancers.

Because of this, Lee Kong encouraged patients to learn more about their family medical history and discuss any concerns with their physician.

Lifestyle habits may influence risk

In addition to hereditary factors, Lee Kong noted that lifestyle choices may influence colorectal cancer risk.

Research has shown that sedentary lifestyle habits are associated with several health conditions, including colorectal cancer. Regular physical activity may help improve gut motility and reduce systemic inflammation, both of which may play a role in lowering cancer risk.

Diet may also contribute to risk levels.

According to Lee Kong, diets high in red meat and ultra-processed foods, along with low fiber intake, have been associated with increased colorectal cancer risk. Obesity may also play a role.

“In general, understanding their family history, increased physical activity and exercise, and careful attention to diet are all important for reducing one’s risk,” he said.

Alternative screening options are available

Although colonoscopy is considered the standard screening tool, Lee Kong noted that other options exist for patients who are unwilling or unable to undergo the procedure.

“There’s a commercially available stool-based test that you can have that can help detect colorectal cancers,” he said. “It’s actually a very good test for those that are unwilling or unable to get a colonoscopy.”

He encouraged patients to discuss available screening methods with their physician to determine the best option for their individual situation.

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