Millennials and Gen Z are confronting a growing health crisis that was once primarily associated with older adults: colorectal cancer is striking younger Americans at unprecedented rates, leaving doctors searching for answers.
Once considered rare in young people, colorectal cancer has become the leading cause of cancer death in men under 50 and the second leading cause in women of the same age group, according to recent data from the National Cancer Institute.
The statistics tell a stark story. According to the American Cancer Society, colorectal cancer diagnoses in people under 55 have doubled from 11% of all cases in 1995 to 20% in 2019. This means one in five colorectal cancer patients is now under 55, compared to just one in ten less than three decades ago.
“I get this question asked a lot when I see younger patients, and I find polyps in them; that’s the most important question they ask me: ‘What can I do to prevent this from happening?'” said Dr. Sameen Khalid, a Lee Health gastroenterologist who has witnessed the trend firsthand.
Medical professionals are especially concerned about how rapidly this shift is occurring. The average age for colorectal cancer diagnosis has dropped from 72 in 2002 to 66 in 2019, reflecting a significant demographic change in who’s affected by this disease.
Perhaps most alarming is the 333% increase in colorectal cancer cases among teenagers aged 15-19 between 1999 and 2020, according to health reports.
This troubling pattern isn’t limited to North America. A comprehensive study published in The Lancet Oncology revealed that early-onset colorectal cancer rates are rising in 27 of 50 countries examined worldwide, with New Zealand, Chile, Puerto Rico and England experiencing the steepest increases.
What makes this trend particularly puzzling is that some young patients present with no obvious risk factors. Many are physically active, maintain healthy diets, and have no family history of the disease.
“We really don’t know one single cause, but it’s likely multifactorial, and risk factors may depend on where the patient lives, what they eat, their lifestyle habits, and other hereditary factors,” explained Dr. Nitin Mishra, an associate professor of surgery at Mayo Clinic in Phoenix.
While researchers continue investigating potential causes, from environmental exposures to dietary changes, the medical community has responded by lowering recommended screening ages. In 2021, the U.S. Preventive Services Task Force revised its guidelines to recommend colorectal cancer screening starting at age 45 instead of 50.
However, doctors worry this may not be enough. Many younger adults continue to be misdiagnosed or have their symptoms dismissed, leading to delayed detection and more advanced disease at diagnosis.
“Primary care doctors don’t think of colorectal cancer in younger patients who are commonly diagnosed instead with inflammatory bowel disease,” noted Dr. Rashmi Verma, an oncologist at UC Davis Comprehensive Cancer Center. “If an at-home test is prescribed and results come back negative, but symptoms continue, tell your doctor you want a colonoscopy.”
Colorectal cancer symptoms include rectal bleeding, changes in bowel habits, persistent abdominal pain, unexplained weight loss, and anemia. Yale Medicine surgeons emphasize that even people in their 20s and 30s should be aware of these warning signs.
“If anyone has any change in their bowel habits, if they have any bleeding—even if they think it’s a hemorrhoid, and it doesn’t go away—just get a colonoscopy,” advised Dr. Vikram Reddy, a Yale Medicine surgeon who conducted one of the first studies identifying this trend about 15 years ago.
The message from medical experts is clear: colorectal cancer is no longer just a concern for older generations. For millennials and Gen Z, awareness and prompt attention to symptoms could make a life-saving difference.