For a long time, colorectal cancer — cancer of the colon or rectum — was considered a disease mostly affecting older adults. But in recent years, doctors have noticed something alarming: more and more people under 50 are being diagnosed. This rise is worrying because younger patients often don’t expect it, and symptoms can easily be overlooked.

So, what’s happening? And what can you do to protect yourself?
Cases Are Rising Among Young Adults
While overall colorectal cancer rates in older adults have gone down thanks to better screening and awareness, cases among people in their 20s, 30s, and 40s are going up. Experts aren’t entirely sure why, but several lifestyle and biological factors seem to be involved:
- Diet: High consumption of processed foods and red meat, and low intake of fiber, fruits, and vegetables.
- Sedentary lifestyles: Long hours sitting at work or home without enough physical activity.
- Obesity and metabolic health issues: Being overweight or having insulin resistance can increase risk.
- Gut health changes: Shifts in the gut microbiome — the balance of bacteria in the intestines — may play a role.
Researchers are still studying how these factors interact, but what’s clear is that younger adults are no longer immune.
Genetics Can Be Important
Even though most young-onset colorectal cancers aren’t inherited, genetics still matter. People diagnosed under 50 are more likely than older adults to have inherited syndromes such as:
- Lynch syndrome
- Familial adenomatous polyposis (FAP)
Doctors recommend that young patients get genetic testing after a colorectal cancer diagnosis. This can guide treatment and also alert family members who might be at higher risk, allowing them to start screening early.
Family History Matters More Than You Think
Knowing your family’s medical history is crucial. If you have a parent, sibling, or close relative who had colorectal cancer, your risk is higher.
In such cases, doctors may recommend starting screening earlier than the standard age of 45. Sometimes it’s advised to begin 10 years before the age at which your relative was diagnosed. Screening can catch precancerous growths early, which is often life-saving.
Younger Patients Can Handle Treatment — But It’s Not a Guarantee
One upside of being younger is that people often tolerate aggressive treatments like surgery, chemotherapy, or radiation better than older adults. This can improve outcomes.
However, being young doesn’t automatically mean the cancer will be less aggressive. In fact, patients under 35 may face faster-growing, more aggressive tumors, making early detection even more critical.
Watch Out for Warning Signs
Colorectal cancer can be tricky in young adults because symptoms are often subtle or mistaken for less serious issues. Don’t ignore:
- Blood in the stool (bright red or dark)
- Persistent changes in bowel habits (constipation, diarrhea, or thinner stools)
- Ongoing abdominal pain or cramps
- Unexplained fatigue or weight loss
- Feeling like your bowel never empties completely
Doctors encourage patients to speak openly about these symptoms. Even if you’re young, it’s better to check and be safe than ignore them.
Key Takeaways
Colorectal cancer in young adults is rising, but awareness, early detection, and healthy lifestyle choices can make a real difference. Here’s what you should do:
- Know your family history and share it with your doctor.
- Pay attention to changes in your body, especially bowel habits or blood in the stool.
- Maintain a healthy diet rich in fiber, fruits, and vegetables.
- Stay active, exercise regularly, and manage your weight.
- Talk to your doctor about screening, even if you’re under 45.
Being proactive is key. Early detection saves lives, and lifestyle changes can lower your risk. Don’t wait for symptoms to worsen — take control of your gut health today.
Why Colorectal Cancer Is Increasing Among Young Adults: What You Need to Know
