Colon cancer screening: Who needs a colonoscopy and when?

Let's have a real talk about colon cancer screening, a topic most of us would rather not think about, but it could make a massive difference in your long-term health. If “colonoscopy” sounds scary, gross, or just for “old people,” read on for the straight facts.


Colon cancer (or “colorectal cancer”) is one of the leading causes of deaths in the U.S., but it’s also one of the most preventable. Most colon cancers start as small growths called polyps in your colon or rectum. These can turn into cancer over time. Screening tests, including colonoscopy, can:
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Find polyps before they turn into cancer (and let doctors remove them)

Detect colon cancer early when it’s easiest to treat.

When should you start colon cancer screening?
The clear, science-backed message is: Most adults should start screening at age 45. This isn't just for people with symptoms, screening is for anyone who feels fine but wants to catch issues early. If you’re between 45 and 75 years old, screening is strongly recommended, the CDC says.



Who needs a colonoscopy (versus other tests)?

There are a few ways to screen for colon cancer, but colonoscopy is often called the “gold standard.” When do you need it?


You definitely need a colonoscopy (often sooner than 45) if you:

• Have a personal or family history of colon cancer or certain types of polyps
• Have certain genetic syndromes (like Lynch syndrome or familial adenomatous polyposis)
• Have chronic inflammatory bowel diseases (such as ulcerative colitis or Crohn’s disease)
• Have had colon cancer before, or polyps found in a prior test

For higher-risk folks, doctors may recommend starting before age 45 and repeating colonoscopies more often.

Why colonoscopy?
Colonoscopy is thorough: a doctor uses a flexible camera to look at your entire colon, finds and removes polyps, and can spot cancer early. Yes, it involves some “prep” (you’ll have to clean out your colon the day before), and you’ll likely be sedated. But it’s worth it for peace of mind and prevention.


What if you’re asymptomatic?
Screening is for people without symptoms. If you have symptoms, like blood in your stool, persistent abdominal pain, or unexplained weight loss, talk to your doctor right away. You may need a colonoscopy even if you’re younger than 45.


What to do next

If you’re 45 or older: Ask your doc about scheduling your first screening, even if you feel fine.

If you have a family or personal history or other risk factors: Don’t wait—speak with your doctor about starting sooner.

If you’re over 75: Have a conversation with your doctor about the pros and cons of continued screening.