Research
Colorectal Cancer Screening Now Starts at 45: Why the Age Dropped
Guidelines now recommend colorectal cancer screening begin at age 45, not 50. Here's what changed and why.
Please note: this page is educational only — it is not medical advice, and it does not speculate about anyone’s health beyond reliable public reporting. For questions about your own health, talk with your healthcare team.
What people see in the news
Public awareness campaigns and celebrity stories have spread the message that colorectal cancer screening should now begin at age 45 for people at average risk, not 50 as many long assumed. It's one of the clearer recent shifts in screening guidance.
What it actually means
The American Cancer Society lowered its recommended starting age to 45 in 2018, and in 2021 the U.S. Preventive Services Task Force (USPSTF) — whose recommendations often shape insurance coverage — did the same, recommending screening for average-risk adults ages 45 through 75.
The main reason was a documented rise in colorectal cancer among younger adults. As cases in people under 50 increased, expert groups concluded that starting screening five years earlier would catch more cancers earlier, when they're more treatable, and prevent some cancers entirely.
That prevention point is key. According to the National Cancer Institute, several colorectal screening tests — including colonoscopy, sigmoidoscopy, and stool-based tests — have been shown to reduce the risk of dying from colorectal cancer. Some tests can also find abnormal growths called polyps and allow them to be removed before they ever become cancer. NCI notes expert groups generally recommend regular screening at ages 45 through 75.
What this does and doesn't change
- The change applies to people at average risk. Those with a family history, certain genetic conditions, or inflammatory bowel disease may be advised to start earlier — an individual conversation.
- There's more than one way to screen. NCI describes options including colonoscopy and stool-based tests. The "best" test is partly the one a person will actually do; the choice is worth discussing with a clinician.
- Screening doesn't just find cancer early — it can prevent it by removing polyps. That's a distinctive strength of colorectal screening.
- Symptoms like rectal bleeding or a change in bowel habits should be checked regardless of age, and are not a substitute for screening.
If you're 45 or older, or wondering when to start, our free screening check-up tool can help, and our guide to colorectal cancer screening walks through the options.
Questions to ask a healthcare team
- Should I start colorectal screening now, and which test is right for me?
- Does my family history mean I should start earlier?
- How often will I need to be screened?
- What should I do about symptoms between screenings?
A lower starting age reflects a real rise in colorectal cancer among younger adults — and a chance to catch or prevent more of it. Free, plain-language cancer education helps more people act on guidance like this.