Colonoscopy Screening Age Recommendations
For average-risk individuals, you can request colonoscopy screening starting at age 45, though the strongest evidence supports beginning at age 50. 1, 2
Starting Age by Risk Category
Average-Risk Individuals (No Family History)
- Age 50 is the standard recommendation with the strongest evidence for non-African American individuals to begin colorectal cancer screening 3, 1, 4
- Age 45 is now recommended by major societies including the American Cancer Society and USPSTF, though this carries a qualified/conditional recommendation based on rising cancer rates in younger adults 1, 2, 4
- The USPSTF provides a Grade A (strongest) recommendation for screening ages 50-75, but only a Grade B recommendation for ages 45-49 1, 2
African Americans
- Begin screening at age 45 due to higher incidence rates and increased risk of advanced polyps 3, 1, 2
- This recommendation addresses important health disparities, though it is based on weaker evidence 1
High-Risk Individuals
- Age 40 or 10 years younger than the youngest affected relative (whichever comes first) if you have a first-degree relative diagnosed with colorectal cancer or advanced adenoma before age 60 3, 1, 4
- Age 25 for hereditary nonpolyposis colorectal cancer (HNPCC) 1
- Age 10-12 for familial adenomatous polyposis (FAP) 1
- 8-10 years after symptom onset for inflammatory bowel disease (ulcerative colitis or Crohn's disease) 1
Stopping Age for Screening
- Age 75 if you are up to date with screening and have had negative prior tests, particularly a negative colonoscopy 1, 2, 4
- Consider screening up to age 85 if you have never been screened, depending on overall health and life expectancy 1, 2, 4
- Do not screen beyond age 85 as harms outweigh benefits at this age 1, 2
- Stop at any age when life expectancy falls below 10 years regardless of prior screening history 1, 2, 4
Evidence Quality and Clinical Context
The recommendation to begin at age 45 rather than 50 reflects recent trends showing rising colorectal cancer incidence in younger adults 3, 1. However, research demonstrates that while adenoma prevalence is similar between ages 40-49 and 50-59 (11-14% vs 16-23%), the rate of advanced adenomas is significantly higher in the 50-59 age group 5, 6, 7. The number needed to screen to detect one advanced lesion is 49 in the 40-49 age group compared to only 20 in those aged 50-59 6.
Common Pitfalls to Avoid
- Failing to screen African Americans at age 45 rather than waiting until age 50 1, 2
- Not obtaining thorough family history including age of diagnosis in relatives, which determines whether screening should begin at age 40 3, 1
- Continuing screening beyond age 85 when evidence consistently shows harms exceed benefits 1, 2
- Not verifying family history information, which is often incomplete or inaccurate 1