From the Guidelines
The recommended age to begin regular colonoscopy screening for average-risk individuals is 45 years old. This is based on the most recent guidelines from the American Cancer Society, 2018, and the National Comprehensive Cancer Network, 2022, as well as the US Multi-Society Task Force on Colorectal Cancer, 2022, which all recommend starting screening at age 45 with any test 1. Screenings should then continue periodically until age 75, typically every 10 years if results are normal.
Key Considerations
- For people with a family history of colorectal cancer, personal history of inflammatory bowel disease, or certain genetic syndromes, screening may need to start earlier, sometimes as young as age 40 or 10 years before the youngest case in the family, as recommended by the National Comprehensive Cancer Network, 2022, and the US Multi-Society Task Force on Colorectal Cancer, 2022 1.
- The preparation for colonoscopy typically involves a clear liquid diet the day before the procedure and drinking a bowel-cleansing solution to empty the colon completely.
- This screening is crucial because colorectal cancer often develops slowly from precancerous polyps, which can be removed during the procedure before they become cancerous.
Special Considerations
- After age 75, the decision to continue screening should be individualized based on prior screening history, overall health, and life expectancy, as the benefits may be outweighed by the risks of the procedure for very elderly patients, as suggested by the US Preventive Services Task Force, 2021 1.
- The American College of Gastroenterology, 2021, also recommends colonoscopy every 10 years or FIT every 1 year as primary screening modalities for average-risk adults between ages 50 and 75 years 1.
From the Research
Age for Colonoscopy
- The recommended age for colonoscopy screening varies depending on the individual's risk factors and family history of colorectal cancer 2, 3.
- For average-risk individuals, the US Multi-Society Task Force on Colorectal Cancer recommends starting colonoscopy screening at age 45 3.
- However, some studies suggest that the prevalence of colorectal neoplasia in individuals aged 40-49 is lower than in those aged 50-59, which may not support lowering the age threshold for colonoscopy in the general population 4, 5.
- Despite this, colonoscopy before age 50 is increasingly common, with about 5% of individuals in one health plan cohort having a record of colonoscopy before age 50 6.
- First-degree relatives of colorectal cancer patients are recommended to start screening at age 40 or 10 years before the age at diagnosis of the youngest relative diagnosed with colorectal cancer 2.
- The decision to start or continue screening for individuals ages 76 to 85 should be individualized and based on prior screening history, life expectancy, colorectal cancer risk, and personal preference 3.
- Screening is not recommended after age 85 3.