← Blood tests
CEA (Carcinoembryonic Antigen)
Specialistalso —
What it isA protein produced during fetal development that some cancers — particularly colorectal — re-express in adulthood.
DoesMonitors treated colorectal cancer for recurrence; not a screening test.
GoodLow CEA in someone with treated colorectal cancer signals disease control.
BadRising CEA in treated colorectal cancer flags recurrence; also rises in smokers, IBD, and benign liver conditions.
- Standard
- <5 ng/mL (nonsmokers).
- Optimal
- 0–2.5 ng/mL nonsmoker (lower is good)
- Modifiers
- Rises with smoking, inflammatory bowel disease, benign liver conditions.
How to optimize
- Lifestyle
- Quit smoking.
- Diet
- —
- Supplements
- —
- Peptides
- —
- Drugs
- Cancer-directed therapy when indicated.
Reference ranges are general adult lab norms; optimal ranges are editorial picks from the longevity literature — not medical advice. Always interpret results with your physician.
within Cancer Markers