Vitamin D, 1,25-OH (Calcitriol)
Specialistalso active vitamin d
What it isCalcitriol is the active hormonal form of vitamin D, produced by the kidneys from 25-OH vitamin D. It binds the vitamin D receptor and drives gene expression.
DoesRegulates calcium absorption from the gut, modulates immune, and influences hundreds of genes.
GoodA mid-range calcitriol with appropriate 25-OH vitamin D signals balanced vitamin D physiology.
BadCalcitriol can be normal or high even when 25-OH vitamin D is low — making it a poor screening test. It rises pathologically in granulomatous disease (sarcoidosis, tuberculosis) and some lymphomas.
- Standard
- 19.9–79.3 pg/mL.
- Optimal
- 35–65 pg/mL (narrow target)
- Modifiers
- Tightly regulated; rises with PTH, falls with kidney disease.
How to optimize
- Lifestyle
- —
- Diet
- —
- Supplements
- Don't supplement active calcitriol without a specific indication.
- Peptides
- —
- Drugs
- Calcitriol and analogues used in chronic kidney disease and specific conditions.
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.
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