← Blood tests
CTX (C-Telopeptide)
Specialistalso beta-crosslaps, ctx-1
What it isCTX is a fragment of type 1 collagen released into blood when osteoclasts (bone-resorbing cells) break down bone matrix.
DoesReports the rate of bone resorption.
GoodMid-range CTX with adequate bone formation markers signals balanced remodeling.
BadHigh CTX signals accelerated bone loss in osteoporosis. Low CTX confirms response to bisphosphonate therapy but if suppressed too low may track atypical fracture risk.
- Standard
- Men 87–1200 pg/mL; women premenopausal 25–573, post 104–1008 pg/mL.
- Optimal
- 250–500 pg/mL men, 150–400 pg/mL premenopausal women (lower is good within range)
- Modifiers
- Diurnal — highest overnight, fast for accurate AM measurement; rises after fracture.
How to optimize
- Lifestyle
- Weight-bearing and resistance training; avoid prolonged inactivity.
- Diet
- Adequate protein and calcium.
- Supplements
- Vitamin D3, vitamin K2 MK-7, calcium from food, magnesium glycinate.
- Peptides
- —
- Drugs
- Bisphosphonates, denosumab, raloxifene suppress resorption.
MagnesiumVitamin D3Vitamin K2Calcium
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 Bone Density