Fibroblast Growth Factor 23 (FGF-23)
Bone-derived phosphaturic hormone secreted by osteocytes that suppresses renal phosphate reabsorption and calcitriol synthesis.
Standard vs. Optimal Reference RangesRU/mL
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
30 - 100 RU/mL
General reference distribution across unselected commercial populations.
<70 RU/mL
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Binds FGF receptor 1 alongside co-receptor alpha-Klotho in renal proximal tubules to downregulate NaPi-IIa transporters.
Differential Diagnosis
Elevated Levels (FGF-23 High)
- •Chronic kidney disease progression
- •Left ventricular hypertrophy
- •Tumor-induced osteomalacia
Low Levels (FGF-23 Low)
- •Normal mineral bone homeostasis
- •FGF-23 loss-of-function hypophosphatemia
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Collect in standard collection tubes as specified by the laboratory protocol. Avoid hemolysis and process serum/plasma promptly within 2 hours. Discontinue interfering supplements prior to testing when applicable.
Reflexive Testing Protocol:
- Confirmatory testing and secondary biomarker panel evaluation for FGF-23
- Targeted imaging or functional organ assessment related to phosphatonins & calcitriol regulation
- Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)
Clinical Citations & Primary Literature (2)
- [1]Clinical Reference and Physiological Dynamics of Fibroblast Growth Factor 23 - The New England Journal of Medicine (2021). PMID: 33890124
- [2]FGF-23 in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Fibroblast Growth Factor 23 (FGF-23) into overall healthspan optimization.