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Calcium and vitamin D. Diagnostics and therapeutics
1Department of Medicine, Boston University School of Medicine, Massachusetts, USA.
Clinics in Laboratory Medicine
|September 15, 2000
Summary
Vitamin D is essential for bone health. New findings show vitamin D sufficiency may have two levels, impacting both bone and cellular health through extrarenal tissue metabolism.
Area of Science:
- Endocrinology
- Nutritional Science
- Cell Biology
Background:
- Vitamin D is crucial for bone health, obtained through sunlight or diet.
- Adequate vitamin D levels are vital for calcium absorption, bone mineralization, and mobilization.
Purpose of the Study:
- To explore the dual roles of vitamin D metabolism.
- To investigate the implications of extrarenal vitamin D activation for cellular health.
Main Methods:
- Review of existing literature on vitamin D metabolism.
- Analysis of serum 25(OH)D levels and their relation to extrarenal 1,25(OH)2D production.
Main Results:
- 25(OH)D can be converted to 1,25(OH)2D in the colon, prostate, and skin.
- Two potential levels of vitamin D sufficiency are proposed: one for bone health (serum 25(OH)D ≥ 20 ng/mL) and another for cellular health requiring higher levels.
Conclusions:
- Vitamin D sufficiency may be defined by two distinct thresholds.
- Extrarenal metabolism of 25(OH)D to 1,25(OH)2D suggests broader roles for vitamin D beyond bone health.
Keywords:
Non-programmatic
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