Vitamin D3 — Fat-soluble vitamin / prohormone
Cholecalciferol (D3) is hydroxylated in the liver to 25(OH)D (calcifediol) and then in the kidney (and locally in tissues) to 1,25(OH)2D (calcitriol), the active hormone. Calcitriol binds the vitamin D receptor (VDR), a nuclear receptor expressed in >200 tissue types. Regulates calcium/phosphorus absorption, modulates >1,000 genes, suppresses parathyroid hormone, exerts anti-inflammatory effects through T-regulatory cell induction, and supports innate immunity via cathelicidin upregulation. Observational and interventional data link deficiency to increased risk of fractures, autoimmune disease, cardiovascular events, depression, and all-cause mortality.
نظرة عامة
هذه الصفحة جزء من مكتبة المركّبات المُصنَّفة بالأدلة في Hormonaly. جميع الادعاءات السريرية مرتبطة بمصادر علمية مُحكَّمة عبر خط أنابيب التحقق المزدوج للاستشهادات.
فئة المركّب
Fat-soluble vitamin / prohormone
آلية العمل
Cholecalciferol (D3) is hydroxylated in the liver to 25(OH)D (calcifediol) and then in the kidney (and locally in tissues) to 1,25(OH)2D (calcitriol), the active hormone. Calcitriol binds the vitamin D receptor (VDR), a nuclear receptor expressed in >200 tissue types. Regulates calcium/phosphorus absorption, modulates >1,000 genes, suppresses parathyroid hormone, exerts anti-inflammatory effects through T-regulatory cell induction, and supports innate immunity via cathelicidin upregulation. Observational and interventional data link deficiency to increased risk of fractures, autoimmune disease, cardiovascular events, depression, and all-cause mortality.
الوضع التنظيمي
OTC dietary supplement. Ergocalciferol (D2) and Cholecalciferol (D3) FDA-approved prescription forms exist for deficiency treatment.
مستوى الأدلة
High — multiple large RCTs and meta-analyses (VITAL, D-HEALTH, FIND). Endocrine Society and USPSTF guidelines support supplementation in deficiency.