الرئيسية
VITAMIN D
Vitamin D is a fat-soluble vitamin
Vitamin D3 is produced in the skin of vertebrates after exposure to ultraviolet B light from the sun
and occurs naturally in a small range of foods such as fatty fish, eggs, and meat are rich in vitamin D and are often recommended for consumption to those suffering vitamin D deficiency
Vitamin D is carried in the bloodstream to the liver where it converts to calcidiol then convertes into calcitriol (وهو ده الشكل الفعال لفيتامين د)
هنا هنقف شوية ..
علشان يتحول ال
calcidiol
إلى
calcitriol
ده بيحصل بطريقتين : داخل الكلية أو عن طريق كرات الدم البيضاء
1-When synthesized by monocyte-macrophagesكرات الدم البيضاء, calcitriol acts locally as a cytokine, defending the body against microbial invaders.
2-When synthesized in the kidneys, calcitriol circulates as a hormone regulating the concentration of calcium and phosphate in the bloodstream, promoting the healthy mineralization, growth and remodeling of bone, and the prevention of hypocalcemic tetany
**sufficiency prevents rickets in children and osteomalacia in adults, and, together with calcium, helps to protect older adults from osteoporosis. Vitamin D also modulates neuromuscular function, reduces inflammation, and influences the action of many genes that regulate the proliferation, differentiation and apoptosis of cells.
**Deficiency results in impaired bone mineralization, and leads to bone softening diseases including:
-Rickets
-Osteomalacia
