Flashcards in Vit D controversy Deck (20):
What is the right level of Vitamin D?
What is the relationship of UVR and Vit D?
cannot protect skin from damaging effects of UVR without decreasing formation of vit D
What is the active form of vitamin D?
When taking blood, what compound is Vitamin D measured?
25-hydroxy-vitamin D3 [25(OH)D3]
Who is at greatest risk for vitamin D deficiency?
elderly; northern latitudes, dark skin, elderly, obese
What are sources of Vit D?
What is the primary cause of epidemic low vitamin D worldwide?
decreased skin synthesis of vitamin D
What are causes of reduced skin synthesis of vitamin D?
season, latitude, skin pigment; aging; sunscreen; photprotection;
What are disease associated causes of vit D deficiency?
decreased bioavailability (malabsorption, obesity); heritable and acquired disorders; decreased synthesis (liver, renal)
What are key genes and pathways associated with vitamin D?
proliferation, differentiation, apoptosis, angiogenesis
What are the functions of vitamin D?
acts with PTH to maintain normal levels of calcium and phosphate
Systemically, what are the results of vitamin D?
increases intestinal absorption of Ca, PO4, Mg;
osteolytic effect on bone;
decreased renal clearance
What is the pathogenesis of Rickets?
Vitamin D deficiency leading to softening and weakening of bones associated with bending bones, Fxs
What is the Tx for rickets?
What are adult skeletal manifestations of Vit D deficiency?
osteomalacia, osteopenia, osteoporosis, muscle weakness
What are the benefits of vitamin D supplementation?
daily oral supplementation of 800 IU; frail and elderly; enhances strength and decreases from fracture
What are the risk factors for individuals with 25 hydroxyvitamin D levels below 20ng/mL?
30-50% increase risk in colon cancer, prostate, breast cancer;
higher mortality from these cancers
What are the diseases more common at high latitudes?
CV disease; schizophrenia; depression; wheezing illnesses; autoimmune disease
If a person does not get adequate sun exposure, how can vit D be supplemented?
diet (supplements) => Vit D3 better and more effective at maintaining serum 25-hydroxyvitamin D levels