Vitamin D Flashcards
what are its three hydroxyl groups? Vitamin D
Calcitriol, Calciferol, (Cholecalciferol)
what is it? Vitamin D
hormone
what is its precursor? Vitamin D
cholesterol
what are the two things its blocked by? Vitamin D
melanin and sunscreen
what the RDI? Vitamin D
15 min/day (light), 38 min (dark)
what theory is associated with it? Vitamin D
theory of racial differences
where was it discovered? Vitamin D
dogs who were inside and dogs who were outside
what are the three things associated with its function in calcium metabolism? Vitamin D
Increases absorption of Ca from intestine, Increases resorpIon of Ca from bone, Increases Ca & P resorpIon by kidney
what are its two functions? Vitamin D
calcium metabolism, Influences gene acIvity
what is the trabecular? Vitamin D
the spongy bone where constant remodeling occurs by osteoclast and osteoblast
what is osteoblast? Vitamin D
the process of new bone being added in the trabecular
what is osteoclast? Vitamin D
the process of the degradation of bone surface in the trabecular
what are the four consequences of deficiency? Vitamin D
Ca not absorbed from intesIne or resorbed by kidney, Bones dissolve to maintain blood Ca levels, Rickets, Osteomalacia
what is the deficiency disease in children? Vitamin D
rickets
what three things make a child suseptable to rickets? Vitamin D
Crowded smoky industrial areas, dark-skinned people, In purdah
what are the seven things that can happen when a child gets rickets? Vitamin D
Inadequate deposition of Ca, bones remain soft, Bowing of legs, Rachitic rosary, Failure of fontanel to close, Late eruption of teeth; less well formed, Retarded growth
what are the two deficiency diseases in adults? Vitamin D
Osteomalacia, Osteoporosis
what are the three things that happen as a result of getting osteomalacia? Vitamin D
Softening of bones, Brittle, malformed
what are the eight things that can cause osteomalacia? Vitamin D
Inadequate intake or absorption of vitamin D
• Inadequate intake or absorption of Ca
• Excess resorption of Ca (repeated pregnancies)
• Breast feeding without supplementation
• Gastric surgery, alcoholics
• Kidney removal, liver cirrhosis
what does Cadmium Toxicity do? Vitamin D
Cadmium replaces Ca in bone
what the disease associated with Cadmium Toxicity? Vitamin D
Itai-itai disease
what happens with Itai-itai disease? Vitamin D
tendons cant connect bone because its soft
where’s a typical place people get Cadmium Toxicity? Vitamin D
Polluted areas of China
what are the four things that happen with the deficiency disease Osteoporosis? Vitamin D
Lack of bone matrix & Ca, Fragile bones fracture, Compaction of bone, lose height
when does the Dowager’s hump occur? Vitamin D
when people get osteoporosis and there bones compact and they lose height
at what age does our peak bone mass occur? Vitamin D
30 yrs
is osteoporosis inevitable with age? if so at what age? Vitamin D
Inevitable with age, especially > 80 yr
why are the elderly more prone to get osteoporosis? Vitamin D
Elderly drink lifle milk, not outside as much • Lose ability to synthesize acIve form
whats happens with toxicity? Vitamin D
Increases blood Ca –> Ca deposition in soft Issues
when blood Ca increases due to toxicity what three things occur? Vitamin D
Kidney Stones
• CalcificaIon of arteries • Mental confusion
when are the three times toxicity can occur? Vitamin D
Occurs at 25X RDI; 2X in pregnancy; Cod liver oil, halibut liver oil
what are the four main food sources? Vitamin D
cod liver oil, certain fish, milk, some cereals
whats the RDI for adults? Vitamin D
15 μg/day
whats the RDI for people > 70 yrs? Vitamin D
20 μg/day
