HUMNNTR 2210 Lecture Notes - Lecture 17: Phylloquinone, Dark Skin, Osteomalacia
24 Oct 2016
School
Department
Course
Professor
Document Summary
Vitamin d: maintain blood calcium/phosphorus, bone-mobilize calcium. Intestine-increase calcium and phosphorus absorption: kidney-reabsorb calcium and phosphorus, maintain bone integrity. Vitamin d: forms: active form: calciferol, cholesterol in skin [irradiated (uv rays)] made into vitamin d. Vitamin d: deficiency: children weak bones lead to rickets, cure with cod-liver oil (1700s, adults osteomalacia bone softening. Calcium is present but not utilized: minimal sunlight exposure, kidney (cid:272)a(cid:374)"t convert to active form, ca(cid:374)"t absorb from intestinal tract, occurs in: In children: deficiency prevents rickets, but larger amounts results in more rapid growth and earlier eruption of teeth. In older children: larger amounts favor calcium retention. Vitamin d: sources: eggs, milk, vitamin d fortified, fish oils. Vitamin d: toxicity: 3000-4000 iu/day results in elevated serum calcium levels, over 20,000 iu/day serious toxicity, symptoms: Kidney damage loss of weight: bones, blood increase calcium withdrawal increased ca and p level, nervous loss of appetite irritability. Alpha tocopherol: widely available in normal diet.
