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Unformatted text preview: e form = 1,25 dihydroxycholecalciferol Function Sources Regulate Ca and P absorption during bone growth RDA Diet: D2 (milk additive, plant sources) and D3 (animal sources) Precursor: intermediate in cholesterol synthesis Formed in skin nonenzymatically from steroid 7dehydrocholesterol 5 g D3 Soft bones, impaired growth and skeletal deformities in children (Rickets) Also caused by antiepileptic drugs Most toxic (stored, slowly metabolized) Deficiency Toxicity Vitamin K Phylloquinone or menaquinone Function O CH3 CH3 O CH3 CH3 Sources Synthesis of bloodclotting proteins K1 = plants; K2 = animals, bacteria in intestine Cabbage, cauliflower, spinach, egg yolk, liver 90120 g/day Unlikely due to synthesis and wide distribution in food Injection for infants Jaundice Vitamin K1 (phylloquinone) RDA Deficiency O CH3 CH3 O CH3 CH3 Toxicity Vitamin K2 (menaquinone) Vitamin E Tocopherol Function Sources Antioxidant, prevent oxidation of polyunsaturated FAs in membranes by O2 and free radicals Vegetable oils, liver, eggs, nuts, seeds, spinach, tomatoes 15 mg
HO CH3 H3C CH3 O RDA CH3 CH3 CH3 CH3 CH3 Deficiency Toxicity Associated with defective lipid transport/absorption Hemolytic anemia Least toxic of fatsoluble vitamins Olestra Artificial, noncaloric fat substitute (indigestible) FDA warning "This Product Contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E, and K have been added." O R C O CH2 H H O R C H O C R O O O R H O O C R O H O C O R O O H O CH2 H O C R O O O CH2 R C H R = (CH2)7CH=CH(CH2)7CH3...
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