NTR 306 Chapter Notes - Chapter 11: Vitamin A Deficiency, Vitamin D Deficiency, Hypervitaminosis D
Document Summary
Storage: vitamin a = mainly liver, vitamins a, k & e = mainly liver, vitamin d mainly = fat and muscle tissue. A family of fat-soluble retinoids: retinol, retinal, and retinoic acid are the 3 active forms in the body, preformed vitamin a = retinyl esters. Found primarily in animal foods: provitamin a compounds (the most active is beta-carotene) converted to retinal. Carotenoids pigments which give color to some fruits & veggies like carrots, butternut squash and cantaloupe. Absorption can be increased by inclusion of fat in a meal. Functions: vision, growth and development of cells and healthy bones, reproduction, a healthy immune system. Too much: excessive amounts of preformed vitamin a accumulate to toxic levels. Hypervitaminosis a serious liver damage and result in death: overconsumption. During pregnancy birth defects in the face, skull and cns of the child. Can potentially result in osteoporosis and bone fractures in adults: carotenoids in foods are not toxic.
