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Vitamins a and C

Essay by   •  November 30, 2011  •  Essay  •  1,245 Words (5 Pages)  •  1,309 Views

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As written in the textbook, vitamins " are organic nutrients of various forms that the body requires in small amounts". On the other hand what do you really know about vitamins and why do we need them. Two of the many vitamins needed to live a healthy life are vitamins A and C. They are simply known to be good for you, but why?

Elmer V. McCollum and M. Davis discovered Vitamin A, also called Vitamin A Retinol. There is no exact date of discovery, however, it was during the years of 1912-1914 that it was found. In 1913, Thomas Osborne and Lafayette Mendel found that butter had a "fat-soluble nutrient" now known as Vitamin A. The suggested daily dose for Vitamin A varies on age and gender (after the age 14). From ages 1-3 the Recommended Dietary Allowance (RDA) is 300 micrograms (mcg) per day. Ages 4-8 the RDA is 400mcg per day. Ages 9-13 the RDA is 600mcg per day. For males, ages 14 and older the RDA is 900mcg per day. For females, ages 14 and older the RDA is 700mcg per day. The body uses vitamin A for "vision, bone growth, reproduction, cell division, and cell differentiation". Vitamin A also advances the surface linings of the "eyes and the respiratory, urinary, and intestinal tracts", to prevent bacteria from entering the body. There are two types of sources of vitamin A, animal or plant. Vitamin A that comes from animal sources is called performed vitamin A, which is absorbed in the form of retinol. Retinol is an active form of vitamin A. Vitamin A that come from plant sources are called provitamin A carotenoid, or just carotenoid. There are different forms of carotenoids such as beta-carotene, alpha-carotene, and beta-cryptoxanthin. Beta-carotene is mostly made into retinol. The best sources of vitamin A in animal sources are liver, cheese, fortified milk, and eggs. The best sources of vitamin A in plants are vegetables such as "carrots, pumpkins, and sweet potatoes". Other sources of just the beta-carotene in plants are "broccoli, spinach, and most dark green vegetables". Basically any of the "bright yellow and orange fruits" are also sources of vitamin A. Any of these foods are best recommended with low saturated fats and trans fats. Too much of vitamin A is called Hypervitaminosis A which is a "high storage level of vitamin A in the body. This may lead to many toxic symptoms and defects. Four major symptoms and defects are " birth defects, liver abnormalities, reduced bone mineral density, and central nervous system disorders". However, too many carotenoids will have no major health concerns except the skin may turn yellow, which isn't considered dangerous to your health. Too little vitamin A may cause vitamin A deficiency. Vitamin A deficiency is when not enough vitamin A is in the body. Some effects include night blindness and become more likely to infectious diseases. As mentioned before there are many different diseases that can occur if there is too much of vitamin A or too little, however recent studies show that vitamin A can lower risk of many types of cancer. Also, when taking too much vitamin A can weaken the bones causing Osteoporosis. The body does store vitamin A in the liver where it can be spread throughout the body when needed. When taking vitamin A age and gender only take in effect when a certain amount of vitamin A is needed, as I mentioned before in the RDA for age and gender.

Axel Holst and Alfred Fröhlich discovered Vitamin C, also known as ascorbic acid, in 1907. In 1931-1945 Albert Szent-Györgyi helped prove that the acid is identical to the antiscurvy vitamin C. The RDV of vitamin C is determined by age and gender (only after the age of 14). The RDV for ages 1-3 are 15 milligrams (mg) per day. For ages 4-8 the RDV is 25mg per day. From ages 9-13 the RDV is 45mg per day. The RDV for males, ages 14-18 is 75mg per day, for females it is 65mg per day. The RDV for males, ages 19 and older

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