Fat and Water Soluble Vitamins
Every day, your body produces skin, muscle, and bone. It churns out rich red blood that carries nutrients and oxygen to remote outposts, and it sends nerve signals skipping along thousands of miles of brain and body pathways. It also formulates chemical messengers that shuttle from one organ to another, issuing the instructions that help sustain your life. To do all this, your body requires raw materials. These include vitamins that your body needs but cannot manufacture on its own in sufficient amounts. A vitamin is“…any of a group of organic substances other than proteins, carbohydrates, fats, minerals, and organic salts which are essential for normal metabolism, growth, and development of the body. Vitamins are not sources of energy, nor do they contribute significantly to the substance of the body. They are indispensable for the maintenance of health. They are effective in minute quantities. They act principally as regulators of metabolic processes…” (Taber, 1993, pg. 2141).
In general, none of the vitamins can be formed in the body but must be obtained from animal or plant sources. Exceptions to the above are the formation of vitamin A from carotene, the formation of vitamin D by the action of ultraviolet light on the skin, and the formation of vitamin K by symbiotic bacteria of the intestine (Merck Research Laboratories, 1992, pg.2139). There are two broad classifications of vitamins. The first, fat-soluble vitamins (A, D, E, and K), must dissolve in fat (or lipids) before they can enter the bloodstream. These vitamins are stored in the liver and fat cells to be released as needed. Because fat-soluble vitamins can be stored, excess amounts can build up over time causing serious toxic reactions. Toxicity rarely occurs from eating foods containing vitamins A, D, E, and K, but rather occurs from taking too many vitamin supplements. The following chart shows the nutrient sources,...
References: Merck Research Laboratories (1992). The Merck Manual (16th ed.). Rathway, NJ: Author.
National Institute of Health. (2012, July). Dietary Supplement Fact Sheet: Vitamin A. Retrieved from http://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/
National Institutes of Health. (2012, July). Dietary Supplement Fact Sheet: Vitamin E. Retrieved from http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
National Institutes of Health. (2012, July). Dietary Supplement Fact Sheet: Vitamin D. Retrieved from http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
National Institutes of Health. (2012, July). Dietary Supplement Fact Sheet: Vitamin K. Retrieved from http://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/
Taber, C. W. (1993). Taber’s Cyclopedic Medical Dictionary (17th ed.). Philadelphia, PA: F.A. Davis Company.
WebMD. (2011, February). Vitamins and Supplements: Vitamins and Their Functions and Sources. Retrieved from http://www.webmd.com/vitamins-and-and-supplements/vitamins-and-their-functions-and-sourc
Please join StudyMode to read the full document