Vitamins PDF

Vitamins Introduction Vitamins may be defined as organic compounds occurring in small quantities in different natural foods and necessary for growth and maintenance of good health in human beings and in experimental animals. Introduction Vitamins are essential food factors, which ar...

Vitamins Introduction Vitamins may be defined as organic compounds occurring in small quantities in different natural foods and necessary for growth and maintenance of good health in human beings and in experimental animals. Introduction Vitamins are essential food factors, which are required for the proper utilization of the proximate principles of food like carbohydrates, lipids and proteins. Discovery of vitamins Started from observation of deficiency manifestations, e.g. scurvy, rickets, beriberi, etc. Discovery of vitamins Begun in the year 1911 by a Polish American biochemist Casimir Funk. Father of vitamins and vitamin therapy. Coined the word vitamin Discovery of vitamins Sir Frederick Gowland Hopkins (Nobel Prize, 1929) Growth stimulating vitamins. Amino acid tryptophan, isolated it from protein showed that it and certain other amino acids cannot be manufactured by certain animals from other nutrients and must be supplied in the diet. Two classifications of vitamins 1.Fat soluble vitamins 2.Water soluble vitamins Two classifications of vitamins 1.Fat soluble vitamins A, D, E, K Soluble in fats but not in water. Absorbed along with lipids, requires bile salts Carrier proteins are present. Stored in liver. Not excreted Deficiency manifests only when stores are depleted. Toxicity- Hypervitaminos is may result Treatment - Single large doses may prevent deficiency. Two classifications of vitamins Two classifications of vitamins 2. Water soluble vitamins B and C Not soluble in fats but soluble in water. Simple absorption No carrier proteins No storage Excreted in the body Deficiency m,anifests rapidly as there is no storage Toxicity - Unlikely, since excess is excreted Treatment - regular dietary supply is required Vitamin A Fat soluble. Active form is present only in animal tissues. The pro-vitamin, beta-carotene is present in plant tissues. Group of interrelated substances (retinol, retinal and retinoic acid). Retinal is found in the cells of the eye where it plays a vital part in the perception of light Vitamin A deficiency is a major public health problem in the developing world. Vitamin A Found in potato, carrots, pumpkins, spinach, beef and eggs. Vitamin D Facilitate the uptake of calcium from food, through the lining of the small intestine into the blood. It also controls the deposition of calcium in the bones during growth and maintains adult bone structure. Vitamin D deficiency cause failure in skeleton development.  Vitamin D In the skin, ultraviolet light (290- 315 nm) breaks the bond between the steroid ring. So, the ring B is opened, to form the provitamin, secosterol. The cis double bond is isomerized to a trans double bond to give rise to vitamin D3 or cholecalciferol. Vitamin D Found in fortified milk and other dairy products.  Vitamin E Most powerful natural antioxidant Not a single compound, but consists of a group of eight closely related chemicals, of which the most important. Responsible for about 90% of its activity in the body is alpha-tocopherol. Inactivates free radical attacks and keeps the structural and functional integrity of all cells. Vegetable oils are rich sources of vitamin E; e.g. wheat germ oil, sunflower oil, safflower oil, cotton seed oil, etc Vitamin E Found in fortified cereals, leafy green vegetables, seeds, and nuts. Vitamin E Vitamin K The main role of vitamin K is in blood clotting. Increase bone density in osteoporosis. Deficiency could therefore result in an increasing tendency to bleed. In children and adults, Vitamin K deficiency may be manifested as bruising tendency, ecchymotic patches, mucous membrane hemorrhage, post- traumatic bleeding and internal bleeding. Vitamin K Found in dark green leafy vegetables and in turnip or beet green. Vitamin B Vitamin B complex Consists of a whole range of different compounds, some of which have similar functions and work together. Sufficiently different from one another to be given individual names or numbers, and to be listed separately on many food labels. Vitamin B12, the body can only store limited amounts of B vitamins and because they are all water-soluble, any excess is excreted in the urine. Vitamin B Vitamin B1 or Thiamin: Found in pork chops, ham, enriched grains and seeds. Vitamin B2 or Riboflavin: Found in whole grains, enriched grains and dairy products. Vitamin B3 or Niacin: Found in mushrooms, fish, poultry, and whole grains. Vitamin B5 or Pantothenic Acid: Found in chicken, broccoli, legumes and whole grains. Vitamin B6 or Pyridoxine: Found in fortified cereals and soy products. Vitamin B7 or Biotin: Found in many fruits like fruits and meats. Vitamin B9 or Folic Acid: Found in leafy vegetables. Vitamin B12: Found in fish, poultry, meat and dairy products. Vitamin C Water soluble and is easily destroyed by heat, alkali and storage. Vitamin C takes part in many of the body's metabolic processes and acts as an antioxidant (destroying free radicals). Found in citrus fruits and juices, such as oranges and grapefruits. Vitamin C Seatwork (1/2 cw) Classification of Specific Source General/Main Vitamins Vitamins Function 1. 3. 9. 15. 4. 10. 16. 5. 11. 17. 6. 12. 18. 2. 7 13. 19. 8. 14. 20. thank you!