الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 99 |  |  |
| | | from | 99 | | |
Abstract
The water-soluble vitamins include ascorbic acid (vitamin C), thiamin, riboflavin, niacin, vitamin B6 (pyridoxine, pyridoxal, and pyridoxamine), folacin, vitamin B12, biotin, and pantothenic acid. Vitamins play a vital role in many biochemical functions in the human body and are essential components for maintaining optimal health. There are two main groups of vitamins – fat-soluble and water-soluble (washed out and not easily stored). Although adequate intake of all vitamins is important, regular intake is required to avoid deficiency due to the transient nature of water-soluble vitamins. Vitamin B complex and vitamin C are found in many foods, especially vegetables and fruits, as well as dairy, meat, legumes, peas, liver, eggs, and fortified grains and cereals. In addition to serving as cofactors in biochemical reactions, the vitamin B complex is vital for normal body growth and development, healthy skin, the proper function of nerves and the heart, and red blood cell formation. Biotin (B7) is necessary for the metabolism of protein, fats, and carbohydrates. Deficiency can lead to muscle pain, heart problems, anemia, and depression. Additionally, since biotin is a contributor to keratin, biotin has become popularized as a supplement to improve the quality of hair, skin, and nails. When egg whites are cooked, the avidin denatures and does not bind biotin as avidly.Of note, TSH levels are unaffected by biotin supplementation.Cobalamin (B12) is essential for erythropoiesis and the growth of the nervous system. Deficiency may lead to pernicious anemia and subacute combined degeneration of the spinal cord. The macrocytic megaloblastic anemia from B12 deficiency presents similarly to folate deficiency, and to differentiate them, it is imperative to obtain serum homocysteine and methylmalonic acid levels. In folate deficiency, homocysteine will elevate, but methylmalonic acid levels will be normal. In vitamin B12 deficiency, both homocysteine and methylmalonic acid levels will present as elevated. Additionally, B12 deficiency will present with neurologic symptoms, whereas folate deficiency will not.