<p>Vitamin B-Complex and Vitamin C function as cofactors of various enzymes which regulate carbohydrate, protein and fat metabolism. Thiamine (B.,) acts as a cofactor in the decarboxylation of keto acids such as pyruvic acid.<br />
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Riboflavin (B2) plays a vital role in cellular respiratory reactions in conjunction with nicotinamide.<br />
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Pyridoxine (B6) takes part in decarboxylation and interconversion of amino acids. It is also required for normal antibody-mediated and cell-mediated immune responses.<br />
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Vitamin B12 (cyanocobalamin) is required for synthesis of DNA (deoxyribo-nucleic acid) and maturation of RBCs (red blood cells). Nicotinamide (niacinamide) plays a vital role in cellular respiration in conjunction with riboflavin.<br />
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Calcium Pantothenate functions as a cofactor for enzymes involved in transfer of acetyl groups. It is also required for normal antibody response in conjunction with pyridoxine.<br />
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Folic acid, after conversion in the body to folinic acid, takes part in reactions involved in the synthesis of nucleotides and maturation of RBCs in conjunction with vitamin B12. It also plays an important role in lymphocyte-mediated immune response.<br />
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Ascorbic acid (Vitamin C) takes part in biochemical reactions involving oxidation, as in collagen synthesis, and in conversion of folic acid to folinic acid. It is also necessary for normal phagocytic function ofWBCs (white blood cells).<br />
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Thus an adequate supply of these water-soluble vitamins is required for the optimum function of various cells and tissues.Except for Vitamin B12, these water-soluble vitamins are not stored in the body to any significant extent, the excess quantities being excreted in the urine. Therefore, a regular and adequate intake of them is necessary to meet the metabolic requirements. Deficiencies of water-soluble vitamins often co-exist because of their overlapping dietary sources and metabolic interdependence. Initially the deficiency of these vitamins may be subclinical and demonstrable only by means of biochemical tests. If not corrected at this stage, it may become manifest as various symptoms, including impaired wound healing and increased susceptibility to infection.&nbsp;Classical deficiency diseases such as beri beri, pellagra and scurvy are rare, whereas mild and subclinical deficiencies are probably more common, even among apparently healthy individuals.</p>