Vitamin-C or ascorbic acid is a white crystalline, odorless compound readily soluble in water and is most easily susceptible to destruction by atmospheric oxidation. It is a strong reducing agent and is comparatively stable in an acid medium, but is destroyed by the action of heat and catalysts such as copper. Loss of the vitamin often results from storage, processing and cooking.
1. This vitamin is important for the formation and maintenance of collagen, a protein that is widely distributed in the body. Collagen is the cementing material that holds the cells of the body together and is also necessary for the healing of wounds and fractures.
2. It is also essential for the formation of teeth and bones and for production and repair of tissues.
3. Ascorbic acid also plays an important role in the normal metabolism of amino acids as tyrosine and in the function of the adrenal gland.
4. Ii helps in easy absorption of iron from the gastro-intestinal tract by the reduction of ferric iron to ferrous iron.
Fruits and vegetables are the main sources of ascorbic acid. Citrus fruits like limes, lemons, oranges, mosambis, grapes and tomatoes. Vitamin-C is also found in considerable amount in fresh mangoes, Papayas and other fruits. Cauliflower, green leafy vegetables, raw cabbages, green chilies also supply Vitamin-C. Guavas and sprouted grams are valuable sources of Vitamin-C. Dry legumes contain small amount of Vitamin- C, which increases in manifold, approximately 7 times during germination. However animal foods do not contain much of Vitamin-C.
Since Ascorbic acid cannot be stored in the body, the requirement has to be met daily from the diet. The recommended daily allowance is 20 mg. to 40 mg. for children and 40 mg for an adult. An extra allowance is also recommended for nursing mother.
Deficiency of Vitamin-C makes the gums soft, tender that bleeds easily. If there are cuts and wounds, it takes a long time to heal. Jaws become swollen and tender. The body becomes susceptible to infection and disease. Premature signs of old age appear in the young. In case of acute deficiency, a disease, called as scurvy occurs. This is characterisized by weakness, irritability, bleeding under the skin and in the joints bleeding gums, failure to heal or delay in the healing of wounds, anemia and weak bones.