Vitamin C (Ascorbic Acid)

 Vitamin C (Ascorbic Acid)

Vitamin C is also called as ascorbic acid (Fig. 8.12).


Functions

·           Vitamin C is essential for building collagen the connective tissue protein which cements the cells and tissues together. The effect of this material is to provide firm tissues of all kinds. This vitamin helps forming strong blood vessels, teeth firmly held in their sockets, and bones firmly held together.

·           It has a general antioxidant role, especially in the regeneration of oxidized vitamin E in membranes.

·           Ascorbic acid reduces the ferric ion (Fe3+) to ferrous (Fe2+) ion and thus helps in the absorption of iron. It is also essential for rapid healing of wounds.

Sources

Raw fresh vegetables contain vitamin C, but some foods are more outstanding than others. Orange, grape, lime and lemon are especially rich in vitamin C.

Requirements

Recommended amount of vitamin C for different age group is as follows:

Infants - 35 mg / day

Children - 40 mg / day

Adults - 45 mg / day

Pregnant women - 60 mg / day

Lactating women - 80 mg / day

Absorption and storage

Ascorbic acid is rapidly absorbed from the intestines and passed on through the portal vein to the general circulation. Liver and other organs and tissues have an optimal level of ascorbic acid. Excess intake do not increase further the optimal levels.

Deficiency

Severe deficiency of vitamin C leads to scurvy. This is characterised by easy bruising and hemorrhaging of the skin, lossening of the teeth, bleeding of the gums and distruption of the cartilages that support the skeleton.

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