Zinc

 Zinc

About 2 to 3 grams of zinc are found in the body. Like iron, zinc is absorbed according to the body needs.

Functions

·           Normal growth and sexual maturation.

·           As part of an enzyme that transfers carbon dioxide from tissues to the lungs.

·           The production of insulin by the pancreas.

·           Synthesis of proteins.

·           Normal sensitivity to taste.

Sources

Zinc is widely distributed in animal and plant foods that are good sources of protein.

Meats, egg, liver, sea food, legumes, nuts, milk wholegrain and cereals are good sources.

People who eat a normal diet adequate in protein are not likely to develop zinc deficiency.

Requirements

Daily requirements of zinc are given below

Infants - 3-5 mg/day

Children - 10-15 mg/day

Adults - 15 mg/day.

During pregnancy and lactation - 20-25 mg/day.

Absorption and excretion

Zinc present in animal foods are well absorbed in the small intestine, especially from the duodenum. Zinc present in plant foods are poorly absorbed due to the presence of phytic acid which interferes with its absorption. Zinc is mostly excreted in the feces.

Deficiency

The diet that has low zinc level leads to dwarfism and retarded sexual development. Zinc deficiency leads to diminished sensitivity to taste (hypogeusia) and to a decrease in odour sensitivity (hyposmia).


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