Nabeel AlAteeqi MD, FRCPC and Johane Allard MD, FRCPC
University of Toronto, Toronto, ON.

Introduction
Zinc is one of the essential micronutrients, and plays an important role in human nutrition and health. In 1961, Prasad first recognized zinc deficiency as the cause of dwarfism and hypogonadism among iron-deficient adolescent Iranian village boys.^1,2

Zinc deficiency occurs in individuals and populations with diets low in sources of readily bioavailable zinc, such as red meat, and high in unrefined cereals that are rich in phytate. The elderly population is potentially vulnerable to zinc deficiency because of decreased intake of food energy, protein, vitamins and minerals, and increased intake of carbohydrates.^3,4

In this review, we discuss the importance of zinc to humans, as well as the causes, clinical features and management of zinc deficiency in the elderly population.

Importance of Zinc
Zinc is an essential mineral, present in most systems of the human body, and plays a role in stabilization of cell membranes, tissue regeneration and protein synthesis. It also serves as a structural component of at least 70 metalloenzymes. Examples of zinc metalloenzymes are carbonic anhydrase, alkaline phosphatase, alcohol dehydrogenase and zinc-copper superoxide dismutase.

In addition, zinc is needed for growth, normal development, DNA synthesis, RNA conformation, immunity, neurosensory function and other important cellular processes.