Sensory Dysfunctions due to Trace Element Deficiencies and the Clinical Aspects

Among the trace elements known to be essential to human nutrition, zinc is typical in that the lack of it can cause sensory dysfunctions in human. It is known that a deficiency of zinc results in a wide variety of diseases with sensory (gustatory, olfactory, and visual) dysfunctions being only one type of them. In the present study, the focus is placed on the taste disorders as an example of a sensory dysfunction caused by trace element deficiencies; and on the etiological mechanism of the disorders that are associated with zinc deficiency. A reduced serum zinc level (below 70 g/dl) seen in cases of taste disorders has also been noted frequently in similar conditions that are putatively provoked by other causes (e.g., those caused by systemic or drug-induced dysfunctions). These findings suggest that zinc is likely to play a role in the development of many types of taste disorders. Supplementation by oral zinc preparations has been found to be effective in a number of double-blind tests on clinical cases with idiopathic or zinc deficiency-induced taste disorders, which substantiated the aforementioned