Taste disorder in hypo and hyperthyroidism.

Gustatory responses to the basic taste substances (sweet, salty, sour and bitter) were studied in hypothyroid and hyperthyroid subjects. The intensity and hedonic responses were evaluated using "category scaling" for 7 concentrations of glucose, sodium chloride, citric acid and quinine sulphate. The intensity and hedonic values decrease in hyperthyroidism for salt and bitter solution, and sourness is perceived as more unpleasant. In hypothyroid subjects intensity and hedonic value decreases for sweetness, the pleasant responses to salt and bitter increase, though intensity perception decreases for bitter solutions.