Clinical and physiological investigations in patients with taste abnormality

Abstract

The cause of taste abnormality was investigated in 25 patients with decreased taste sensation (hypogeusia group) and 14 patients with abnormal taste sensation (dysgeusia group) by examining taste threshold, salivary flow rate, Candida cell culture, and laboratory examination of peripheral blood. The cause of hypogeusia was identified as iron deficiency in 7 patients, oral candidiasis in 6, hyposalivation (xerostomia) in 6, and psychiatric distress in 3, and could not be determined in 3 (idiopathic). Dysgeusia was associated with psychiatric distress in 8 patients, oral candidiasis in 3, drug medication in 2, and hyposalivation in 1. In the hypogeusia group, the decreased taste sensation generally corresponded with elevated taste thresholds, which decreased along with improvement of the decreased taste sensation in all except the 3 patients with psychiatric etiology and 2 of the 3 patients with idiopathic etiology. In contrast, no elevation or depression of taste thresholds were observed in the dysgeusia group, and the abnormal taste sensation did not disappear in most cases; however, drug-induced dysgeusia improved completely within 2 months after cessation of the drug administration. The serum copper and zinc levels were not decreased in any patient, but a decreased serum iron level was observed in 7 patients. Based on these results, it is concluded that abnormal taste sensation may be induced by many oral and systemic disturbances and that hypogeusia, which may be induced by deficiency of iron but not of zinc or copper, is usually accompanied by elevation of taste thresholds, while dysgeusia is not.

Xerostomia and medications among 32-year-olds

“…However, the strong association with the taking of pharmacological-dose iron supplements was unexpected and more difficult to account for. The symptoms of hypogeusia and burning mouth have been reported to be associated with iron deficiency [20,21]; these have also been related to xerostomia [22], and it may be that the association observed in this study was a manifestation of the condition being treated rather than of the therapy itself. This, of course, may also apply to the other observed associations: for example, was the xerostomia observed among those on antidepressants caused by the medication or the condition?…”

Zinc status and taste acuity in older Europeans: the ZENITH study

“…Zinc depletion may therefore be detrimental to extracellular synaptic but not intracellular activity related to taste perception. Most previous studies that have explored taste acuity in relation to zinc status have assayed serum to determine zinc status (Osaki et al, 1996;Tanaka, 2002;Watanabe et al, 2005). These conclusions are strengthened in being derived from both measures of longterm and short-term zinc status.…”

Human gustation and flavour

“…156,148 At this time, we know little of how drugs impact taste. Phantoms occur for several reasons, including oral yeast infections, 157,158 nerve damage (both mechanical and infectious) 159 -162 and head trauma.…”