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Updated: May 20, 2026
13:04
Atomic Absorbance Spectroscopy to Measure Intracellular Zinc Pools in Mammalian Cells
Published on: May 16, 2019
The accuracy of the Zinc Taste Test method
1School of Health & Human Sciences, Southern Cross University, Lismore, NSW, Australia. tini.gruner@scu.edu.au
Summary
The Zinc Taste Test (ZTT) shows variable validity for assessing zinc status. While sometimes correlating with other tests, its reliability is questioned, indicating a need for more research.
Area of Science:
- Nutritional Science
- Biochemistry
- Clinical Diagnostics
Background:
- Diminished taste acuity (hypogeusia) is associated with zinc deficiency.
- The Zinc Taste Test (ZTT) is used by naturopaths but its validity is not well-established.
- Accurate assessment of marginal zinc status in humans remains a challenge.
Purpose of the Study:
- To systematically evaluate the validity of the Zinc Taste Test (ZTT) against other zinc assessment methods.
- To determine if the ZTT accurately reflects zinc status in different populations.
- To identify limitations and necessary improvements for the ZTT.
Main Methods:
- A systematic literature search was conducted for clinical trials comparing the ZTT with other zinc tests.
- Included studies reported full data from trials using the same sample population for ZTT and comparative zinc tests.
- Three studies met the inclusion criteria, involving patients with food intolerance and pregnant women.
Main Results:
- One study showed moderate correlation between ZTT and sweat zinc in food-intolerant patients.
- Two studies in pregnant women showed high congruence (70-100%) between ZTT and serum zinc initially, but varied results with leukocyte and cord blood zinc.
- Study III found no significant correlation between ZTT and other zinc measures but noted differences in pregnancy outcomes between ZTT tasters and non-tasters.
Conclusions:
- The ZTT's validity is questionable due to inconsistent results and methodological variations.
- While zinc deficiency impacts taste, it doesn't explain all hypogeusia cases.
- Current laboratory zinc assays may lack sensitivity, and no definitive sensitive and specific test for marginal zinc status exists.
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