Background and Objectives: Disruption to taste and smell are common symptoms of COVID-19 infection. Current literature overlooks taste symptoms and tends to focus on the sense of smell. Persisting cases (>28 days) of taste dysfunction are increasingly recognised as a major future healthcare challenge. This study focuses on the severity and recovery of COVID-19 induced taste loss and association with olfactory symptoms, lifestyle, and oral health factors.
Materials and Methods: This study was a cross-sectional survey comparing 182 rapid taste recovery participants (≤28 days) with 47 participants with prolonged taste recovery >28 days. Analyses of taste loss in association with smell loss, age, sex, illness severity, diet, BMI, vitamin-D supplementation, antidepressants, alcohol use, smoking, brushing frequency, flossing, missing teeth, appliances, and number of dental restorations were conducted. Differences in the severity of the loss of sour, sweet, salt, bitter and umami tastes were explored.
Results: Both the severity and duration of taste and smell loss were closely correlated (p<0.001). Salt taste was significantly less affected than all other taste qualities (p<0.001). Persisting taste loss was associated with older age (mean ±95% CI = 31.73 ±1.23 years vs. 36.66 ±3.59 years, p<0.001) and reduced likelihood of using floss (odds ratio ±95% CI = 2.22 (1.15 – 4.25), p=0.047).
Conclusions: Smell and taste loss in COVID-19 are closely related although a minority of individuals can experience taste or smell dysfunction in the absence of the other. The taste of salt may be less severely affected than other taste qualities and future work exploring this finding objectively is indicated. The association of flossing with rapid taste recovery adds to the growing evidence of a link between good periodontal health and favourable COVID-19 outcomes.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Catton, G. & Gardner, A. 2022, 'Covid-19 induced taste dysfunction and recovery: association with smell dysfunction and oral health behaviour', Medicina, 58(6). https://doi.org/10.3390/medicina58060715