The Effectiveness of Zinc Supplementation in Taste Disorder Treatment: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Abstract

Introduction. Food taste and flavour affect food choice and acceptance, which are essential to maintain good health and quality of life. Reduced circulating zinc levels have been shown to adversely affect the taste, but the efficacy of zinc supplementation to treat disorders of taste remains unclear. In this systematic review and meta-analysis, we aimed to examine the efficacy of zinc supplementation in the treatment of taste disorders. Methods. We searched four electronic bibliographical databases: Ovid MEDLINE, Ovid Embase, Ovid AMAD, and PubMed. Article bibliographies were also searched, which yielded additional relevant studies. There were no restrictions on the publication date to facilitate the collection and identification of all available and relevant articles published before 7 February 2021. We performed a systematic review and meta-analysis according to the PRISMA Statement. This review was registered at PROSPERO and given the identification number CRD42021228461. Results. In total, we included 12 randomized controlled trials with 938 subjects. The intervention includes zinc (sulfate, gluconate, picolinate, polaprezinc, and acetate), and the pooled results of the meta-analysis of subjects with idiopathic and zinc-deficient taste disorder indicate that improvements in taste disorder occurred more frequently in the experimental group compared to the control group (RR = 1.38; 95% CI: 1.16, 1.64, p = 0.0002 ). Zinc supplementation appears to confer a greater improvement in taste perception amongst those with chronic renal disease using zinc acetate (overall RR = 26.69, 95% CI = 5.52–129.06, p < 0.0001 ). The doses are equivalent to 17 mg–86.7 mg of elemental zinc for three to six months. Conclusion. Zinc supplementation is an effective treatment for taste disorders in patients with zinc deficiency, idiopathic taste disorders, and in patients with taste disorders induced by chronic renal failure when given in high doses ranging from 68 to 86.7 mg/d for up to six months.

Factors related to oral mucositis or dysgeusia in breast cancer patients undergoing fluorouracil, epirubicin, and cyclophosphamide therapy: A single-center, retrospective study

“…The results of the present study are consistent with this information. Previous studies have indicated that poor nutritional status hinders healing of in ammation [29][30][31], consistent with the present ndings. Maintaining good nutritional status is crucial in chemotherapy administration.…”

“…On the other hand, low serum zinc levels are associated with dysgeusia [29], and albumin levels have been reported to correlate with serum zinc levels [30]. The results of the present study are consistent with this information.…”

Associations between Zinc Deficiency, Taste Changes, and Salivary Flow Rates following Gastric Bypass and Sleeve Gastrectomy Surgeries

“…However, the single tablet serving for this supplement contains only 5 mg of zinc, an amount significantly less than the recommended daily intake according to the British Obesity and Metabolic Surgery Society (BOMSS, 2020), which suggests that zinc should be consumed at a ratio of 8–15 mg per mg of copper [ 19 ]. The maximum daily zinc consumption that is unlikely to have a negative impact on health is 40 mg for those over 19 years of age [ 20 ], and the role of zinc in the support of taste and the development of taste buds has been well-established in the previous literature [ 21 , 22 ]. These facts, taken together, suggest that the current zinc supplementation prescribed in clinical practice is insufficient to avoid zinc deficiency and thus to help prevent taste change following MGB.…”

The nutritional roles of zinc for immune system and COVID-19 patients

“…Zn also possesses antioxidant and anti-inflammatory properties that prevent damage to cells (28). Clinically, Zn supplementation is used for treating several infectious diseases, such as diarrhea, malaria, and COVID-19 (29). Of particular interest to many researchers is the fact that Zn is a nutrient required for maintaining a healthy sense of taste and smell (30).…”