One of the symptoms of coronavirus is a violation or loss of taste. Patients with COVID-19 also complain of dry mouth due to impaired saliva secretion. Japanese scientists have found that oral symptoms in patients with COVID-19 are associated with zinc deficiency.

Taste disturbance may persist for up to one year after recovery from COVID-19. At the same time, how much taste sensitivity is impaired depends on the severity of COVID-19.

Impaired salivary secretion is common in patients with diabetes and chronic bronchopulmonary diseases and those who take antihypertensive drugs. Although some patients with COVID-19 may have comorbidities and medications, impaired salivary secretion occurs in a significant number of patients infected with coronavirus and lasts up to 8 months after recovery from COVID-19.

Since both oral symptoms coincide early in COVID-19 and persist after recovery, these events may share a common mechanism.

COVID-19 Causes Taste Disorders by Infecting Cells of Taste Buds and Salivary Glands

The ACE2 protein, which is abundant in taste buds and cells of the salivary ducts and glands, is responsible for the entry of SARS-CoV-2 into cells. Penetrating cells, SARS-CoV-2 damages them and therefore can cause disturbances in taste and secretion of saliva.

Damaged taste bud cells take weeks to multiply and restore function, while cells responsible for saliva production take 50 to 125 days. Therefore, taste and saliva secretion disturbances may persist after recovery from COVID-19.

Zinc is Essential for Taste Perception and Salivation

Zinc stimulates cell proliferation and differentiation, regulates inflammatory responses, and has antiviral activity. Zinc levels are an indicator of antiviral immunity. Zinc deficiency predisposes people to infectious and inflammatory diseases and increases the production of pro-inflammatory cytokines: interleukin-6, interleukin-8, and tumor necrosis factor. Zinc deficiency is associated with aging, malnutrition, hypertension, diabetes, and cardiovascular disease, all of which are risk factors for COVID-19.

Zinc is present in high concentrations in taste buds and salivary gland cells. Zinc is responsible for taste perception and salivary secretion, as zinc deficiency leads to reduced taste sensitivity and impaired salivation.

Viral infection and inflammation of the salivary glands leading to a change in the composition of saliva. Moreover, the shift in taste is associated with a difference in the rate of salivation and the concentration of salivary components, including zinc and zinc-binding protein.

Coronavirus Leads to Zinc Deficiency

Serum zinc levels in patients with COVID-19 are significantly lower than those without COVID-19 and healthy controls. At the same time, zinc levels are more reduced in patients with more severe and lethal COVID-19. Low zinc levels persist for 4 weeks after the onset of the disease.

Zinc Deficiency Is Part Of The Immune Response To Coronavirus

Zinc inhibits SARS-CoV-2 replication. A decrease in zinc levels promotes better binding of viral particles to the ACE2 receptor, but increasing zinc levels suppresses ACE2 expression.

Zinc is redistributed from the blood to the liver during infection-induced systemic inflammation, such as sepsis. Therefore, the concentration of zinc in other tissues and serum decreases. Treatment with antiviral drugs normalizes zinc levels.

Zinc deficiency is the body’s response to infection with coronavirus, not a factor that causes COVID-19. A decrease in serum zinc concentration is one of the immune response mechanisms. This mechanism suppresses viral replication, impairing the availability of zinc to the virus, and activates immune cells to destroy the infection.

A study by Indian scientists showed that high zinc levels are associated with mortality from COVID-19. Zinc overdose can lead to oxidative stress and tissue damage. To treat severe COVID-19, glucocorticoids are used, which suppress inflammation and reduce zinc levels. These facts warn against the self-administration of zinc supplements without a doctor’s prescription.

Conclusions

With COVID-19, zinc-deficient patients are at increased risk of complications, hospitalization, acute respiratory distress syndrome, and death. In turn, the coronavirus reduces zinc levels, which leads to disturbances in taste and saliva secretion.

Zinc supplements may prevent and treat COVID-19 by boosting immunity and inhibiting SARS-CoV-2 replication. Since zinc deficiency is associated with taste and salivation disorders, zinc supplements may reduce oral symptoms in COVID-19 patients and speed up taste recovery after coronavirus.

However, elevated zinc levels can lead to tissue damage in COVID-19. Therefore, zinc supplements should only be taken with a doctor’s prescription.

Useful article, necessary information? Share it!

Someone will also find it useful and necessary:

References

Our Telegram channel: