The role of nutrients to boost the immunity in the COVID-19 pandemic

Abstract

Summary. Regarding the current situation of the COVID-19 pandemic, in which there is no optimal cure, the functionality and efficiency of the immune response is the key factor in the defense against viral infections. Several nutrients, especially vitamins and microelements, are crucial for the immune system to function normally. Moreover, dietary supplementations of such nutrients have beneficial impacts on the immune responses to viral infections. Studies showed that after influenza vaccination, the supplementation of vitamins A and D boost the humoral immunity of pediatric patients. In patients with torque teno virus (TTV), dietary supplementation with high levels of zinc resulted in improved immunity. Also, high doses of selenium had positive effects on the immune response after influenza vaccination. Regarding the COVID-19, it is fundamental to demonstrate the data on increasing the immune response to viral infections. The present review paper principally subjects influenza-like viral infections. Nonetheless, other viral infections have also been taken into consideration. Therefore, practical recommendations on using nutrients for the prevention and therapy of COVID-19 are given.
 The aim of the study — to provide a complementary overview of the recently available scientific literature on the strategy of using nutraceuticals in boosting the immune system under the COVID-19 pandemic.
 Materials and Methods. The study uses publications of the world scientific literature on COVID-19 infection, in particular the causes and mechanisms of its development, treatment, complications and its consequences as well as the influence of different nutrients and nutrasuticals on the course of COVID-19. This review highlights the nutritional interventions to boost the immune response in the body during viral infections, especially considering the novel coronavirus pandemic
 Results. Immune system does great work in fighting foreign cells to protect the body from disease. Of course, when a global pandemic strikes the whole world, humans will feel anxious until they conquer it and be healthy. When the COVID-19 epidemic appeared, all sought to find a vaccine to counter this virus. Given a vaccine if provided, immune systems will need to adapt to the COVID-19-infected body. Proper nutrition can help in maintaining immune systems as the frontline of defense. Researchers believe that the deficiency of a particular nutritional element is implicated in the impaired immune responses. Nutrition principles based on using some dietary substances such as trace elements, vitamins, probiotics, and nutraceuticals may be helpful in the possible prevention and management of COVID-19. Control of the COVID-19 outbreak and future epidemics requires global efforts among clinicians, immunologists, nutritionists, researchers, veterinarians, and pharmacists. Also, public health awareness should be increased about the role of nutrition in eliminating the virus by boosting the immune system. Finally, better understanding the transmission dynamics, incubation period, and replications of COVID-19, along with finding and developing specific vaccines and therapeutics, will pave the way to end this infection soon.
 Conclusions. Despite the fact that the exact intracellular mechanisms of immunostimulatory action of nutrients have not been fully studied, there is much evidence of their beneficial effects on the body's immune system, as well as their proven antioxidant and anti-inflammatory activity. Nutrition plays an evidential role in the prevention and treatment of respiratory infections of varying severity. Adequate nutrition is even more important for low- and middle-income countries, where deficiencies in key vitamins and minerals expose people to greater morbidity and mortality. Low- and middle-income countries need to develop a strategy to ensure that the general population has access to optimal nutrition to strengthen the immune system, as well as to ensure a balanced diet during the treatment of patients with COVID-19.