1. Background COVID-19, a disease caused by a new type of coronavirus, has become a major global human threat that has turned into a pandemic. During this period, the role of the immune system has attracted people's attention. Some researchers identified some important nutritional considerations for the prevention and management of COVID-19 diseases (Yasemin Ipek Ayseli et al., 2020). Based on these studies, some "experts" and articles have urged people to buy supplements or eat particular foods to enhance their immune system.
