Zinc is considered a trace element and it is the second most abundant trace element in the human body after iron. Zinc is an essential component for cell proliferation and differentiation, RNA and DNA synthesis. It also plays a big role in the regulation of the immune system. There is also a strong association between zinc deficiency and infectious diseases like malaria, HIV, pneumonia and tuberculosis. Zinc deficiency affects one-third of the world’s population. It is found that worldwide, zinc deficiency accounts for 16% of lower respiratory tract infections, and 10% diarrheal diseases.
It is worth noting that zinc influences every immunological event that occurs in the human body. Zinc deficiency increases the production of pro-inflammatory substances like Interleukin-6 that plays a significant role in COVID-19.
A study published in PLOS pathogens, a peer reviewed journal, recently gained prominence. It demonstrated inhibitory effects of zinc on coronavirus and arterivirus activity. Zinc is involved in several cellular processes and activity of enzymes required for protein synthesis. In cell cultures, high zinc concentrations inhibit replication of various RNA viruses like influenza virus and respiratory syncytial virus. The study revealed a robust inhibitory effect of zinc on the RNA synthesis of SARS-CoV and also arteritis virus inhibiting their replication.
Even though this study demonstrated the effects of zinc on coronavirus in cell cultures outside the human body, zinc may have similar effects inside our body. According to a study published in International Journal of Vitamin and Nutrition Research, zinc deficiency significantly increases death rate in septic patients. The article concluded that zinc is vital for proper native immunity to defend against infections.
Based on the available evidence, zinc is proven to boost native immunity to fight against viruses and bacteria. It is specifically proven to have inhibitory effect on coronavirus. Zinc supplementation may be recommended, especially in individuals prone to zinc deficiency.
Unlike other vitamins and minerals, zinc does not have a major storage depot in the body. Zinc deficiency occurs easily and rapidly, especially when a person is infected or under severe stress. Recommended daily intake of zinc depends on several factors such as age, sex, weight, and phytate content of diet. Those recommended values differ in each country. The US Food and Nutrition Board recommended intake of 11 mg/day and 8 mg/day for adult males and females, respectively.
Children, older adults, pregnant and lactating women, alcoholics and immunocompromised individuals are at a higher risk of zinc deficiency. These individuals should consider taking zinc supplementation to improve their immune status. Supplementation becomes more important in individuals affected by COVID-19 when zinc levels are rapidly depleted.
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