While eating healthy diet aids in the body's ability to fight COVID-19, it is unclear if vitamin supplements can help against COVID-19.
"While no foods or dietary supplements can prevent or cure COVID-19 infection, healthy diets are important for supporting immune systems. Good nutrition can also reduce the likelihood of developing other health problems, including obesity, heart disease, diabetes, and some types of cancer," the WHO said.
As far as vitamin supplements are concerned, there is a lack of conclusive evidence that indicates vitamin supplementation can play a significant role in the fight against COVID-19. A study conducted by researchers at Swansea University in August 2020 stated, "It would be unjustified to claim that vitamins are the answer to the coronavirus pandemic, but it would be fair to say that there is emerging evidence that they may play a role in either preventative measures or supportive therapy in established respiratory infections and intensive care settings. The physiology, pharmacology, and basic science behind vitamins A to E does allude to potential benefits that warrant further investigation and completion of the clinical trials."
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19 including symptoms, prevention and available treatment, please refer to the World Health Organisation or your national healthcare authority.