Everyone seems to be trying to make sense of why certain people are coming down with COVID-19 and others are not. This white paper suggests nutrition and immune support may play a role. The authors are a Swiss panel of doctors and professors who note the benefits of a diet rich in things like Vitamin C, Vitamin D, and Selenium to boost immunity and compliment the body's ability to prevent viral infections. I don't see a downside to their recommendations.
An expert panel has written a white paper with a set of recommendations regarding the diet and micronutrient supplement needs of the Swiss and wider European population in order to support immunity during the COVID-19 pandemic.