A viewer asks: “Is the presence or absence of normal levels of vitamin D a contributing factor in vulnerability to COVID-19?”

This is one of many factors involved with maintaining a healthy immune system. So to the extent there is a deficit, plugging that gap in coverage may make a significant difference in whether a person contracts the illness with regard to symptoms or perhaps has an ability to be infected but fight off the virus so it never becomes symptomatic, or even if symptomatic, has a lesser severity and a shorter period of suffering with ample vitamin D in the system compared to a deficit situation.