The letter to the editor by Margaret Corasick in the June 30–July 6 issue correctly states the conventional wisdom that the recommended minimum amount of vitamin D to avoid clinical deficiency is about “5 to 15 minutes of sunshine two or three times per week on the face and hands.” However, the COVID-19 pandemic has led to new insight about this important vitamin, namely that most of us in the United States are deficient in vitamin D, and that vitamin D status is outcome determinative with respect to COVID-19 infection. It is very worthwhile to note that actual measurement of vitamin D status yields results different from the conventional wisdom and that living in a “sunny” country like Italy is no advantage.  My personal experience has borne this out. I live in San Diego, and I get plenty of sun because I garden. However, my measured level of vitamin D …