Vitamin D3: D3 & K2 and D3 Lozenge
From Ed Dratz, Professor at Montana State Univ. PhD in biophysical chemistry at Berkeley and 2 years postdoctoral research on molecular biology at MIT:
"Vitamin D3 is crucial for an active immune system, is a powerful antiviral, and high levels of vitamin Dare correlated with resistance to Covid-19. Vitamin D is also essential for active serotonin synthesis in the brain. People often have low levels of vitamin D. Some people absorb it poorly. We can generate vitamin D in our skin if we get sun exposure. People tend to be especially low in the winter months, if they don't get much sun exposure, or if they use a lot of sun screen. It is prudent to have your vitamin D level tested and to take vitamin D3 upplements if needed. "