Rather than sifting through massively multivariate data from epidemiological studies, better to see what vitamin D actually does at the molecular level. Huge li

Rather than sifting through massively multivariate data from epidemiological studies, better to see what vitamin D actually does at the molecular level. Huge literature on this. For instance, it doesn't 'seem' to modulate the immune system. It does. Start from there and then see how these reactions are attenuated. Can best advice can be extrapolated from this: The people who took Vitamin D supplements consistently for a year before being hospitalized did better because people who can do anything consistently for a year will do better - this selects for high-conscientiousness people who care a lot about their health and have good relationships with their doctors - though one might say 'Anything?'.