Has vitamin D supplementation been shown to be effective in preventing the flu?
Has vitamin D supplementation been shown to be effective in preventing the flu?
user
Here’s a paper about studies of vitamin D in the context of preventing the flu:  “Vitamin D and the common cold.”  If you read that paper, I can explain the main results to you.  I’ll wait for your response.
assistant
I read it, now what did you conclude from the results?
user