and still you manage to provide 0 sources aside from “Yale and Harvard” and then resort to making fun of someone’s grandma or something. You then change your statement to “vitamin supplements have no impact” and “zinc plays a much more important”. The first one is differs from your original statement and the second one is completely irrelevant, since it seems to indicate that vitamin C does help, but not as much as zinc. I am not “looking” for anything, but when a person (like you) makes a claim, they’re deemed to back it up like I did with valid sources.How does Yale and Harvard research sound to you? And I should have been clearer, vitamin supplements have no impact on the immune system. Zinc plays a much more important role. The study by Pauling in 1970 did not hold to scrutiny at all. Countless universities around the globe have disproved his claims. Stop looking for confirmation bias because your grandma told you take vitamin C.