Might be for some / in some situations. My „experiments“ worked without zinc so far. But maybe i should try it next time and see if it helps to get a success rate closer to 100 instead of just ~70%

The thing is as with Vitamin C, most supermarket products just have low doses. So to get an effect i recommend getting pure and high dosed preparates of both, each by itself.

I don't think you should use a very large dose of zinc. There's actually research on this, you could look it up. E.g., [1,2].

Some OTC products already contain vitC and zinc in proper amounts, e.g. Sambucol (not affiliated).

[1] https://en.m.wikipedia.org/wiki/Zinc_and_the_common_cold

[2] https://www.ncbi.nlm.nih.gov/pubmed/23775705

Might be better to talk about concrete numbers instead of "low/high/very large" doses :)

I would not take zinc in the same numbers as Vitamin C - but exactly therefor eI said I would take them apart, because, at least in the German and Spanish Market, you have combination preparates with 80mg Vitramin C and 5mg of Zinc - to achieve the effects I observed in myself you'd need 3x10 of these for the Vitamin C amount, whioch would be a lot of zinc which I would not recommend and have no experience with and no knowledge about the risks.

The articles seem to not agree in doses and helpfulness - one says it must be >= 75mg to actually do something, another that even 90+ mg doesn't do anything. And I believe to remember that already from 25mg/day you can get strange effects in the belly as side effects...