If you look at long term effects of snusers and people who use nasal snuff; it's pretty difficult to find any measurable negative health outcomes.
FWIIW the nicotinic hypothesis may not prove to be correct with respect to C19; Sweden will be a great test case, as there are more snus users than smokers there.
[1] https://academic.oup.com/carcin/article/30/3/506/2476826
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4430096/ -for example; too many papers to list
.. or snuff! Which I think is one of the most elegant ways of delivering nicotine to your body
My experience of it decades ago was anything other than 'elegant', unless having one's face scrunch up like a bulldog pissing on a nettle before exploding into a sneezing fit can be considered 'elegant'.
* we had a deal with our English teacher - my Swedish friend would supply him with little snus bundles, and we'd all get to sit in class using it ourselves. As a 17 year old, I thought it was the coolest thing, 'getting away with smoking in class with the teacher', even if i thought the actual process was utterly, utterly disgusting :)
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I do feel like I should be wearing a powdered wig when I indulge in the stuff. Blowing my nose brings me down to earth; it's pretty gross!
https://www.verywellmind.com/cigarette-additives-2824737
Perhaps the additives are keeping COVID-19 patients alive by supporting breathing in difficult circumstances? There are hundreds of additives so figuring out if any of them help would be difficult:
https://ec.europa.eu/health/scientific_committees/emerging/d...