Further to the nicotine discussion, I used it in lozenge form for several years, some of the science might be out of date in that article (CT mentions it as pre-workout but I think that the way it impacts makes it stimulate the brain but relax the muscles, meaning it’s good for thinking stuff not so much lifting stuff)
I’ve heard that nicotine can reduce insulin sensitivity so I stopped using it, plus my tolerance was too big, no issues stopping however. (Still occasionally partake of a good cigar).
Tobacco is still carcinogenic in whatever form consumed regardless of processing.