>>9101816On its own, nicotine (pure) is on the same scale of harmfulness as caffeine. Addictive? Yes, but generally not life threatening.
This is the main premise behind support for delivery methods that do involve pure or mostly pure nicotine, like patches or vaping.
When you introduce nicotine in tobacco as its natural form, it does change its harmfulness depending on the medium that it's carried by.
A tobacco leaf is more harmful to you than concentrate, but per lots of studies through the ages (which I cannot source) a smoking pipe, or a cigar, is MUCH less harmful than a cigarette. Provided you brush your teeth and practice good oral hygeine when using dip, snus, a cigar or a pipe you really have a quite minimal chance of developing cancers, and lung cancer is out or the question - somewhere on the scale of a 90% reduction in cancer rates compared to cigarettes.
In this fashion, if you ARE going to inhale smoke into your lungs, the composition of that smoke will be determined by the composition of the tobacco and its medium. So a cigarette's tobacco compared to leaves you grow on your own is a big difference when you consider growing methods, chemicals involved, processing and additives.
TLDR if you're gonna do it, do it traditionally or grow your own/use modern intake methods and you will probably be okay.