One of the more interesting bits of trivia about nicotine and caffeine is it is the mode of delivery that makes nicotine so addictive. If you smoked caffeine it would be as addictive as nicotine. Given we now have vaping it should be possible to smoke caffeine - I haven’t looked, but I would not be surprised if someone out there is selling smokable caffeine.
Sure - the harm is is going to be greater when you add in all the other nasty compounds in tobacco smoke.
It in not only smoke that is harmful as people who chew tobacco suffer an increase in mouth cancer. While vaping should have a lower risk than smoking, it is not risk free. Since it is so new we won’t know for sometime how dangerous it is.
The problem with cigarettes is not just that they kill you a little bit sooner, but that they cause many years of life of reduced quality. There's a bunch of stuff like COPD or stroke that don't always kill smokers but do make their lives much less pleasant.
I'm not sure if you were making a distinction between vaping and smoking, but I checked and there is indeed vapeable caffeine (plus taurine and flavoring.) I feel weird dropping a link, but search "Energy Shisha" if you're interested.
One of the more interesting bits of trivia about nicotine and caffeine is it is the mode of delivery that makes nicotine so addictive. If you smoked caffeine it would be as addictive as nicotine. Given we now have vaping it should be possible to smoke caffeine - I haven’t looked, but I would not be surprised if someone out there is selling smokable caffeine.