Chewing tobacco is nastily harmful for a variety of reasons, but there too nicotine is mostly only harmful in that it is highly addictive: https://www.mayoclin

Chewing tobacco is nastily harmful for a variety of reasons, but there too nicotine is mostly only harmful in that it is highly addictive: https://www.mayoclinic.org/healthy-lifestyle/quit-smoking/in-depth/chewing-tobacco/art-20047428 https://www.mayoclinic.org/healthy-lifestyle/quit-smoking/in... Nicotine poisoning is possible, but not for adults at normal dosages. It's all the other crap your inhaling, sucking, or melting which is carcinogenic or otherwise directly harmful. Taking nicotine regularly isn't that healthy, but the reason nicotine is bad is really mostly down to its addictive nature.