Taz3cat, I've read everything I could find on nicotine and its consequences. I'm a nicotine addict, and I need to know what I'm doing to myself.
It's a drug, and like many drugs, it can have positive and negative health impacts. For many, it's a "normalizing" drug. It stabilizes a person, relaxing and stimulating at the same time. Many users concentrate better. Many with a variety of mental problems can benefit from nicotine.
The downside is serious, though. You clobber your "good HDL" cholesterol, ratchet up blood pressure and heart rate, initiate cataracts, compromise sexual prowess (prolonged use shrinks your testicles; a television show the other night revolved around that usually unmentioned side effect), etc. Yes, I read about nicotine. But mostly on sites like Science Daily, which posts every new and old study on items of science interest. I try to stay current, as new studies are being done all the time now.
If you find an interesting study, please post it for us.