I don't think the nicotine is the most fatal ingredient in cigarette smoke. The carcinogens created during the burning and drying process are much more dangerous. This does not mean nicotine is not addictive though.
Nicotine originally was added to cigarettes to improve the flavor. The addictive property was unknown at the time. People smoking predates the introduction of nicotine in cigarettes.
smoking made me lose so much friggin weight, it made me so i was never hungry.. i could go days without eating,.. i deteriorated to like 160 lbs... it sucked hard