Like twins, we tend to consider tobacco and nicotine as one-and-the-same. Let's separte them. Understanding Nicotine: Nicotine is a natural product of tobacco. When a cigarette is smoked, it releases many chemical messengers- neurotransmitters- such as acetylcholine, norepinephrine, vasopressin, histamine, arginne, serotonin, dopamine, autocrine agents, beta-endorphin and other tongue twisters that are responsible for most of nicotine's effects. Effects that are, in fact, positive. Nicotine appears to enhance concentration, memory, alertness and arousal, reduces pain and anxiety, extends the duration of positive effects, and increases sensitivity in brain reward systems.
There is evidence that nicotine itself has the potential to prevent and treat Alzheimer's disease, has been shown to delay the onset of Parkinson's disease, has a mild laxative effect reducing symptoms of ulcerative colitis, and reduces the chance of breast cancer among women carrying the very high risk BRCA gene. Nicotine is unique in comparison to most drugs as its profile changes from sedative to pain killer to stimulant in increasing dosages. Therefore, when using the E-Cig, the effect upon your system will depend on how much you "puff" but if you'll follow the advice given by other members, you'll have no problem. Nicotine does not induce weight gain.
Contrary to popular belief, nicotine does not cause cancer and is not a known carcinogenic. In cigarettes, cancer is caused over a long period of time due to smoke inhalation and the burning of various carcinogenic chemicals. In fact, while tobacco and nicotine have been used for centuries, lung cancer was unknown until the invention of the machine rolled cigarettes in the late 19th century. The International Agency for Research on Cancer has not evaluated nicotine in its standalone form or assigned it to an official carcinogen group. And, technically, nicotine itself is not significantly addictive, as nicotine administered alone does not produce significant reinforcing properties. But beware the word "significantly;" a word often used in the political arena and therefore highly suspect. Of course we become addicted to E-Cigs if for no other reason than the pleasure derived from them. But, unarguably, and until the medical society proves otherwise, it's a far, far safer -and cheaper- addiction than cigarettes. Enjoy yourselves.