Nicotine is extremely bad for you...I saw my mother paralyzed for 3years as a result of it. Your body increases calcium production in order to counter vein contractions caused by nicotine, thus hardening the walls eventually resulting in aneurisms/aka strokes. My father inlaw has 6 arteries bypassed after they collapsed from beein perfectly healthy- result from nicotine. It kills more people than Tar and other chemicals in cigz, just not always noted as heart attacks and strokes happen due to other causes aswell. I'm just forced to scale down slowely in order to not relapse back to cigs...But ultimately I hate nicotine.
Actually, studies have show that in the quantities available in vaping, Nicotine is fairly safe and actually has some benefits too. To put it in perspective, too much sugar can be very harmful - basically it's a matter of quantity, and staying below some level is generally safe. Just have a look at the news section on the site for some very interesting articles.
But quitting nicotine is, in the end, a personal decision and if that is your intent then best of luck with it...still, just don't rush it and risk going back to the cigs