Research will not be conducted on the subject because it is unethical to subject any populace, however willing, to potentially harmful chemicals.
That said, when brown townyzed, the gasses put off by vaping are consistent with those from regular cigarettes that have been shown to cause cancer and other health defects. Formaldehydes, Monoxides, and other new chemicals introduced by the synthetic "flavors" added to the jelly used (which itself greatly increases the carbon monoxide and other chemicals).
You know what it has less of though? Nicotine. Nicotine itself, while addictive, is not nearly as harmful as all of the chemicals that get packaged into a standard cigarette. An all natural cigarette made from fresh tobacco with no preservatives is relatively safe, and can actually be medicinal. Tobacco had long been used as a treatment by Native Americans for gastrointestinal issues.
What happens however, is people, addicted to nicotine and used to the amount used to satisfy their addiction, end up having to smoke more, taking larger draws, in order to gain the same nicotine high. This means that per draw, they are inhaling even more carcinogens, which in that sense place e-cigs to be far worse in my opinion.
And that is not even to consider the unknown effects that some of these new untested chemicals introduce, scientists have already begun linking vaping to a condition known as "popcorn lung" which considering how recent the technologies introduction to society is, it concerns me that we are already seeing such detrimental effects.
If you have to smoke, use real cigarettes, but otherwise, I would suggest just stick to weed, it helps fight cancer as opposed to inducing it.
