Are e-cigarettes worse than the classic one? and what are its side-effects?

See below: E-cigarettes contain only nicotine vapor. They don't contain tobacco. Nicotine does not cause lung cancer or heart disease. It is the 200+chemicals produced when tobacco burns that cause disease. So E-cigaretts are much safer that tobacco. However, E-cigaretts can be just as addicting as tobacco and there is concern that they are being heavily promoted towards young adults>lead to smoking tobacco.