I know many people say short term use of e-cigarettes have helped them that's great but I have to wonder about those who have no plans to stop. There seems to be a vocal battle between e-cig users and scientists each having their own claims about diacetyl. It's the famous fake butter compound for microwave popcorn that caused lung cancer in the workers who handled it. My dad has IPF and COPD two lung diseases from ye…
In any case, I doubt there's a very significant amount of people who've started ecigs who wouldn't have started cigarettes, and cigarettes are well known to cause lung damage.