basically ^this^ is how I feel on your question

you are going to see responses from the zealots on both sides in here, mainly recognizable by them attacking each other with a constant demand for justifications on anything said on here from each other

but most of us are down the situational middle on questions like this. You are an adult and can do what you want but asking a vapers group what they think shows you have your doubts about it, I am not sure what your doubts are but if they are health related no one in here can tell you how safe or unsafe
vaping really is, no one knows what the long term effects of vaping are, for former smokers it is viewed as
harm reduction period.
Zealot wouldnt be my first choice to describe so-called vapers who encourage this kind of nonsense.
Air is made up of:
Nitrogen -- N2 -- 78.084%
Oxygen -- O2 -- 20.9476%
Argon -- Ar -- 0.934%
Carbon Dioxide -- CO2 -- 0.0314%
Neon -- Ne -- 0.001818%
Methane -- CH4 -- 0.0002%
Helium -- He -- 0.000524%
Krypton -- Kr -- 0.000114%
Hydrogen -- H2 -- 0.00005%
Xenon -- Xe -- 0.0000087%
Ozone -- O3 -- 0.000007%
Common sense and logic should tell you thats its far better to breathe these chemicals, ones that we've specifically adapted to over the course of tens of thousands of years, than it is to breathe a mixture of anything else. ....including 0 mg e juice.
Vaping for most of us is about harm reduction. That same common sense and logic dictates that inhaling 4 chemicals is better for us than inhaling over 4k of them (with 69 known carcinogens)
So just to clarify (mostly for the ever-increasing lunatic fringe on these forums)
Air > e-juice
e-juice > cigarette smoke
What you do with that knowledge is up to you.
And I will caution you that there are idiots who will argue the opposite side of any viewpoint, on any internet forum there is, no matter how wrong or far from the actual truth they are, and often in direct contradiction to that forums stated purpose, just for the sake of argument.
Sadly, a couple have already chimed in here.