That is why they call it practicing medicine...
Since I have been vaping - my lung capacity has increased by over 18%. I can now go up and down the stairs several times without huffing and puffing (when my legs allow it of course). And while this probably not related to vaping, but could be - I now require minimal anit-allergy meds...
I've seen a number of people say that about their allergies. My allergies are so severe here though, it's impossible to tell on a daily basis. When I leave here, or go into a filtered air environment, it's all but gone.
My breathing has improved dramatically too, and that's with the allergy induced asthma. It infuriates me how vaping is vilified causing who knows how many people to never give it a chance.