This is quite interesting. A person who had never smoked but started vaping experienced “a complete resolution of chronic tonsillitis”. His e-liquid contained VG and PG. In addition, a medical doctor, who had also never smoked but started vaping (VG but no PG), found that vaping cleared up a chronic nasal infection. Since it’s only two people one can hardly call it a study and the article states as much, saying that it could be coincidence. However – and this I didn’t know: “Some compounds in e-liquids may have antimicrobial properties” Miler and Hajek said that although the resolution of these infections could well be a coincidence, they could also be a result of the effect of some of the compounds found in vaping products. “The improvements cannot be attributed to smoking cessation or bactericidal effects of propylene glycol. The effect could be a coincidence, but it could also be related to bacteriostatic properties of glycerol, or to antimicrobial properties of nicotine and/or the zinc (II) complex of nicotine.” (my highlighting).” https://www.vapingpost.com/2019/03/07/study-vaping-helped-resolve-a-chronic-nasal-infection/ 7 March 2019 The above correlation could explain why I became very ill with flu every time that I stopped smoking (and at that time I wasn’t vaping). Even if one is vaping, the nicotine level which enters the bloodstream is less with vaping than it is with smoking. An acquaintance of mine stopped smoking about 8 months ago, started vaping and shortly thereafter she was hospitalised because one of her lungs collapsed. Her doctor told her it was because she had stopped smoking. Perhaps he was right, after all. Another acquaintance stopped smoking and stated vaping about a month ago and developed a respiratory infection. Coincidence? Or could there indeed be a causal relationship between the cessation of smoking and respiratory illness? Have you ever become ill soon after stopping smoking?