Diacetyl is frequently added to flavored e-liquid to enhance the taste. Inhaling diacetyl causes inflammation and may lead to permanent scarring in the smallest branches of the airways — popcorn lung — which makes breathing difficult.
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Vaping-related lipoid pneumonia is the result of inhaling oily substances found in e-liquid, which sparks an inflammatory response in the lungs.
I'm pretty sure inhaling hot air into your lungs still enflames them, and doing that repeatedly still increases cancer risk.
what about inhaling hot vaporized potent anti-inflammatory compounds?
https://www.hopkinsmedicine.org/health/wellness-and-prevention/what-does-vaping-do-to-your-lungs
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