Flavored e cigarettes are not harmless. Doctors are now seeing teens with permanent lung damage from vaping. In the U.S., a teenager developed popcorn lung after vaping in secret for three years. This Popcorn Lung (Bronchiolitis Obliterans): Causes & Treatment Doctors are warning about a rare but serious lung condition linked to vaping, known as popcorn lung (bronchiolitis obliterans). The disease causes permanent scarring in the lungs' smallest airways, leading to ongoing A Warm, Buttery Flavor and a Risk of Irreversible Lung Damage No, Vaping Doesn't Cause Popcorn Lung Let's Set the Record Straight Popcorn Lung: A Dangerous Risk of Flavored E Cigarettes American Lung Association