A US teenager was recently reported to have developed the oddly named medical condition “popcorn lung” after vaping in secret for three years.

Officially known as bronchiolitis obliterans, popcorn lung is a rare but serious and irreversible disease that damages the tiny airways in the lungs, leading to persistent coughing, wheezing, fatigue and breathlessness.

The term “popcorn lung” dates back to the early 2000s when several workers at a microwave popcorn factory developed lung problems after inhaling a chemical called diacetyl – the same ingredient used to give popcorn its rich, buttery taste.