The butter flavor in microwave popcorn contains the chemical diacetyl, which has been linked to lung damage, according to CBS News.

In the past, factory workers have successfully sued popcorn manufacturers after getting ‘popcorn lung’ from inhaling diacetyl fumes all day. The official name for the life-threatening disease is bronchiolitis obliterans.

Now, it appears that diacetyl has caused lung damage for a consumer of popcorn who ate about two bags a day. Wayne Watson saw Dr. Cecile Rose after his lung capacity started to diminish. He was shocked when Dr. Rose asked him about his exposure to microwave popcorn.

‘It was about two bags a day every day for about ten years,’ said Watson.

After he stopped snacking on microwave popcorn, Watson, 53, lost 50 pounds and regained his lung capacity. He is now suing the Kroger grocery store chain that sold him the popcorn.

In the past year, the Flavor and Extract Manufacturers Association recommended a reduction of diacetyl in microwave popcorn. Since then, ConAgra (manufacturer of Act II and Orville Redenbacher brands) has announced that it will stop using diacetyl within a year. Other manufacturers are following suit, but to be safe, I won't be smelling the buttery aroma of microwave popcorn any time soon.