Why?
Plain air-popped popcorn contains riboflavin, thiamine, and small amounts of iron and protein. As an occasional snack it is not harmful.
How much can dogs have?
A small handful of plain popped kernels occasionally.
What to watch out for
Butter, salt, oils, and flavorings make regular popcorn unsafe for dogs. Unpopped kernels can crack teeth or cause choking. Never give microwave popcorn with added flavoring.