Buzzfeed spoke to a few avid soda drinkers about their habits, with a few saying they sometimes have several sodas a day.
They weren’t initially aware of what the experiment was until they were asked back five days later.
Teeth had been placed in cups of dark-colored soda and left there for five days.
They first put on gloves, and then were asked to pull out whatever they found at the bottom of the cup.
“My teeth hurt just thinking about it,” said one person.