It's no secret that soft drink is bad for your teeth, but some are a lot worse than others. Turns out, citrus-flavoured soft drinks like Mountain Dew can have more teeth-rotting power than most colas. In this video from YouTuber Tom Scott, young scientist Chase from ScienceC explains the major differences between Mountain Dew and Coca-Cola using a classic science experiment. Chase drops some teeth — his sister's — into a bottle of Mountain Dew and Coca-Cola for 19 days, then measures their mass difference to see how much has been eroded.
Surprisingly, the Mountain Dew tooth loses twice the percentage of mass the Coca-Cola tooth does, despite the fact that Coca-Cola's pH makes it three times as acidic. Why? Because Mountain Dew has a higher "titratable acidity", which means it has more acid overall, and thus takes longer for the saliva in your mouth to dilute it. On top of that, the acid in Mountain Dew that gives it a citrus-y flavour is worse for your teeth as well. Mountain Dew has citric acid added to it, which is harder on your enamel than the phosphoric acid found in most cola beverages. So, if you're craving the sparkly tingle of a soft drink, maybe reach for a cola over a citrus drink. Or better yet, do your teeth a bigger favour, and grab a sparkling water.