When I was younger, my parents always told me, "Candy will rot your teeth!" Using the best deductive reasoning a precocious five-year-old could muster, I came to the conclusion that couldn't be true. I mean, how could something that tastes so good corrode me from the inside out? Again, I was five so that logic seemed pretty sound at the time. It wasn't until much later down the line that I learned that virtually everything that tastes good is bad for you. Apparently, that sentiment is most true when it comes to sour candies.
Your teeth's enamel starts to wear away when you start munching on anything more acidic than a 4 on the pH scale. To give you some comparison, water has an acidity of 7 and battery acid is at a 1 on the pH scale. The acidity of your average candy of even the mildest of tangingess start around a 3 to a 2.5 of the pH scale, and I'm not talking about the really sour stuff here, I'm talking about Skittles and your typical gummy bear.
The insane thing here is that some of the heavy hitting sour candies like Wonka Fun Dip powder and Altoid Sours measure up around a 1.8 and 1.9, respectively. WarHeads Sour Spray tops the charts with a 1.6 pH level, a mere 0.6 pH away from battery acid.
I feel like what my parents said to me all those years ago should have been amended to "(Sour) candy will rot your teeth!" At least then, the advice they gave me would have been more accurate when I chose to ignore it.