THE DEBUNKER On May 8, 1886 in Atlanta, Georgia, two men tried to mix up a batch of a new pain reliever for their pharmacy. The result was so delicious they marketed it as a soft drink instead, and Coca-Cola was born. Coke turned 133 years old this month, but any brand that's been so beloved for so long is liable to accumulate its share of folklore. Take a brief, refreshing pause to correct your carbonated conjectures about Coke with Jeopardy!'s Ken Jennings.
The Debunker: Is Cola as Bad for Your Teeth as Drinking Battery Acid?
During my school days, we more than once had to witness the "experiment" where the teacher put pennies in Coca-Cola, and they got incredibly shiny. We were told that this is because the acids in the soda were dissolving the oxides on the penny, which is true. We were also told that you could put bones and tooth in Coke and they would melt away, because soda on your teeth is just like drinking battery acid. This is…not so true.
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Acidity is measured on the pH scale, on which neutral substances are a 7 and the strongest acid possible rates a 0. Soda pH varies between about 2.3 (Cherry Coke) and 4.6 (diet A&W root beer). Coke is quite acidic as beverages go: between the carbonic acid in the carbonation and the citric and phosphoric acid added for a biting flavor, it's slightly less acidic than vinegar or lemon juice (which have a pH around 2) but more acidic than other fruits (an apple, for example, is a 3.5). But battery acid, which is sulfuric acid, has a pH around 1.0. Many dental websites incorrectly state that Coke's higher pH means it's more dangerous than battery acid, but that's reading the pH scale upside-down. (Also, I'm not sure dentists should be giving kids the idea that the only down side to drinking battery acid would be that it would damage your teeth as much as Coke.)
Is Coke (or lemonade or cranberry juice or any sour drink) good for your teeth? No. Acidic foods and drinks can dissolve tooth enamel, especially if they have sugar in them to boot, as most soft drinks do. Dentists recommend cutting down on soda, brushing more, drinking soda with meals to blunt the effects of the acids, and drinking sodas quickly rather than nursing them for hours. The risks can be real: one 2010 case report cited a nine-year-old who spent two hours a day slowly drinking a single soda while gaming, which eroded his teeth away substantially. But for most of us, the low concentration of the acids in soft drinks mean that you can drink a Coke sometimes and still take care of your teeth. It would be hard to make the same claim about battery acid.
Quick Quiz: :Car batteries are sometimes called "SLI batteries" because of the three main things powered by their current. What three parts of the car do S, L, and I stand for?
Ken Jennings is the author of twelve books, most recently Planet Funny and co-hosts the most important podcast in human history, Omnibus. He's also the proud owner of an underwhelming Bag o' Crap. Follow him at ken-jennings.com or on Twitter as @KenJennings.
