This Is What's Really In Coke Zero's Secret Recipe

Coke Zero's recipe is a closely-guarded secret. Tracking it down feels a bit like going undercover, but like any good detective, you've got to start at the beginning. 

Only two people supposedly know Coca-Cola's secret formula (via Snopes), at least in theory, and at least until 2008. In 2008, Coca Cola amazed the world by leaking previously-unknown information about its formula. First, it contained spices from around the world. And second, its recipe had not changed in 122 years, or since 1886 when it was invented (via The New York Times). According to Snopes, the latter isn't entirely accurate, though. For 17 years, between 1886 and 1903, the recipe probably contained the fluid extract of coca, which has cocaine. Today, it contains a decocainized flavor essence of the coca leaf instead. 

In February of 2011, Coca-Cola's world came crashing down. This American Life, a public radio program in the United States, made international headlines by revealing a recipe they found in an old newspaper, and which they proved was probably the original recipe for Coca-Cola (via PR Newswire). Later that year, in a clear attempt to regain the mystery that shrouds the recipe, the company made headlines by moving its formula from a vault at SunTrust Bank in Atlanta, where it had been since 1925 (via World of Coca-Cola). Coca-Cola's not-so-secret recipe is now housed in the World of Coca-Cola in Atlanta, in a high-security steel vault that looks like something out of a James Bond movie. 

The urban legends surrounding Coca-Cola are mostly false. It's not true, for example, that you can dissolve teeth or clean up a crime scene using Coca-Cola. But Coke Zero has some surprising uses. Specifically, doctors can combine Coke Zero with polyethylene glycol to prep your bowel for a colonoscopy (via National Library of Medicine). 

Why? We don't really know. Unlike the original Coca Cola, nobody's found Coke Zero's likely recipe in a dusty newspaper. Maybe its mysterious, cleansing properties have something to Coke Zero's ingredients — carbonated water, caramel color, phosphoric acid, aspartame, potassium benzoate, natural flavors, potassium citrate, acesulfame potassium, and caffeine (via Coca-Cola). It could have something to do with that specific ingredient called potassium citrate, which is absent from other Coke varieties (via HuffPost) — interestingly, doctors have used it to treat kidney stones (via The American College of Cardiology). 

But even if Coke Zero is a godsend for people who may be concerned about the health of their bowels, that's not to say it's is good for you. Coke Zero's recipe also calls for acesulfame potassium, an artificial sweetener that researchers are concerned might affect your neurocognitive functions and that may be carcinogenic (via Science Direct). And, like other varieties of Coca-Cola, Coke Zero contains phosphoric acid, a corrosive used in fertilizers, detergents, rust proofing, and metal coating processes (via Science Direct).