The real difference between 7UP and Sprite

While a can of 7UP has the same amount of calories as a can of Sprite and boasts the same all-natural, lemon-lime flavor, they're quite distinct from each other in a number of ways, starting with their histories (via 7UP and The Coca-Cola Company).

7UP was created back in 1929 by Charles Leiper Grigg. It's changed quite a lot since then, when the soda was marketed as Bib-Label Lithiated Lemon-Lime Soda (quite a mouthful, no?). The original formula included the mood-stabilizing drug lithium citrate in its formula, which is still used to treat bipolar disorder and other mood disorders to this day (via Gizmodo). Some even believe the "7" in 7UP refers to the atomic mass of lithium, although it could just be in reference to the drink's original seven ingredients. 

While this sounds a little crazy, it's not wholly dissimilar from the original Coca-Cola, which used coca leaves in its recipe, the source of cocaine (via Business Insider). In fact, the reason sodas were made with carbonated water is because it was believed to have medicinal properties, so the inclusion of medicine in soda wasn't all that hard to swallow at the time.

Sprite started as a competitor for 7UP

Sprite, on the other hand, never included a mood stabilizing drug in its formula, and wasn't even invented until 1959. It, like 7UP, had a much longer and clunkier name to begin with: Clear Lemon Fanta. Just two years after its formulation in West Germany, Sprite was introduced to the U.S. market to compete directly with 7UP (via Rock Hill Coca-Cola). It's owned by the Coca-Cola company. Today, 7UP is owned by Keurig Dr Pepper in the United States, and PepsiCo in the rest of the world.

Finally, there are the differences between the drinks themselves. When it comes to formulation, one distinction often pointed out is the salt. Sprite uses sodium citrate in its formula, while 7UP uses potassium citrate. However, when it comes to taste, it can be less clear cut. As evidenced by multiple Reddit threads, some people can taste clear differences in the level of sweetness, tanginess, and carbonation between the two drinks, while others simply cannot tell the difference between the two at all. Today, the market contains far more lemon-lime sodas and soft drinks than just Sprite and 7UP, including Sierra Mist, and Sun Drop.