Dear Dr. Boli: I bought this juice at the supermarket because the label said “100% JUICE” in big letters. Now that I have it at home, I notice that it also says “plus added ingredients” in tiny type below the “100% JUICE,” and the ingredients list includes citric acid, ascorbic acid, and “natural flavors.” So what are we up to now? 107%? I don’t understand. I thought you couldn’t have more than 100% of anything. —Sincerely, Dr. Margaret A. Hamburg.
Dear Madam: You are dealing with a very different kind of mathematics from what you learned in school. This is marketing mathematics, and it is based not on calculation but on negotiation and intimidation. The marketers write “100% juice” on the label because they are allowed to do so under current government regulations, which specify that a beverage can be labeled “100% juice” even if it also contains citric acid, ascorbic acid, flavoring agents, and a dead camel. This permission was achieved by means of delicate negotiations and periodic threats, but in the end it was decided that the negotiated meaning of “100%” would be “mostly made up of the stated ingredients, with some allowances for boring ingredients that no one wants to read about.”