It was a Monday. Fourth-period calculus had just ended, and I was starving. I took out my wallet and saw that I had $3, enough money to get a sandwich. I quickly walked out of the south entrance, thinking whether I should get a bacon double cheeseburger or a triple. I took a few steps toward the crosswalk, a familiar daily route to the white truck where my lunch awaited. But to my surprise, it wasn’t there!

You are what you eat, as the saying goes. But do you know what you eat?

If someone handed you a bag containing a mixture of five to 10 chemicals with unfamiliar names, you probably wouldn’t think to eat from it — unless that bag was a bag of Doritos. As it were, I have looked at the ingredients list of such a bag. Besides the innocuous whole corn, corn oil, and salt, the list includes such esoteric items as disodium inosinate and disodium guanylate.