The history of lettuce is not full of incident. Marco Polo did not bring back lettuce to Europe from Cathay (any more than he legendarily exported pasta). Marie Antoinette did not tell Parisians short on bread to eat lettuce instead. Although lettuce was certainly known to the Romans of Petronius’s day, it does not figure in the menu alongside honeyed dormice* at the banquet of Trimalchio in his Satyricon. But lettuce is not boring. Cultigens of Lactuca† sativa run the visual and physical gamut from bitter to peppery, green to red, tightly headed to loose-leafed, flat to curly. Needless to say, everyone knows about lettuce.
Still, there are a few recondite lettucisms a gastrotrivialist could dine out on. Wild lettuce (L. serriola) is a mild soporific. In ancient days it was considered a medicinal. Cultivated varieties will not give you a buzz unless you consume a desperate quantity. Our lettuces have had the downer bred out of them along with a lot of the wild-type bitterness.
You can cook lettuce by braising. But obviously the overwhelmingly most common form of lettuce consumption outside Asia is raw in salads. And the most popular nonsalad lettuce role is in sandwiches. Can we agree that the high point of human achievement in this popular category is the BLT? Of course, we can, which means that we share an affection for iceberg lettuce, that much-scorned-as-plebeian, crunchy leaf so indispensable as a companion to tomatoes, bacon, mayonnaise, and toasted white bread.
*Muscardinus avellanarius, a bushy-tailed, mouselike rodent fond of hazelnuts, as its name implies, the dormouse sleeps most of the day in a cocoonlike nest, just like the narcoleptic Dormouse in Alice’s Adventures in Wonderland. Petronius calls the little fellow glis.
†Lactuca is the classical Latin word for lettuce, used by Pliny and Virgil. It derives from lac, milk, because the midribs of its leaves yield a milky latex.