Every couple of months, a 21-year-old Chicagoan named Erynn Nicholson will scoop some vanilla ice cream into a bowl, crumble a fistful of Ruffles potato chips on top, and then mix it all together. Then she’ll call or text her mom. "I always let her know I’m eating our snack,” she told me.
Ice cream with potato chips has been their snack since before Nicholson was born—when she was still in the womb, her mom ate it regularly. The dish has carried special meaning for her for as long as she can remember, and while it’s not her “favorite favorite” food, “it's in its own little category,” she said.
That category, for many like Nicholson, transcends a mere flavor preference: Some people’s fondness for the foods their mother craved during pregnancy can to them seem predestined, taking on an almost sacred status in the mother-child relationship. Research hasn’t identified a direct causal link between the diets of pregnant women and the lifelong food preferences of their children, but exposure to certain flavors in the womb is one factor, among many, that can shape what people like to eat.
"Your sense of taste and smell is developed in utero,” says Julie Mennella, of the Monell Chemical Senses Center, in Philadelphia. “What the mother eats, a lot of [the flavors]—the garlic, vanilla, carrot, anise, a whole host of different flavors—are transmitted through the bloodstream and flavor amniotic fluid … If a baby has experienced a flavor in utero or in breastmilk, they prefer it more." Fetuses can get a lot of exposure to whatever flavors their mother recently tasted—near the end of a pregnancy, they can swallow almost a liter of amniotic fluid a day.