Among the most time-honored Thanksgiving traditions, the propensity for guests to head directly from the dinner table to the couch ranks right up there with pilgrim hats, family football games, and drawings of turkeys that look suspiciously similar to the outline of a five-year old’s hand. Some people nap, some just stare vacantly at the T.V. for hours, but pretty much everyone attributes their post-meal grogginess to one source: tryptophan. Grandpas, moms, and third cousins alike got comfortable spouting off the name of the essential amino acid found in abundance in turkey.
But it turns out that whole tryptophan thing is a myth. As the nation gears up for the holiday, several newspapers have stories explaining that while turkey does contain tryptophan, the level is so low that you’d have to eat a 40-pound bird to feel its effect. See articles here and here for some related tidbits, but the best scientific explanation is probably in this piece in the LA Times.
So what’s the real culprit? Most think it’s the spike in insulin that results when we’ve stuffed ourselves full of carbohydrates. As a vegetarian who often finds herself on Thanksgiving staring down a plateful of white food—mashed potatoes, macaroni and cheese, crescent rolls, a mysterious “salad” involving marshmallows—I find comfort in the news that my post-meal haze is not a result of sympathy pains, but rather, a shared state of carb overload. After all, isn’t Thanksgiving about maintaining familial bonds?