Possibly for as long as there has been Thanksgiving, there has been an uncle or two passed out following the feast.
Traditionally, people have blamed tryptophan, an amino acid found in Thanksgiving turkey, but Morgan Pfiffner, a researcher at Examine.com who has a master’s degree in nutrition, says the bird gets a bad rap.
Tryptophan is used by the human body to make serotonin, one of the “feel-good” hormones that can calm and relax the body. But your average portion of turkey isn’t enough to have a major impact on keeping your eyelids open.
Many meats and other proteins have comparable amounts of tryptophan, in fact — and you’re usually not blaming your nap after steak night on the stuff.
So, it’s stuffing and everything else you’re putting in on Turkey Day, Pfiffner explained to ABC Audio.
The typical American Thanksgiving meal is loaded with carbs and fat, and all that releases a chemical called CCK (cholecystokinin). That not only signals to your brain that you’re full, but it makes you feel sleepy, possibly an ancient response to get your body to stop doing other stuff and focus on digesting.
And that’s not even counting the five beers you may have watching football.