If you find yourself snoring on the sofa after a Thanksgiving feast, don’t blame the bird.
It’s an oft-cited factoid this time of year—an old canard, if you will: A heavy dose of an amino acid called tryptophan in turkey, they say, brings on the traditional after-dinner nap attack. But let’s nip this one in the bird: It’s all jive, turkey.
Tryptophan is an essential amino acid that facilitates the body’s production of serotonin, a brain chemical that helps make you feel happy, relaxed, and just plain ducky, thankyouverymuch. In the brain, serotonin also metabolizes into melatonin, a hormone that controls sleep.
Turkey is a good source of tryptophan, true, but so are plenty of other proteins, including meat, fish, eggs, cheese, and yogurt. Turkey contains no more tryptophan than other meats, and it actually comes in slightly behind chicken.
What’s more, just eating tryptophan isn’t enough to put extra tryptophan in your brain, where it counts. Protein-rich meals actually hinder the entry of tryptophan across the blood-brain barrier, by adding competition in the form of other amino acids.
Carbs, it turns out, are what prop the door of your brain open for the entry of feel-good tryptophan. So don’t blame the turkey for your postprandial plotz—thank the pie. Sweet dreams.