It seems like two things happen every Thanksgiving. First, everybody gets sleepy after indulging in a big meal. Then somebody blames it all on tryptophan, a chemical found in turkey that's reputed to have nap-inducing powers.
Not so fast, Oklahoma Medical Research Foundation President Dr. Stephen Prescott said. “Although tryptophan is a key ingredient in making a brain chemical associated with relaxation and sleep, it's probably not what is inspiring Uncle Jeff to take a nap on the couch.”
Turkey does contain tryptophan, an amino acid that's essential for producing serotonin, which regulates mood and can induce sleepiness. But a serving of the Thanksgiving bird doesn't contain any more of the amino acid than other forms of protein.
“The turkey coma is just a myth,” Prescott said. If anything, the culprit is probably sitting next to the main dish, he said. “Eating carbohydrate-rich foods like dinner rolls, mashed potatoes, and stuffing causes a chain reaction that ends with the creation of the sleep-causing chemical melatonin in the brain.”
So if you want to stay awake for afternoon football, don't worry about the turkey; just take it easy on the carbs. Indeed, the first Thanksgiving meal is thought to have consisted of more protein and fiber and less sugar and starch, with the colonists and native peoples sharing a feast that might have contained lobster, cod, bass, deer, rabbit, chicken, squash, beans, chestnuts, onions, leeks, dried fruits, honey, radishes, cabbage, carrots and eggs.