Does the Tryptophan in Turkey Actually Cause Sleepiness?
How chemistry explains tryptophan and debunks the myth that eating turkey (which contains it) induces drowsiness on Thanksgiving.
© American Chemical Society; thumbnail © Africa Studio/Adobe Stock (A Britannica Publishing Partner)
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Transcript
SPEAKER: The holiday season is upon us. And nothing says holidays quite like consuming huge portions of food. Of course, the most colossal meal of all comes on Thanksgiving. After your third plateful of Thanksgiving fare, it might be convenient to blame the turkey as you groggily squeeze between your aunt and brother-in-law for a place on the couch.
One common belief is that a compound in turkey, known as tryptophan, makes people especially drowsy. But we're here to debunk this holiday myth. Tryptophan is one of the essential amino acids. Essential, because people have to get it from their food.
In other words, our bodies can't synthesize tryptophan on its own. There are 20 total amino acids that your body needs to make proteins. The body uses tryptophan to makes serotonin, a brain chemical that promotes feelings of well-being and relaxation. Serotonin is used in the body to make melatonin, which helps control the body's sleep and waking cycles.
With tryptophan so tied up in the production of these pleasurable sleep-inducing chemicals, it's no wonder it gets the blame for the bleary eye days after a Thanksgiving meal. In reality, tryptophan levels in turkey are too low to cause drowsiness. And they're actually lower than the levels found in chicken.
Another thing, when you're eating protein-rich foods like turkey, tryptophan has to compete with other amino acids to get into the brain. Here's the deal, when tryptophan is taken on its own, in certain doses and on an empty stomach, it can make you sleepy. But it's not to blame for making you lethargic on Thanksgiving.
It's actually the huge helpings of carbohydrates found in bread, yam, stuffing, and slices of pumpkin pie that cause the post-meal grogginess, not tryptophan. Calorie-wise, most people eat more in one Thanksgiving meal than they do over the course of an average day.
When you over eat, the body diverts blood to the stomach and the rest of the digestive system to deal with the overload. With the blood supply to the brain and the rest of the body reduced, you feel tired.
So if sleep catches up with you this Thanksgiving, why not put something else to rest-- the myth that tryptophan in turkey is behind the sleepy holiday haze. Instead, recognize that tryptophan is a building block and not a stumbling block.
[MUSIC PLAYING]
One common belief is that a compound in turkey, known as tryptophan, makes people especially drowsy. But we're here to debunk this holiday myth. Tryptophan is one of the essential amino acids. Essential, because people have to get it from their food.
In other words, our bodies can't synthesize tryptophan on its own. There are 20 total amino acids that your body needs to make proteins. The body uses tryptophan to makes serotonin, a brain chemical that promotes feelings of well-being and relaxation. Serotonin is used in the body to make melatonin, which helps control the body's sleep and waking cycles.
With tryptophan so tied up in the production of these pleasurable sleep-inducing chemicals, it's no wonder it gets the blame for the bleary eye days after a Thanksgiving meal. In reality, tryptophan levels in turkey are too low to cause drowsiness. And they're actually lower than the levels found in chicken.
Another thing, when you're eating protein-rich foods like turkey, tryptophan has to compete with other amino acids to get into the brain. Here's the deal, when tryptophan is taken on its own, in certain doses and on an empty stomach, it can make you sleepy. But it's not to blame for making you lethargic on Thanksgiving.
It's actually the huge helpings of carbohydrates found in bread, yam, stuffing, and slices of pumpkin pie that cause the post-meal grogginess, not tryptophan. Calorie-wise, most people eat more in one Thanksgiving meal than they do over the course of an average day.
When you over eat, the body diverts blood to the stomach and the rest of the digestive system to deal with the overload. With the blood supply to the brain and the rest of the body reduced, you feel tired.
So if sleep catches up with you this Thanksgiving, why not put something else to rest-- the myth that tryptophan in turkey is behind the sleepy holiday haze. Instead, recognize that tryptophan is a building block and not a stumbling block.
[MUSIC PLAYING]