Nov
19
About That “Tryptophan Coma”…
“Turkeys get a bad rap.” — Jeanne Piga-Plunkett, registered dietitian at The University of Texas Health Science Center School of Public Health
My fellow Americans…
Many of you may be anticipating eating lots of turkey (along with assorted side dishes) this Thanksgiving holiday. This meal is often accompanied by a drowsiness and possible nap, which is blamed on the turkey.
It is sometimes called a “tryptophan coma”, because turkey is known to contain high levels of tryptophan — an essential amino acid necessary for making serotonin, a process which produces the hormone melatonin, which regulates people’s circadian rhythm (or the sleep-wake cycle). Serotonin also helps stabilize appetite, sleep, and mood, though just how much of a mood-enhancer it is is still inconclusive.
There are a couple problems with blaming it all on the turkey, though. For one, turkey isn’t the only food with high levels of tryptophan. For example, so do nuts, green soy beans, cow’s milk, cheese, eggs, beef, pork, chicken, firm tofu, and sockeye salmon, though they might not have quite the same drowsy effect. In fact, it isn’t the turkey alone that causes the drowsiness; rather, it’s the combination of turkey with large amounts of carbohydrates (e.g., in mashed potatoes, cranberry sauce, and pumpkin pie).
Y’see, these simple carbs break down into sugars which get absorbed into the bloodstream, thereby stimulating the production of insulin, which in turn helps clear the way for tryptophan to travel from the bloodstream to the brain. So, the carbs essentially pave the way for the tryptophan to do its thing.
Then, factor in the common strategy of eating very little until Thanksgiving dinner that day, then gobbling down more protein and carbs than usual — often too quickly for the brain to register that you’re full. As Shanley Pierce put it in her article for Texas Medical Center, “the body powers down into ‘rest and digest’ mode.”
Piga-Plunkett recommends instead to eat more slowly and smaller portions. Not that we’ll listen to her advice, of course. But, don’t blame the turkey alone.
WE are the ones who are gluttons for punishment — or, at least, for a nap and a few extra pounds.
Happy (Upcoming) Thanksgiving!
