The Science Behind: Turkey Making You Tired

Hungry yet? (Image Credit: Air Flight Cheap Tickets).

Every year, American families gather around a table filled with food to celebrate my favorite holiday. After listening to the usual political arguments — which you know no one is winning anytime soon — and stuffing your stomach to food baby status, you can’t help but feel exhausted. But does that delectable bird in the middle of the table have something to do with your drowsiness?

The worst part about Thanksgiving is when you can’t enjoy it to the fullest because you’re too tired or too stuffed (Image Credit: Giphy).

For many years, people believed that tryptophan causes this drowsiness. Tryptophan is an amino acid that can be found in turkey. It is used to create the B vitamin niacin, which is turned into serotonin — a brain chemical that is used to create melatonin, a hormone that helps control sleep and wake cycles.

Tryptophan is actually used as a natural sedative, so why wouldn’t tryptophan in turkey make you tired? The major difference is that as a supplement, tryptophan is isolated, but in turkey, there are many amino acids that make it difficult for tryptophan to do its thing (Image Credit: TheSubstanceReviews.org).

These all seem like good reasons for tryptophan to be the cause of that post-Thanksgiving-meal-drowsiness. However, tryptophan being in turkey isn’t that special. It’s also in other foods such as chocolate milk, red meat, eggs, nuts, cheese, soy, and fish, in sometimes the same amount as it is in turkey. Also, when tryptophan goes to the brain, it has a hard time crossing the blood-brain barrier to have an effect. To enter the brain, it must compete with other amino acids, and since tryptophan is a scarce and bulky amino acid, it must wait in line for a while to get carried across the blood-brain barrier. Because of this, only a small amount of the tryptophan gets through. But then, what causes the drowsiness?

Pies, stuffing, and mashed potatoes are the ones to blame (Image Credit: Giphy).

Turns out that it’s probably carbohydrates. Once carbohydrates are consumed, they trigger the release of amino-acid-suppressing insulin, which removes most amino acids from the blood. However, it misses tryptophan. Now, tryptophan can easily cross the blood-brain barrier and tire you out because it doesn’t have to compete with other amino acids to get across.

Eating lots of food in one sitting can also make you tired because it takes a lot of energy to digest all that delicious food, but don’t let that stop you (Image Credit: Giphy).

So, this year, instead of debating politics at the Thanksgiving table — because we both know there is no getting out of that mess — you can debate whether turkey makes you sleepy. Because tryptophan does cause sleepiness, but it can’t do it without carbohydrates!

Works Cited

Ballantyne, Coco. “Does Turkey Make You Sleepy?” The Scientific American, Nature America, 21 Nov. 2007, www.scientificamerican.com/article/fact-or-fiction-does-turkey-make-you-sleepy/. Accessed 12 Nov. 2017.

Chang, Louise. “The Truth About Tryptophan.” WebMD, 18 Nov. 2009, www.webmd.com/food-recipes/features/the-truth-about-tryptophan#1. Accessed 12 Nov. 2017.

Lewis, Tanya. “Thanksgiving Myth Busted: Eating Turkey Won’t Make You Sleepy.” LiveScience, Purch, 26 Nov. 2013, www.livescience.com/41543-thanksgiving-myth-busted-eating-turkey-won-t-make-you-sleepy.html. Accessed 12 Nov. 2017.

Mikkelson, David. “The Big Sleep: Does Eating Turkey Make People Drowsy?” Snopes, 6 June 2003, www.snopes.com/food/ingredient/turkey.asp. Accessed 12 Nov. 2017.

Schumaker, Erin. “Why Does Turkey Make You Tired?” HuffPost, Oath, 24 Nov. 2015, www.huffingtonpost.com/entry/why-does-turkey-make-you-tired_us_56533f62e4b0258edb3229b3. Accessed 12 Nov. 2017.

— Isabella S., Pennsylvania

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