Turkey, Tryptophan and Thanksgiving Naptime: A Holiday Hoax?

Ah, holiday traditions. Every November, you and your family head to Grandma’s house and after strategically finding a seat as far away from your opinionated uncle as possible, everyone settles in for one of the most anticipated eating occasions of the year: Thanksgiving. After everyone has had seconds (or thirds) and somehow made room for pie, more often than not the post-meal activity is…a solid nap.

Since the dawn of time, people have been blaming this sleepy phenomenon on the humble Thanksgiving turkey and its tryptophan content. But is this finger-pointing unfair? What is it about this meal that makes our eyelids so heavy? Is it time to lay off the bird once and for all? Let’s investigate.

What is tryptophan?

Let’s back up for a second and define exactly what the proposed napping culprit is. Tryptophan is an amino acid, which are the building blocks of proteins. Whether your preference is dark or white meat, turkey is an excellent source of protein and contains tryptophan. This amino acid is a precursor for serotonin and melatonin, which are associated with sleep. 

Guilty verdict reached, right? Well, let’s not get ahead of ourselves. Yes, it’s possible that tryptophan could make us drowsy, but in order to do so, it would likely need to be consumed on its own, absent of any other amino acids. This is because after we eat, the amino acids in protein all compete for entry to the brain, where they’re used to make a variety of neurotransmitters and hormones. When there’s a traffic jam of other amino acids at the door, tryptophan’s odds of entry to the brain – where it’s converted to serotonin and melatonin – are slim.

Secondly, there’s nothing terribly unique about the tryptophan content of turkey because other meats like chicken and beef have nearly the same amount (about 265 to 300 milligrams of tryptophan per 3-ounce serving). And get this: ounce for ounce, foods like seeds, some soy products, and even mozzarella cheese have more tryptophan than a serving of turkey.

So, in earth-shaking Thanksgiving news: We can’t place all of the blame on turkey for our urge to take a nap.

But why can’t I resist the urge to fall asleep? Grandpa’s chair isn’t even that comfortable.

You’re probably drowsy because you ate just a little more than turkey during the meal. Between the stuffing, mashed potatoes, green bean casserole and – if you’re like our family – pierogies stuffed with cheese and more mashed potatoes, you’ve just eaten a lot of food. After all of this our bodies have to divert energy to where we need it most – our gastrointestinal tract. If you throw a few glasses of wine into the mix, alcohol can also lead us to nod off.  We’re also much more inclined to take it easy on ourselves on a holiday, a sort of “letting our guard down” from the usual workday resistance to taking a midday nap.

Case closed?

Between the large meal, having some time for relaxation, and maybe just a bit of being “too tired” to talk politics with your uncle, these accumulating factors can spell out a recipe for sleepiness. So the next time someone makes a lame tryptophan joke at the dinner table (and trust me, someone will), you can set the record straight with this info.

Let’s make this the year where turkey stops taking all the flack. In fact, it’s probably one of the healthiest things on our dinner plate with about 25 grams of protein per serving (about the size of a deck of cards). Given its iron, zinc, potassium and vitamin B content, we should give turkey the respect it deserves with a place of honor in our holiday meals!

Not sure what to do with your Thanksgiving leftovers? Check out our turkey sliders and turkey pizza recipes in our “Make Over Your Leftovers” video series.

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