It’s Thanksgiving in the U.S. The dining room table is overflowing with all the trimmings — mashed potatoes, sweet potato casserole, stuffing (or dressing), cranberry sauce, dinner rolls and of course, the star of the show, the glistening, golden turkey.
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You tuck into a full plate, excited and overwhelmed by all the wonderful food at your fingertips. Thank goodness you wore your stretchy pants — you’re going to need them.
Whether you clean your plate or leave a few forkfuls of Brussels sprouts behind, it doesn’t take long before you start to crash. You’re sleepy, sluggish, lethargic and feel like you can’t eat another bite (but wait, there’s three kinds of pumpkin pie, a pecan pie and Grandma’s cookies). Yikes.
Many of us attribute this sloth-like feeling to turkey (and more specifically, to tryptophan). But is that really true? Could other habits and behaviors also account for why we pass out on the couch after a big meal?
Registered dietitian Julia Zumpano, RD, LD, explains why turkey is just part of the recipe to feeling sleepy on Thanksgiving.
Tryptophan is known to cause drowsiness — and it can be found in turkey.
A serving size of turkey, which is about 3 ounces, contains anywhere between 250 milligrams to 300 milligrams of tryptophan.
So, what is tryptophan exactly? It’s an essential amino acid that’s used to make proteins. And you can only get tryptophan from the foods you eat.
Turkey isn’t the only food with tryptophan. Other foods that contain it include:
A key point of clarification, though? You’d have to eat a lot of these foods — including turkey — to feel drowsy.
So, why do you feel sleepy after Thanksgiving dinner or another big meal? You need to look at the whole picture.
“You might feel mildly tired after eating turkey,” says Zumpano. “But the tryptophan is not the only reason.”
Eating turkey is just one piece of the drowsiness puzzle when you eat a big meal like a turkey dinner. Here are some other reasons why you may feel sleepy after Thanksgiving dinner:
You probably tend to overeat during Thanksgiving dinner. And consider the types of foods you’re eating, says Zumpano.
“The meal typically contains large amounts of carbs (stuffing, potatoes, pie, desserts, rolls), which can spike your blood sugar initially,” she continues. “But then, your blood sugar levels crash or decrease, which leaves you feeling lethargic.”
To handle the large amount of food in your stomach, there’s a change in your blood circulation.
“Your bowels need more blood to digest the large meal, which may lead to less blood to your brain causing you to feel less alert,” explains Zumpano.
You don’t just have to contend with all the delicious food options. You may also feel like having a cocktail, glass of wine or beer with your meal.
“When you’re adding alcohol in the mix, that’s going to make you feel that more lethargic, more relaxed feeling on top of a big heavy meal,” Zumpano adds.
What can you do to combat that post-meal crash? Zumpano shares a few tips:
It can be tempting to load up your plate with all Thanksgiving dinner has to offer. But if you don’t like how you feel afterward, remember that you’re in control.
“If it’s a part of Thanksgiving that you don’t particularly enjoy, know that you can change the outcome,” encourages Zumpano. “You can take steps like watching how much you eat and drink exercising and getting enough sleep beforehand.”