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If an afternoon nap in front of a fire or a football game is a time-honored holiday tradition for you, you’re not alone. In fact, according to de-identified OURA member data, the number of “naps” logged increases by 7% after Thanksgiving.

But it’s not all the turkey’s fault. Turns out, feeling fatigued after a big meal can be chalked up to a number of factors, including carbs and alcohol. The good news: Simple tweaks and strategies can help stabilize your energy levels after a holiday feast. Keep reading to dive into the science behind this frequent phenomenon and learn what you can do to feel more energized after a big meal on any day.

Does Turkey Really Make You Sleepy? The Tryptophan Myth, Debunked

Many people blame the main character of a traditional holiday meal—turkey—as the culprit behind the post-meal sleepiness. It is true that turkey contains tryptophan, an essential amino acid linked to the production of neurotransmitters serotonin and melatonin, which can induce feelings of relaxation and sleepiness.

Although tryptophan might be part of the story, it’s not all the turkey’s fault. In fact, a typical serving of turkey (around 8 ounces) contains only 125 to 150 mg of tryptophan—not nearly enough to cause you to fall asleep, which research suggests would be about 1000 mg.

Alongside tryptophan, turkey contains many other amino acids that compete for entry into your brain. The catch: For an amino acid to pass through the blood-brain barrier, it requires transport on a carrier protein. But due to competition from the many other amino acids, it’s harder for tryptophan to find a transport carrier. Thus, it’s unlikely to raise levels in your brain.

The Real Reasons Why You’re Tired After a Big Meal

1. Simple carbs

Carbohydrates are plentiful at most holiday dinners—mashed potatoes, stuffing, sweet potato casserole, dinner rolls, and pecan pie. When you consume a lot of simple carbs like these, it triggers the release of insulin to help process the glucose (aka sugar) in your bloodstream.

If your body has more sugar than usual, it can cause a rapid insulin spike to uptake glucose. The sudden spike and drop in blood sugar that happens after eating simple carbs can lead to an energy crash, also known as reactive hypoglycemia, causing you to feel tired.

This insulin surge also leads to a relative increase in tryptophan in the bloodstream, allowing it to enter the brain. In the brain, tryptophan eventually converts into serotonin and melatonin, both of which are neurotransmitters that increase feelings of relaxation and sleepiness.

2. A drink or two

Alcohol acts as a sedative, which means it affects your central nervous system and can cause drowsiness. It can also impair the quality of your sleep later in the night, making you more tired the next day.

Combining alcohol with celebratory socializing, as well as relaxation time on the couch, can further intensify your post-dinner drowsiness.

3. A large meal

When you consume large amounts of food, your digestive system works in overdrive to process the meal. Your heart rate increases and your metabolism ramps up, both of which are energy-intensive processes. This can divert blood flow away from other areas, including your brain, leading to fatigue.

Additionally, eating a big meal stimulates the parasympathetic nervous system. This is your “rest-and-digest” branch of the autonomic nervous system. As you may expect based on the name, this part of your nervous system promotes relaxation and drowsiness. Maybe that’s why they call it comfort food!

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5 Tips to Prevent Fatigue

If you have the ability to take a power nap, go for it. (Just try to keep it earlier in the day to avoid impacting your sleep!)

However, parents with young children or people hosting the holiday dinner may not have the luxury of taking a post-meal nap. If that sounds familiar, implement these five tips at your next feast to help prevent post-meal fatigue.

1. Take a shot (of espresso).

A single espresso shot contains about 60 milligrams of caffeine—enough to perk you up, but for most people, usually not enough to impact your sleep. Plus, science suggests that post-meal caffeine may enhance digestion and relieve fullness. That being said, caffeine has a half-life of about five hours, so if you’re eating in the evening, skip it.

2. Pile up the protein.

Imagine dividing your plate into three sections, then fill each section with protein, veggies, and carbs. Eating a meal that’s high in protein can help you avoid a postprandial dip in energy, as protein can help you avoid the glucose spike and crash. One study found that people who ate a meal with at least 35% protein had lower post-meal blood sugar.

3. Head outside.

Grab the family and go for a walk around the block after your feast. A study found that a 30-minute walk substantially reduces the glucose peak, improving your glycemic response.

4. Sip smartly.

If you do want to consume alcohol, alternate a glass of water for every alcoholic beverage you consume.

5. Focus on sleep the night before.

Getting a solid night of shuteye the night before helps balance your mood, improve your energy, and lower levels of ghrelin—the hunger hormone.

The Takeaway

The post-feast crash is a predictable physiological response to excess, not a mystical holiday curse. By integrating these five science-backed habits—like smart protein intake and a quick post-meal walk—you’re not just fighting fatigue; you’re actively managing your metabolic health.

This story* was produced by OURA and reviewed and distributed by *Stacker.