Why Does Turkey Make You Sleepy?

You may have noticed you are lying on the couch and ready to nap after eating your Thanksgiving meal. You also might be left wondering why the meal makes you tired, especially if you have eaten a lot of turkey. People often cite an amino acid called tryptophan as the cause of this Thanksgiving drowsiness.

Other factors may be at play, including high-fat and high-sugar dishes and alcohol. Read on to learn about the link between turkey and sleepiness and how you can prevent drowsiness after a big meal.

How Turkey Causes Sleepiness

It's common to feel tired after eating Thanksgiving turkey or deli turkey. Some evidence suggests that the drowsiness occurs because of a compound called tryptophan.

Tryptophan is an amino acid your body cannot produce, so you must get it from your diet. The compound plays a role in sleep regulation. Eating turkey seems to make you sleepy, but it turns out it does not actually contain much tryptophan.

"A pharmaceutical dose of tryptophan to improve sleep is around 5 grams [g] for adults, which is equal to 5,000 milligrams [mg]," Trista Best, MPH, RDN, a nutritionist based in Georgia, told Health.

About 3 ounces (oz) of turkey breast contains between 180–244 mg of tryptophan. You would have to eat about 61–84 oz of turkey to get 5,000 mg of tryptophan. That means it's very likely that tryptophan alone is not solely responsible for your sleepiness.

"Turkey isn't especially high in tryptophan—there's actually a bit more in chicken—so that post-Thanksgiving meal drowsiness is more likely due to overeating," Megan Wong, RDN, a dietitian at One Stop Nutrition, told Health. "That and the fact that you're overeating high-fat dishes. Research has shown that after a high-fat meal, an increased level of the hormone cholecystokinin (CCK) leads to drowsiness."

Cocktails you may have enjoyed throughout the day can also make you sleepy, Uma Naidoo, MD, a psychiatrist and author of "This Is Your Brain on Food," told Health. The same is true for carbs and refined sugars people typically eat in a Thanksgiving meal. These sugars can raise blood sugar, rendering you ready for a nap.

What Is Tryptophan?

Tryptophan is an amino acid. Dr. Naidoo added that tryptophan "helps support the healthy production of neurotransmitters including serotonin, which plays a role in producing the sleep-supporting hormone melatonin." This can explain why eating turkey makes you sleepy.

The compound has additional purposes beyond playing a role in sleep. "Tryptophan is required for a wide variety of functions in the body," explained Best. "It's necessary for metabolic functions that impact mood, memory, visual cognition, and comprehension." Research has also found that increasing the intake of tryptophan from foods can result in significantly less anxiety, depression, and irritability.

Turkey is probably the first food that comes to mind when talking about tryptophan. You'll also find tryptophan in a lot of protein-rich foods, such as:

• Cheese
• Chicken
• Egg whites
• Fish
• Milk
• Peanuts
• Pumpkin seeds
• Sesame seeds
• Soybeans
• Sunflower seeds

"Aside from turkey, nuts are also rich in tryptophan, especially pistachios, cashews, almonds, and walnuts," said Wong. Nuts might be adding to your drowsiness if they are part of your Thanksgiving spread.

How To Prevent Drowsiness

Most Americans sit down for a large meal featuring turkey as the main course on Thanksgiving. Chances are you'll be tempted to eat more than you would on a typical day. It's best to enjoy food and alcohol in moderation if you need to be awake and alert.

"To avoid post-meal drowsiness, it's important to not eat past your body's fullness," said Best. "Don't stuff yourself at the meal to the point of being uncomfortable. It's also important to make sure you are hydrated as this will help with energy, as well."

You may think that everyone is ready to fall asleep right away after eating turkey, given tryptophan's widespread reputation for making you nod off. Some people, in contrast, metabolize this amino acid differently than others.

"We all have highly unique microbiomes and biochemical profiles—especially when it comes to neurotransmitters and hormones—which influence how we digest and utilize the nutrients in food, as well as how they make us feel," said Dr. Naidoo. "Knowing this, it's likely that some of us may be more or less sensitive to the sedative effects of tryptophan."

How people metabolize tryptophan can have an impact on how quickly it takes effect. Dr. Naidoo suggested employing mindfulness while eating turkey so you can figure out your body's tolerance of the compound or lack thereof.

A Quick Review

You might be sleepy after eating a Thanksgiving meal, but it's not just the turkey itself that makes you drowsy. Turkey contains tryptophan, which plays a role in sleep. The amount, however, is not enough to make a you fall asleep.

The drowsiness after a Thanksgiving meal is more likely be due to eating a lot of high-fat and high-sugar foods. Monitor how much you eat and drink to avoid post-meal drowsiness.