10 Foods High in Tryptophan That Aren't Turkey (And Do They Really Make You Feel Sleepy?)

As the holiday season approaches, many families are busy with meal planning and ordering their festive turkeys. Along with the surge in turkey sales, there’s also growing interest in one of its key nutrients: tryptophan. It's famously linked to the post-Thanksgiving dinner drowsiness, but is it the real culprit? Let’s dive deeper into this amino acid and see if it’s the reason why your uncle needs a nap after the feast.

What Exactly Is Tryptophan?

Tryptophan is a crucial amino acid and a key component for building proteins in the body. Out of the 20 known amino acids, nine—including tryptophan—cannot be produced by the body itself and must be obtained through diet. This is why they’re considered 'essential.'

Studies have shown that tryptophan plays a significant role in the gut-brain connection. It acts as a precursor to serotonin, a neurotransmitter vital for functions like sleep, hunger, pain perception, and emotional processing. Additionally, it helps produce melatonin, a hormone that regulates circadian rhythms, and assists the liver in synthesizing niacin (vitamin B3), which is crucial for energy metabolism and DNA production.

Does Tryptophan Really Make You Sleepy?

Tryptophan is often associated with sleep, and some research suggests that a diet rich in tryptophan may enhance sleep quality by boosting serotonin and melatonin. However, consuming a turkey dinner (or any other meal rich in tryptophan) doesn’t instantly make you fall asleep as we might expect. This is because other amino acids in the meal can interfere with the absorption of tryptophan. Foods often contain a variety of amino acids, which can reduce tryptophan’s sedative effects.

After a big, satisfying holiday meal with various foods, it's more likely that the feeling of sleepiness comes from increased blood flow to the digestive system, away from the brain, rather than the tryptophan content in turkey.

Tryptophan-Rich Foods

The daily recommended intake of tryptophan ranges from 250 milligrams (mg) to 425 mg. Here are some excellent food sources rich in tryptophan to include in your diet throughout the year.

1. Chicken

Turkey contains between 303 mg and 410 mg of tryptophan per pound, but chicken isn't far behind, with 238 mg to 256 mg per pound. Fun fact: White meat, like the breast, actually has more tryptophan than dark meat (thighs, legs, and wings).

2. Lamb Shoulder

Poultry isn’t the only source of tryptophan: Roasted lamb shoulder delivers 706 mg in a 6-ounce portion, which is 252% of the recommended daily intake. Pair it with brown rice, and you’ll add another 67 mg of tryptophan per cup.

3. Beef Steak

Skirt steak is another powerhouse of tryptophan: A 6-ounce portion delivers 636 mg, or 227% of the recommended daily intake. An unexpected source of tryptophan? Oranges! A cup of Valencia orange segments adds another 18 mg of tryptophan.

4. Pork

While some pork products are low in nutritional value (sorry, bacon), pork is actually a rich source of tryptophan. A 3-ounce portion of pork chops provides 314 mg. Pork is also high in selenium, a trace mineral important for thyroid and immune system health, which can be hard to obtain in adequate amounts from the diet. For healthier options, choose lean cuts, such as tenderloin or pork chops with minimal visible fat.

5. Oats

Although tryptophan is often linked to animal-based foods, there are several plant-based sources of this amino acid, including oats. A cup of cooked oatmeal contains between 97 mg and 147 mg of tryptophan. Oats are also an excellent source of soluble fiber, which aids in digestion and helps manage cholesterol levels.

6. Dairy

Dairy products, such as milk and cheese, are excellent sources of tryptophan, with the amount varying by type. Cheese provides around 91 mg of tryptophan per ounce, while whole milk offers a substantial 183 mg per cup, making it one of the top options. In comparison, 2% or reduced-fat milk contains 138 mg per cup.

7. Nuts and Seeds

Several nuts and seeds are excellent vegan sources of tryptophan. One ounce of pumpkin seeds contains an impressive 162 mg of tryptophan, while two tablespoons of peanut butter provide 74 mg. In addition, pumpkin seeds are high in alpha-linoleic acid, an omega-3 fatty acid that helps reduce inflammation in the body.

8. Soy

Soy-based foods like edamame and tofu are packed with tryptophan. A cup of cooked firm tofu provides an impressive 592 mg of tryptophan, while a cup of edamame contains 416 mg. Both tofu and edamame are also rich in fiber, promoting digestive health and a balanced gut microbiome. Additionally, they are high in potassium, an essential electrolyte that helps regulate heart rate and muscle function.

9. Fish

In addition to being fantastic sources of anti-inflammatory omega-3 fatty acids, salmon and tuna are also rich in tryptophan. Both canned tuna and fresh salmon provide an impressive 252 mg of tryptophan per 3 ounces. When selecting seafood, remember to consider sustainable practices. Take the time to learn how the salmon was caught or quickly research the canned tuna brand you’re considering. (Here’s more on how to shop for sustainably produced seafood—our oceans will appreciate it!)

10. Eggs

Eggs are a rich source of protein and vitamin D, and they also provide a significant amount of tryptophan, with one egg containing 77 mg. Furthermore, eggs are packed with carotenoids like lutein and zeaxanthin, powerful antioxidants that are known to support eye health.

Tryptophan is a vital nutrient with various health benefits. It is well-known for promoting better sleep, but its advantages go far beyond that. Regular consumption of tryptophan-rich foods can enhance brain-gut microbiome health, increase serotonin production, and assist in niacin synthesis, an essential B vitamin that supports overall well-being.

Whether you're following a vegan, vegetarian, or dairy-free diet, or have no specific dietary restrictions, there’s a food rich in tryptophan for everyone. In addition to aiding sleep, tryptophan plays a crucial role in several other health benefits. By incorporating a variety of tryptophan-rich foods into your routine a few times each week, you can support your brain-gut microbiome, boost serotonin levels, and help your body make niacin, a vital B vitamin.