What plants have L-tryptophan?

January 3, 2026 •

4 min read

Tryptophan is an essential amino acid that the human body cannot produce on its own, making dietary intake vital for creating mood-regulating serotonin and sleep-inducing melatonin. Fortunately, many diverse plant-based foods contain L-tryptophan, allowing individuals to naturally support their mental and physical well-being through diet.

Quick Summary

Several plants, including seeds, nuts, legumes, and nutrient-rich fruits and vegetables, contain essential L-tryptophan to support the body's production of serotonin and melatonin for mood and sleep regulation.

Key Points

Seeds are potent sources: Chia, pumpkin, and sesame seeds are exceptionally high in L-tryptophan and easy to add to meals.
Carbs aid absorption: Consuming plant-based tryptophan with carbohydrates helps the amino acid cross the blood-brain barrier more effectively than high-protein animal sources.
Soy products are excellent: Soybeans, tofu, and tempeh are significant plant-based sources of L-tryptophan.
Tryptophan boosts mood and sleep: The body uses L-tryptophan to produce serotonin and melatonin, essential for regulating mood and sleep cycles.
Microalgae is a top source: Spirulina, a nutrient-dense blue-green algae, is an excellent vegan source of tryptophan.
Combine diverse plant sources: To maximize benefits, incorporate a variety of plant foods into your diet, including nuts, seeds, legumes, and certain fruits.

Seeds: Concentrated Powerhouses

Seeds are some of the most potent plant-based sources of L-tryptophan, offering a concentrated nutritional boost that is easy to incorporate into daily meals. Their versatility makes them an excellent addition to everything from breakfast cereals to salads and baked goods.

Pumpkin Seeds: These lead the pack as an excellent source, providing a significant amount of L-tryptophan per serving. They are also rich in magnesium, a mineral crucial for nerve function and sleep.
Chia Seeds: In addition to L-tryptophan, chia seeds are full of fiber, omega-3 fatty acids, and other minerals, contributing to overall health.
Sesame Seeds: Whether whole or in tahini form, sesame seeds offer a notable amount of L-tryptophan. They are also packed with calcium and antioxidants.
Sunflower Seeds: Dry-roasted sunflower seeds provide a good dose of L-tryptophan and healthy fats, making them a nutritious snack.

Nuts: A Delicious Source of Amino Acids

Nuts are not only a great source of healthy fats and protein but also contribute substantially to your L-tryptophan intake. They make for a convenient snack or a crunchy addition to many dishes.

Cashews: A favorite for many, cashews are a top nut source of L-tryptophan.
Almonds: These nuts are known for their vitamin E and magnesium content, along with a healthy serving of L-tryptophan.
Walnuts: Rich in omega-3 fatty acids and antioxidants, walnuts also contain L-tryptophan, supporting both brain health and mood.
Peanuts: Technically a legume, peanuts and peanut butter are commonly grouped with nuts and offer a good source of L-tryptophan.

Legumes and Soy Products: Versatile Protein Sources

Legumes and soy products are foundational to many plant-based diets and provide a reliable supply of L-tryptophan. They are incredibly versatile and can be used in countless recipes.

Soybeans: Raw soybeans are one of the richest sources of L-tryptophan among legumes.
Tofu and Tempeh: These fermented soy products are excellent for vegans and vegetarians looking to boost their L-tryptophan levels.
Lentils and Chickpeas: These staples are good sources of L-tryptophan and other essential nutrients, perfect for soups, stews, and salads.

Fruits and Vegetables

While generally lower in protein, certain fruits and vegetables can still contribute to your daily L-tryptophan intake and contain complementary carbohydrates that assist with its absorption.

Bananas: Containing L-tryptophan and healthy carbs, bananas are a popular choice for supporting sleep and mood.
Pineapple: This tropical fruit offers L-tryptophan alongside beneficial enzymes.
Spinach: A leafy green known for its high nutrient density, spinach also contains L-tryptophan.
Kale and Watercress: Other leafy greens like kale and watercress provide L-tryptophan and a host of vitamins and minerals.

Comparison of Plant-Based Tryptophan Sources

To help you maximize your intake, here is a comparison of various plant sources and their typical L-tryptophan content per 100g, based on available data.


Source	Tryptophan (mg per 100g)	Notes
Spirulina, dried	920 mg	A potent microalgae source.
Soy protein isolate	1120 mg	A highly concentrated form.
Pumpkin seeds	576 mg	Excellent for a quick snack or topping.
Chia seeds	436 mg	Provides fiber and omega-3s as well.
Sesame seeds	388 mg	Found in tahini and versatile for baking.
Cashews	289 mg	Based on a typical 28g serving.
Soybeans, raw	240 mg	High content for a legume.
Lentils, raw	220 mg	A great source for soups and stews.
Oats, raw	230 mg	A breakfast staple for sustained energy.
Spinach, mature	34 mg	Best consumed in larger quantities.
Bananas	10 mg	Primarily aids absorption with carbohydrates.

Optimizing Plant-Based L-Tryptophan Intake

For optimal absorption and conversion to serotonin, consuming L-tryptophan from plant sources is often more effective than from high-protein animal sources. A balanced plant-based meal provides L-tryptophan along with complex carbohydrates, which trigger insulin production. This insulin helps muscles absorb competing amino acids, leaving a clearer path for L-tryptophan to cross the blood-brain barrier. This process is why combining high-tryptophan plant foods with other complex carbs, such as whole grains, is beneficial. A diet rich in a variety of these plants ensures a steady supply of this crucial amino acid and promotes overall mental well-being. The amino acid is heat-resistant, so cooking will not destroy its nutritional value.

Conclusion

Incorporating a range of plants rich in L-tryptophan is a natural and effective strategy for supporting your body's production of serotonin and melatonin. From seeds and nuts to legumes and specific fruits, the plant kingdom offers abundant sources for better mood, improved sleep, and overall mental health. Combining these with complex carbohydrates can further enhance absorption, providing a holistic dietary approach to well-being. To start, focus on incorporating a variety of these high-tryptophan foods into your daily meals. For more scientific detail on tryptophan, you can consult NIH Analysis of Tryptophan.

Frequently Asked Questions

Pumpkin seeds, chia seeds, and sesame seeds are some of the most concentrated plant-based sources of L-tryptophan.

The body converts dietary L-tryptophan into serotonin, a neurotransmitter that helps regulate mood, and consuming it with carbohydrates can improve absorption.

Yes, spirulina is a microalgae exceptionally rich in L-tryptophan, making it a powerful plant-based source for mood and sleep support.

While bananas contain some tryptophan, they are most helpful for sleep due to their carbohydrate content, which assists with the amino acid's uptake into the brain.

Yes, nuts such as cashews, almonds, and walnuts provide good amounts of L-tryptophan and are a healthy source of protein and fats.

Yes, a well-planned vegan diet can provide sufficient L-tryptophan through a variety of foods like legumes, seeds, nuts, and certain fruits and vegetables.

In addition to mood and sleep regulation, L-tryptophan supports overall well-being, cognitive function, and can help with anxiety and stress management.

No, L-tryptophan is heat-stable and not water-soluble, so cooking plant foods like legumes or vegetables will not destroy this essential amino acid.