What can high-tryptophan foods do for you?

What events can indicate a need for more high-tryptophan foods?

Food sources of tryptophan include red meat, dairy products, nuts, seeds, legumes, soybeans and soy products, tuna, shellfish, and turkey.

World's Healthiest Foods rich in
FoodCals%Daily Value












What is tryptophan?

Tryptophan is one of the 10 essential amino acids that the body uses to synthesize the proteins it needs. It's well-known for its role in the production of nervous system messengers, especially those related to relaxation, restfulness, and sleep.

How it Functions

What is the function of tryptophan?

Preventing Niacin Deficiency

Tryptophan has two important functions. First, a small amount of the tryptophan we get in our diet (about 3%) is converted into niacin (vitamin B3) by the liver. This conversion can help prevent the symptoms associated with niacin deficiency when dietary intake of this vitamin is low.

Raising Serotonin Levels

Second, tryptophan serves as a precursor for serotonin, a neurotransmitter that helps the body regulate appetite, sleep patterns, and mood. Because of its ability to raise serotonin levels, tryptophan has been used therapeutically in the treatment of a variety of conditions, most notably insomnia, depression, and anxiety.

Deficiency Symptoms

What are deficiency symptoms for tryptophan?

As an essential amino acid, dietary deficiency of tryptophan may cause the symptoms characteristic of protein deficiency, which include weight loss and impaired growth in infants and children.

When accompanied by dietary niacin deficiency, lack of tryptophan in the diet may also cause pellagra, the classic niacin deficiency disease that is characterized by the "4 Ds" —dermatitis, diarrhea, dementia, and death. This condition is very rare in the United States, however, and cannot occur simply because of a tryptophan deficiency.

Dietary deficiency of tryptophan may lead to low levels of serotonin. Low serotonin levels are associated with depression, anxiety, irritability, impatience, impulsiveness, inability to concentrate, weight gain, overeating, carbohydrate cravings, poor dream recall, and insomnia.

Toxicity Symptoms

What are toxicity symptoms for tryptophan?

High dietary intake of tryptophan from food sources is not known to cause any symptoms of toxicity. In addition, tryptophan has been given therapeutically, as a prescription medicine or dietary supplement, in doses exceeding five grams per day with no report of adverse effects.

However, in 1989, the use of dietary supplements containing tryptophan was blamed for the development of a serious condition called eosinophilia-myalgia syndrome (EMS), which caused severe muscle and joint pain, high fever, weakness, swelling of the arms and legs, and shortness of breath in more than a thousand people. In addition, more than 30 deaths were attributed to EMS caused by tryptophan supplements.

Many experts believe that the EMS was caused by a contaminant that was found in one batch of tryptophan sold by one manufacturer and occurred in only a small number of susceptible individuals. However, the United States Food and Drug Administration, the agency responsible for overseeing the dietary supplement industry, remained convinced that high doses of tryptophan were categorically unsafe. Since 1989, tryptophan has not been available as a dietary supplement in the United States.

To date, a Tolerable Upper Intake Level (TUL) for tryptophan has not yet been established by the Institute of Medicine at the National Academy of Sciences.

Impact of Cooking, Storage and Processing

How do cooking, storage or processing affect tryptophan?

There is no research showing problematic effects of cooking, storage, or processing on tryptophan levels in food.

Factors that Affect Function

What factors might contribute to a deficiency of tryptophan?

Vitamin B6 is necessary for the conversion of tryptophan to both niacin and serotonin. Consequently, a dietary deficiency of vitamin B6 may result in low serotonin levels and/or impaired conversion of tryptophan to niacin.

In addition, several dietary, lifestyle, and health factors reduce the conversion of tryptophan to serotonin, including cigarette smoking, high sugar intake, alcohol abuse, excessive consumption of protein, hypoglycemia and diabetes.

Drug-Nutrient Interactions

What medications affect tryptophan?

People taking the anti-depressant medications known as selective serotonin reuptake inhibitors (SSRIs) (including Prozac, Paxil, and Zoloft) should consult a physician before taking any other supplement or medication that also increases the amount of, or the effect of, serotonin, in the body.

Nutrient Interactions

How do other nutrients interact with tryptophan?

Vitamin B6, vitamin C, folic acid and magnesium are necessary for the metabolization of tryptophan. In addition, tyrosine and phenylalanine compete with tryptophan for absorption.

Because of this, some healthcare practitioners believe that food sources of tryptophan do not cause a significant enough increase in blood levels of tryptophan to produce therapeutic results, and that tryptophan must, therefore, be taken as a supplement to increase its blood levels.

Health Conditions

What health conditions require special emphasis on tryptophan?

Tryptophan may play a role in the prevention and/or treatment of the following health conditions::

Form in Dietary Supplements

What forms of tryptophan are found in dietary supplements?

Until 1989, tryptophan supplementation was standard practice in many countries around the world - including the United States - to treat insomnia, depression, and anxiety.

In the summer and fall of 1989, hundreds of people taking tryptophan supplements in the U.S. began to report the development of serious side effects including muscle and joint pain, high fever, weakness, swelling of the arms and legs, and shortness of breath, a constellation of symptoms that later became known as eosiniphilia-myalgia syndrome (EMS).

Upon investigation, it was discovered that nearly all of the cases of EMS could be traced back to a contaminant found in one batch of tryptophan produced by a Japanese manufacturer called Showa Denko K.K.

While all manufacturers of supplemental tryptophan synthesized this amino acid through a fementation process using bacteria, several months before the outbreak of EMS, Showa Denko K.K. had altered its process to make it more efficient and was apparently unaware that a toxic contaminant was being produced.

A few years ago, a new tryptophan-like supplement emerged in the U.S. marketplace. This supplement is called 5-hydroxytryptophan or 5-HTP. 5-HTP has been used in much the same way as tryptophan for the treatment of depression and insomnia, and for weight loss.

The reason is simple: the body ordinarily takes tryptophan and converts it into 5-HTP, and then takes the 5-HTP and converts it into serotonin. By taking 5-HTP, a person is taking a compound that is actually one step closer to serotonin than tryptophan.

Food Sources

Introduction to Nutrient Rating System Chart

In order to better help you identify foods that feature a high concentration of nutrients for the calories they contain, we created a Food Rating System. This system allows us to highlight the foods that are especially rich in particular nutrients. The following chart shows the World's Healthiest Foods that are either an excellent, very good, or good source of tryptophan. Next to each food name, you'll find the serving size we used to calculate the food's nutrient composition, the calories contained in the serving, the amount of tryptophan contained in one serving size of the food, the percent Daily Value (DV%) that this amount represents, the nutrient density that we calculated for this food and nutrient, and the rating we established in our rating system. For most of our nutrient ratings, we adopted the government standards for food labeling that are found in the U.S. Food and Drug Administration's "Reference Values for Nutrition Labeling." Read more background information and details of our rating system.
World's Healthiest Foods ranked as quality sources of
Food Serving
Cals Amount
Foods Rating
Chicken 4 oz-wt 187.1 0.41 128.12 12.3 excellent
Soybeans 1 cup cooked 297.6 0.39 121.88 7.4 excellent
Turkey 4 oz-wt 153.1 0.38 118.75 14.0 excellent
Tuna 4 oz-wt 157.6 0.38 118.75 13.6 excellent
Salmon 4 oz-wt 244.9 0.35 109.38 8.0 excellent
Lamb 4 oz-wt 229.1 0.35 109.38 8.6 excellent
Halibut 4 oz-wt 158.8 0.34 106.25 12.0 excellent
Shrimp 4 oz-wt 112.3 0.33 103.12 16.5 excellent
Cod 4 oz-wt 119.1 0.29 90.62 13.7 excellent
Sardines 3.20 oz-wt 188.7 0.25 78.12 7.5 excellent
Tofu 4 oz-wt 86.2 0.14 43.75 9.1 excellent
Spinach 1 cup cooked 41.4 0.07 21.88 9.5 excellent
Asparagus 1 cup raw 26.8 0.04 12.50 8.4 excellent
Dried Peas 1 cup cooked 231.3 0.18 56.25 4.4 very good
Kidney Beans 1 cup cooked 224.8 0.18 56.25 4.5 very good
Pinto Beans 1 cup cooked 244.5 0.18 56.25 4.1 very good
Navy Beans 1 cup cooked 254.8 0.18 56.25 4.0 very good
Black Beans 1 cup cooked 227.0 0.18 56.25 4.5 very good
Lima Beans 1 cup cooked 216.2 0.17 53.12 4.4 very good
Pumpkin Seeds 0.25 cup 180.3 0.17 53.12 5.3 very good
Lentils 1 cup cooked 229.7 0.16 50.00 3.9 very good
Wheat 1 cup cooked 151.1 0.09 28.12 3.4 very good
Cow's milk, grass-fed 4 ounces 74.4 0.09 28.12 6.8 very good
Eggs, pasture-raised 1 each 77.5 0.08 25.00 5.8 very good
Cheese 28.35 g 114.2 0.08 25.00 3.9 very good
Collard Greens 1 cup cooked 49.4 0.05 15.62 5.7 very good
Miso 1 tbs 34.2 0.03 9.38 4.9 very good
Turnip Greens 1 cup cooked 28.8 0.03 9.38 5.9 very good
Soy Sauce 1 tbs 10.8 0.03 9.38 15.6 very good
Swiss Chard 1 cup cooked 35.0 0.03 9.38 4.8 very good
Brussels Sprouts 1 cup raw 37.8 0.03 9.38 4.5 very good
Mustard Greens 1 cup cooked 21.0 0.03 9.38 8.0 very good
Broccoli 1 cup raw 30.9 0.03 9.38 5.5 very good
Kale 1 cup cooked 36.4 0.03 9.38 4.6 very good
Cauliflower 1 cup raw 26.8 0.02 6.25 4.2 very good
Green Beans 1 cup raw 31.0 0.02 6.25 3.6 very good
Garbanzo Beans 1 cup cooked 269.0 0.14 43.75 2.9 good
Barley 1 cup, cooked 270.0 0.12 37.50 2.5 good
Sesame Seeds 0.25 cup 206.3 0.12 37.50 3.3 good
Sunflower Seeds 0.25 cup 204.4 0.10 31.25 2.8 good
Cashews 0.25 cup 189.5 0.09 28.12 2.7 good
Peanuts 0.25 cup 206.9 0.09 28.12 2.4 good
Buckwheat 1 cup 154.6 0.08 25.00 2.9 good
Almonds 0.25 cup 206.0 0.07 21.88 1.9 good
Yogurt 1 cup 154.3 0.07 21.88 2.6 good
Millet 1 cup cooked 207.1 0.07 21.88 1.9 good
Quinoa 42.50 g 156.4 0.07 21.88 2.5 good
Potatoes 1 each baked 160.9 0.07 21.88 2.4 good
Rye 0.33 cup 188.5 0.06 18.75 1.8 good
Brown Rice 1 cup 216.4 0.06 18.75 1.6 good
Green Peas 1 cup raw 115.7 0.05 15.62 2.4 good
Sweet Potato 1 cup baked 102.6 0.05 15.62 2.7 good
Flax Seeds, ground 2 tbs 74.8 0.04 12.50 3.0 good
Winter Squash 1 cup baked 75.8 0.03 9.38 2.2 good
Beets 1 cup raw 58.5 0.03 9.38 2.9 good
Onions 1 cup raw 64.0 0.02 6.25 1.8 good
Basil 2 tsp 7.0 0.01 3.12 8.0 good
Apricot 1 each 16.8 0.01 3.12 3.3 good
Bell Peppers 1 cup raw 28.5 0.01 3.12 2.0 good
Romaine Lettuce 2 cups 16.0 0.01 3.12 3.5 good
Celery 1 cup 16.2 0.01 3.12 3.5 good
Oregano 2 tsp 9.5 0.01 3.12 5.9 good
Mustard Seeds 2 tsp 20.3 0.01 3.12 2.8 good
Cucumber 1 cup 15.6 0.01 3.12 3.6 good
Garlic 1 oz-wt 26.8 0.01 3.12 2.1 good
Plum 1 each 30.4 0.01 3.12 1.9 good
Eggplant 1 cup raw 19.7 0.01 3.12 2.9 good
Thyme 2 tsp 7.7 0.01 3.12 7.3 good
Summer Squash 1 cup raw 18.1 0.01 3.12 3.1 good
Cabbage 1 cup raw 17.5 0.01 3.12 3.2 good
Sea Vegetables 0.25 cup 8.6 0.01 3.12 6.5 good
Tomatoes 1 cup raw 32.4 0.01 3.12 1.7 good
World's Healthiest
Foods Rating
excellent DV>=75% OR
Density>=7.6 AND DV>=10%
very good DV>=50% OR
Density>=3.4 AND DV>=5%
good DV>=25% OR
Density>=1.5 AND DV>=2.5%

Public Health Recommendations

What are current public health recommendations for tryptophan?

In its most recent 2005 public health recommendations for amino acids (published as the Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients), National Academies Press, 2005), the National Academy of Sciences (NAS) established a general principle for tryptophan intake. The NAS recommended that all individuals 1 year of age or greater consume 7 milligrams of tryptophan for every 1 gram of food protein. Here is how that recommendation would look for each age and gender group, assuming RDA-level protein intake for each group:


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