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precursor to serotonin, melatonin, and niacin

  • amino acid essential for brain serotonin and melatonin production*
  • promotes relaxation, sleep, and good mood*
  • contains no preservatives, magnesium stearate, or other lubricants and diluents
  • made without flowing agents that can inhibit its bioavailability

Item Product Size Price
SA501 L-Tryptophan
Out of Stock
60 Vegetarian Capsules $37.10

Product Information

L-tryptophan is an amino acid essential to human metabolism because it is the metabolic precursor of serotonin (a neurotransmitter), melatonin (a neurohormone), and niacin (vitamin B3).* Other neurotransmitters and central nervous system chemicals, including dopamine, norepinephrine, and beta-endorphin, have been shown to increase following oral administration of tryptophan.* Because of its effects on serotonin and melatonin production in the brain, L-tryptophan supplementation can benefit mood and can also promote relaxation, a benefit for individuals attempting to get to sleep.*

Supplementing with L-tryptophan allows the body to use it where it is needed most - for protein synthesis, niacin formation, or as a serotonin/melatonin precursor.* For optimal L-tryptophan absorption and transport across the blood-brain barrier, it is recommended to take L-tryptophan with a dietary carbohydrate.*


Two Capsules Contain:
L-Tryptophan 1 g.
Other Ingredients: Hypromellose (derived from cellulose) capsule, Leucine, Microcrystalline Cellulose, Silicon Dioxide.

Suggested Use: Take 1-2 capsules two times daily or as recommended by a health-care practitioner.

Servings Per Container: 30
Please read the warnings for this product on the warnings tab.

Statements and Warnings

This product is contraindicated in an individual with a history of hypersensitivity to any of its ingredients.

This product does not contain wheat, gluten, corn, yeast, soy, egg, dairy products, or artificial colors, sweeteners, or flavors. This product also does not contain lactose, palmitic acid, or magnesium, calcium, or vegetable stearates.

If pregnant, consult your health-care practitioner before using this product.

There are no known adverse interactions or contraindications at publication date.

Health-Care Professional Resources

Clinical Depression: The Connections Between Fish Oil, Folate, Methylation, and Neurotransmitters Webinar

Alan L. Miller, ND, presents an intriguing look at the connections between depression, fatty acids, 5-methyltetrahydrofolate, and nutrient cofactors involved in neurotransmitter function. Dr. Miller explains how nutrient deficiencies, genetic enzyme polymorphisms, and lifestyle issues impact neurotransmitter function, and how repletion of these nutrients and enzyme cofactors support mood.

Novel Approaches to Stress: L-Tryptophan, 5-HTP, GABA, and Rhodiola Webinar

Certified nutritionist and author Tom Malterre, MS, CN, presents an exciting lecture on the biochemistry of the stress response, as well as nutrient and botanical approaches to effectively manage stress. With current events creating a pervasively stressed-out society, we all can benefit from this timely information.

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