The Vegetarian Resource Group Blog

Amino Acid Supplement and Sleep Aid Tryptophan Usually Microbially Derived; May Be Sourced from Duck Feathers or Human Hair

Posted on April 04, 2011 by The VRG Blog Editor

by Jeanne Yacoubou
VRG Research Director

Tryptophan is an essential amino acid, meaning that humans must consume it in their diet. As an amino acid, it is a component of protein. Tryptophan is also a precursor for the neurotransmitter, serotonin, and the hormone, melatonin. This amino acid is readily obtained by common high-protein food sources such as soybeans, certain seeds, eggs, milk, and meat.

Tryptophan is believed by some to help as a sleep aid and is often sold as a dietary supplement for this purpose. There is also a form of tryptophan sold as Tryptan™, a prescription drug intended to aid the uptake of certain psychiatric drugs.

In 1989, tryptophan was banned for sale in most countries due to several reported incidents of death and serious health effects. Known as Eosinophilia-Myalgia Syndrome, EMS was linked to a contaminated batch of tryptophan. Currently, pharmaceutical grade tryptophan is believed to be safe.

Although most sources report that tryptophan is industrially produced by bacterial fermentation, a major food ingredient supplier in the United States told The VRG in March 2011 that its source of tryptophan is duck feathers or human hair.

Ajinomoto AminoScience is one company that produces a pharmaceutical grade tryptophan, known by the trade name TryptoPure™, through microbial fermentation using only non-animal materials. Several dietary supplement companies contacted by The VRG reported in March 2011 that their tryptophan is produced through microbial fermentation and many carry this brand.

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The contents of this website and our other publications, including Vegetarian Journal, are not intended to provide personal medical advice. Medical advice should be obtained from a qualified health professional. We often depend on product and ingredient information from company statements. It is impossible to be 100% sure about a statement, info can change, people have different views, and mistakes can be made. Please use your best judgment about whether a product is suitable for you. To be sure, do further research or confirmation on your own.

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