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5-HTP (5-hydroxytryptophan)

Researched in December, 2006

5-hydroxytryptophan, or 5-HTP as it is commonly called, is a supplement many people have asked me about that advertisers say may help with weight loss. I have checked briefly to see what is published. Conclusion: It may cause serious illness and death! Even though it is commercially available.

Tryptophan is the amino acid in turkey that makes us sleepy. 5-HTP is actually the precursor to the neurotransmitter serotonin (hy! Dosage in one supplement is 500 mg per day.

The relevant article in AJCN is "Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan" published 1992. In this study of 20 obese people taking 900 mg/day, people lost significant weight. The report concluded "These findings  together with the good tolerance observed suggest that 5-HTP may be safely  used to treat obesity."

However, when I searched HTP and safety, I found this comment: " Last month, a WARNING ABOUT 5-HYDROXYTRYPTOPHAN was mailed to many members of the life extension/nutritional supplementation community. This Warning alleges that little, if any, benefit is to be gained through use of 5 -Hydroxytryptophan (5-HTP), and that anyone using it is actually risking death! " However, the source of that warning was not reported, and the .net site stating there was really no hazard ended with an advertisement for HTP supplements.

And here is the warning - a February, 2001 showing that 5'-HTP is likely to cause a horrible syndrome and death!

Background on L-tryptophan and 5-hydroxy L-tryptophan and the eosinophilia myalgia syndrome

FDA took action to limit the availability of dietary supplements containing the amino acid that is the biological precursor of L-5-hydroxytryptophan, that is, L-tryptophan, because of the association between dietary supplements containing L-tryptophan and the 1989 epidemic outbreak of eosinophilia-myalgia syndrome (EMS) in the United States. In the summer and fall of 1989, an epidemic outbreak of eosinophilia-myalgia syndrome (EMS) occurred in the United States. This illness is associated with the use of dietary supplements containing L-tryptophan. In all, more than 1500 cases of EMS, including at least 37 deaths, have been reported to the national Centers for Disease Control and Prevention (CDC), although the true incidence of the disorder is thought to be much higher. Some individuals suffering from L-tryptophan-related EMS have recovered, while other individuals' illnesses have persisted or worsened over time.