Is 5-HTP Contaminated?

Comment by Miryam Williamson author and patient educator
Sept. 5, 1998

On August 31, 1998, the Mayo Clinic issued a press release announcing that researchers had published a report saying they had found in samples of off-the-shelf bottles of 5-HTP the same contaminant that caused the amino acid L-tryptophan to be banned from sale in the U.S. in 1990. The press release formed the basis of articles in the Washington Post and New York Times.  An Associated Press version found its way into newspapers all over the world. This article used to have a link to the Mayo Clinic press release, but the clinic has removed that page so I can no longer send you there to read it. 

What follows is the letter I wrote to editors of the two newspapers, and some additional comment.

To the Times and Post I wrote:

It would be helpful to readers of such articles if the reporter would include  the source of funding for studies such as the one reported by the Mayo Clinic finding a contaminant in samples of [5-HTP].
5-HTP competes in the marketplace -- with increasing success -- with Prozac and other serotonin-enhancing drugs. If a pharmaceutical company funded the Mayo study, that would be highly significant information.

I find the report particularly suspect because L-tryptophan is manufactured by a fermentation process, which was the source of the contamination in 1989.  5-HTP is not manufactured by fermentation. I cannot imagine how the same contaminant got into the 5-HTP unless it was placed there, inadvertently or on purpose.

After I wrote that letter I obtained a copy of the "report" on which the press release was based.  Usually, people think of a scientists' report as having been accepted for publication after review by the writers' peers -- other scientists. This report is actually a letter to the editor of the magazine Nature Medicine (September 1998, page 983). No peer review was involved, therefore its accuracy is open to question.

The letter to the editor says a woman was made ill by a contaminant in 5-HTP in 1991, and that the contaminant they found this time was "between about 3% and 15%" of what was found at that time.  That raises a question: why did they wait seven years to write about it if they thought there was a danger? Why do they write now when the amount found is so much less than at that time? I suspect the reason is that 5-HTP is growing in popularity, cutting into sales of Prozac and other SSRIs.

There is no mention of having tested pharmaceutical grade 5-HTP, the kind you get from one of the compounding pharmacies listed on this web site.  Two conclusions are possible: Either they tested the pharmaceutical grade and found no contamination but chose not to mention that fact, or they chose not to test it at all.  In either case, one must wonder about the scientific impartiality of the investigators.

Is there a risk in taking 5-HTP?  Of course there is.  Nothing is without risk: walking down a flight of stairs, eating a hamburger, or driving a car involves some degree of risk.  So does taking vitamins, minerals, amino acids, herbs -- or prescription medicines.  In any given year, approximately 63,000 Americans die from taking prescription drugs as their doctors prescribed them.  That's about three times the number of people who die from intentional homicide.  If anything near that number of people died, or even became ill, from taking nutritional supplements, you can be sure the US government would ban them from the marketplace.

I think we are seeing the beginning of an organized attack on 5-HTP by the pharmaceutical companies whose profits are threatened by the success in treating insomnia and depression of a substance they can't control or make money from. I see this as the first step in an all-out attempt to get 5-HTP banned from over-the-counter sales, as L-tryptophan continues to be even though the cause of the 1989 deaths is clearly known to be a contaminated product sold by a single manufacturer -- who is, by the way, still doing business in the US.

I further suggest that you make up your own mind based on an analysis of risks and potential benefits.  If you think there is less risk in taking a psychoactive drug or sleeping pill, then that's what you should do. Just don't let pseudo science of this sort scare you into doing, or not doing, anything.

Copyright ©1998, Miryam Ehrlich Williamson - ALL RIGHTS RESERVED
Revised March 14, 2001


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