5-HTP

Claims, Benefits: Treats or prevents insomnia, depression, and other problems; modifies mood.

Bottom Line: In 1989, thousands of people taking tryptophan developed a rare and incurable blood disease, leading the FDA to ban all sales of the pills. 5-HTP, a close relative of tryptophan, is being taken as a substitute for it. Its potential dangers outweigh any possible benefits.

Full Article, Wellness Letter, January 2005:

Playing with Brain Chemicals

For years people took tryptophan pills to treat insomnia and depression and to improve mood. This amino acid is converted in the brain into serotonin, an important neurotransmitter that affects mood and sleep, among other things. But in 1989 the Food and Drug Administration (FDA) banned all sales of tryptophan because of an outbreak of eosinophilic myalgia syndrome (EMS, a rare disorder that affects the skin, blood, muscles, and organs) among thousands of people taking the pills. At least 30 people died. The epidemic was traced to a bad batch of tryptophan from one Japanese manufacturer, which apparently introduced an impurity when it altered its manufacturing process.

A cousin steps in

Since then 5-HTP (5-hydroxytryptophan), a close relative, has replaced tryptophan in health-food stores and drugstores and on the Internet. The body makes 5-HTP from tryptophan; and like tryptophan, 5-HTP is converted to serotonin in the brain. The supplement is derived from the seeds of an African tree. For decades European doctors have used it to treat depression and several other disorders. Some small studies suggest that 5-HTP may be as effective as standard antidepressants, but most of these studies were not well designed. And other studies have not found a benefit. There’s some preliminary evidence that the supplement may play a role in weight loss and may help against mild insomnia. One problem: when some people take the supplement, their blood levels of 5-HTP do not rise, so there’s little chance of a benefit.

Just how safe is it?

Reported side effects include nausea, vomiting, and difficulty breathing. High doses of 5-HTP can cause agitation, fast heart rate, a boost in blood pressure—and in rare cases, coma and even death. Combining it with an antidepressant, any other drug that affects serotonin levels (such naratriptan or sumatriptan, used to treat headaches), or “herbal antidepressants” such as St. John’s wort can also cause such side effects. People who have heart disease, peptic ulcers, kidney disease, or clotting disorders should definitely not take this supplement.

Even though the manufacture of 5-HTP is very different from that of tryptophan, worries about contamination remain. Researchers from the Mayo Clinic have found an impurity known as “peak X” in commercial samples of 5-HTP; the FDA has also spotted impurities. Substances similar to “peak X” were found in the tryptophan involved in the 1989 outbreak of EMS. So far, however, there have been no confirmed cases of the illness from 5-HTP supplements.

Final thoughts: Some dietary supplements, notably 5-HTP, can influence brain chemicals. As the tryptophan story showed, even though they are marketed as “natural,” they can have serious adverse effects—just like traditional antidepressants. The potential dangers of 5-HTP outweigh any possible benefits.

UC Berkeley Wellness Letter, January 2005