St. John's Wort For Depression
By Anthony Almada, MS

New studies on St. John's wort (Hypericum perforatum) demonstrate why the herb continues to be popular in the media and among researchers. However, results from some recent studies suggest there are limits to the herb's antidepressant properties. Researchers confirm it may help with anxiety and memory disorders, but they raise cautions about its interaction with certain drugs.

A number of human studies have already indicated that St. John's wort is a well-tolerated and effective treatment for mild to moderate depression. However, researchers conducting a recent study sponsored by the National Institutes of Health (NIH) found St. John's wort no more effective for treatment of severe depression than a placebo or the antidepressant drug Zoloft. The study's researchers formulated their study in part out of concern that people with severe depression might self-medicate with the herb instead of seeking professional help. Researchers in a previous study published in the Journal of the American Medical Association also found St. John's wort ineffective compared to placebo in the treatment of severe depression. In light of these findings, those suffering from severe depression should first seek professional help.

It is also worth noting that not all St. John's wort extracts are alike, and only a few have been shown to be effective in treating human depression. The most thoroughly tested St. John's wort extracts for human use that are available in the United States are Kira, the extract used in the NIH study, and Perika.

Research continues into St. John's wort's many properties and potential uses. A large U.S. clinical trial of St. John's wort is further exploring its effectiveness in the management of mild to moderate depression, where its use appears at the moment to be most prudent.

(This is part one of a two-part series on St. John's wort. Next month, we outline the herb's effectiveness in treating anxiety and memory disorders. —Eds

Nutrition and exercise biochemist Anthony Almada, MS, has collaborated on more than 45 university-based studies, is cofounder of Experimental and Applied Sciences (EAS), and founder and chief scientific officer of IMAGINutrition.