In Europe, St John’s wort is recognized as an effective antidepressant, while here in North America it is still viewed with a critical eye. This may change, however, as studies continue to prove its worth. In 2001, two studies provided conclusive evidence that St John’s wort was effective for mild depression—and unlike medications, it did not cause unwanted side effects such as drowsiness or low libido.

In the first study, 72 patients were given either a placebo or 300 mg daily of St John’s wort for 42 days. Within the first week, researchers noticed improvements in the St John’s wort group. Upon completion, depression scores for the St John’s wort group dropped by 10 points while the others dropped by only 5.5 points.

In the second study, 2,166 participants with mild to moderate depression were monitored by over 400 health practitioners. Participants were given either 600 mg or 1,200 mg of St John’s wort daily. The final results showed more than 80% of patients from both groups went from “moderate to less than mild depression.” In both studies, St John’s wort was well-tolerated by 99% of participants.

Researchers believe St John’s wort works because its components—hypericin and hyperforin—help maintain higher serotonin levels in the brain. Serotonin is a neurotransmitter that promotes feelings of calm and happiness. It is also believed to affect dopamine and norepinephrine, two mood-altering neurotransmitters. Look for a St John’s wort supplement that is standardized to 0.3% hypericin. The common dose is 300 mg, three times a day. Consult a health practitioner if you are taking other prescription medications.

Sources: Leslie Beck’s Nutrition Encyc by L Beck, Prentice:2001; Fortschr Med Orig 2001 Nov 29;119(3-4):119-28; Pharmacopsychiatry 2001;34:96-103