Updated

About two-thirds of people taking herbal supplements to treat a health condition don't check scientific guidelines, say University of Iowa researchers.

"Physicians, pharmacists, and other health professionals should proactively educate consumers and advocate for public health policies that would disseminate evidence-based information regarding the appropriate use of herbs," says researcher Aditya Bardia, MD, in a University of Iowa news release.

Bardia and colleagues reviewed data from a 2002 national health survey of more than 30,000 U.S. adults.

In the survey, more than 3,300 adults said they had taken herbs to treat a specific health condition.

The researchers focused on 609 people who reported treating a specific health condition with any of the following 10 herbal supplements: echinacea, ginseng, garlic, St. John's Wort, soy, or kava kava.

Unlocking the Secrets of Herbal Supplements

Bardia's team checked to see if there was scientific evidence supporting the use of those herbal supplements for the participants' health conditions.

Overall, about 55 percent of the participants used herbal supplements backed by scientific evidence for their condition.

However, the percentage of participants using herbal supplements in accordance with scientific evidence ranged from 68 percent for echinacea to 3 percent for ginseng.

Apart from echinacea and ginseng, about one-third of the participants used herbal supplements based on scientific evidence, the study shows.

Part of the problem may be that many patients and doctors don't talk about herbal supplements. That should change, note Bardia and colleagues.

Their report appears in the May edition of the journal Mayo Clinic Proceedings.

Test Your Supplements Savvy

This article was reviewed by Louise Chang, MD.

SOURCES: Bardia, A. Mayo Clinic Proceedings