In the News - Press Coverage     Testimonials     Press Releases

60% of St. John's Wort Supplements Fail Tests of Quality

— Many Found to Be Low in Key Compound —
White Plains, New York, September 26, 2016 — St. John's wort extracts can be as effective as standard antidepressant drugs for treating mild to moderate major depression, with significantly fewer side effects. However, recent tests revealed that six of ten St. John's wort supplements contain much lower levels of key plant compounds than expected. These compounds, hypericins and hyperforin, are associated with the herb's effectiveness. In a suggested daily serving, found amounts of hypericins and hyperforin ranged across products by more than 2,000% and 20,000%, respectively.

"The wide variation across products means that some St. John's wort supplements may be helpful for depression, while others may not contain enough of the herb to have a meaningful effect," said President Tod Cooperman, M.D. The high failure rate may be attributable to adulteration of St. John's wort extracts with dyes which resemble St. John's wort when tested using outdated analytical methods. tested products using a method which identifies the hypericin molecule and is not "tricked" by dyes. The FDA does not specify which methods manufacturers must use to verify the quality of ingredients and supplements. Supplements were also tested by for potential contamination with the heavy metals arsenic, cadmium and lead and pills were checked to be sure they would break apart properly to release their ingredients. was able to identify four St. John's wort supplements which passed all of its quality tests and it identified a "top pick" among them.'s St. John's Wort Supplements Review is now available online at and covers the following 10 products: Gaia Herbs St. John's Wort Flower Buds & Tops, Nature's Way Perika St. John's Wort, NOW St. John's Wort, Planetary Herbals Full Spectrum St. John's Wort, Shaklee MoodLift Complex, Standard Process MediHerb St. John's Wort, Swanson St. John's Wort, Vitacost St. John's Wort Extract, Vitamin Shoppe St. John's Wort Extract and Whole Foods St. John's Wort.

The report summarizes the clinical evidence regarding the use of St. John's wort, including differences between forms (extracts and herb powders), dosage, what to look for on labels, possible side-effects, and potential drug interactions.

Founded in 1999, is a leading provider of consumer information and independent evaluations of products that affect health and nutrition. Membership to is available online and provides immediate access to reviews of more than 1,000 products from over 400 brands. The company is privately held and based in Westchester, New York. It has no ownership from, or interest in, companies that manufacture, distribute, or sell consumer products.

— END —

back to top



Coronavirus Information Center
Coronavirus Information Center
Answers to Critical Questions About COVID-19.

Product Reviews

In addition to our product reviews our encyclopedia covers the following:

Herbs & Supplements


Drug Interactions

Alternative Therapies



Follow us on...
facebook twitter
Join |  Sign In
Join Us on Facebook! Join Us on Instagram! Join Us on Twitter! Join Us on YouTube! Join Us on YouTube!
Product Reviews
Brands Tested
Health Conditions
CL Answers
Clinical Updates
Recalls & Warnings
Recommended Intakes
Where to Buy Products
Testing Program
How Products Were Tested
Quality Certification Program
Join CL Today
Join Free Newsletter
Group Subscriptions
Gift Membership
About Us
The CL Seal
CL Survey
Privacy Policy
Contact Us/Help

©2020, LLC. All rights reserved. A single copy of a report may be printed for personal use by the subscriber. It is otherwise unlawful to print, download, store or distribute content from this site without permission. name and flask logo are both registered trademarks of, LLC. This site is intended for informational purposes only and not to provide medical advice.