What’s in your supplement?

In this 2010 report, Paul Solman gets the inside story on herbal supplements.

That ginkgo biloba you’ve been taking to improve your memory? Chances are it hasn’t helped. That’s because all you’ve ingested is some powdered radish, wheat and houseplants. Money well spent?

For the first time, law enforcement is going after major retailers and drug store chains that are selling herbal supplements that aren’t all they’re advertised to be. New York Attorney General Eric Schneiderman sent cease-and-desist letters to Target, Wal-mart, GNC and Walgreens Tuesday asking them to explain how they verify the ingredients in popular herbal supplements, which are exempt from Food and Drug Administration approval.

“Mislabeling, contamination and false advertising are illegal,” Schneiderman said in the letters, first reported by the New York Times. “They also pose unacceptable risks to New York families — especially those with allergies to hidden ingredients,” he continued.

Americans spend an estimated $5 billion a year on unproven pills and powders. Research the New York Times first reported on in 2013 is credited with leading to the New York Attorney General’s investigation.

Scientists have been using genetic testing to develop DNA bar codes for many different types of medicinal herbs. Testing 44 different supplements from popular brands in the U.S. and Canada against these genetic bar codes, researchers at the University of Guelph found that one-third contained no trace of the supplements advertised on the bottles.

And many of the unlisted fillers mixed with or substituted for the advertised supplements have their own potential side effects. For example, gingko biloba supplements also contained black walnut, which could be deadly for people with nut allergies. Economics correspondent Paul Solman examined the same issue in 2010. Watch his report above to see how scientists isolate single genes to generate bar codes and find out what kind of herbal “hamburger helper” is floating in your tea.

Editor’s Note: This story was first published in November 2013 and has been updated. The 2010 video mistakenly referred to the GATC building blocks of DNA as amino acids, when they are actually nucleotides.

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