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Can dietary supplement labels be trusted?

“New York Attorney General Targets Supplements”…four out of five of the products did not contain any of the herbs on their labels…The New York State attorney general’s office accused four major retailers on Monday of selling fraudulent and potentially dangerous herbal supplements and demanded that they remove the products from their shelves.”

Are you ready to toss out your supplements?

If you are like most people, you read headlines and skim articles. So you probably missed the “fine print” of this news story. Media outlets count on this. After all, bad news sells.

What if the headline read like this….

“DNA barcoding tests of herbal extracts produces misleading results…New York Attorney General over reacts.”

Would you still be convinced to never purchase another bottle of Echinacea again? Probably not. Yet the alternative headline is a lot closer to the truth.


Okay, you all know I am biased in favor of dietary supplements. Because of this, I tried to research this issue with an open mind. I will not tell you to continue taking herbs. That’s between you and your doctor. I will provide a more thorough explanation of the situation than any sensational headline. Don’t just take my word for it. Click on VIEW REFERENCES link at the conclusion and check out the facts for yourself.

So what’s all the fuss about?

An article was published in the New York Times8 on February 3rd, 2015 informing readers that the New York Attorney General had issued “cease and desist” letters to Target, Wal-Mart, Walgreens, and GNC after commissioning a study that used DNA bar code testing to verify the content of several popular herbs. He initiated the study in response to a 2013 study9.  These letters demanded each retailer stop selling “adulterated and/or misleading herbal dietary supplements.” Each letter specifically references the name and lot number of the tested products. You can view a copy of the letters at the New York Times.

The testing claims

  • Four out of five of the products did not contain any of the herbs on their labels
  • Major retailers are deliberately selling misleading herbal products.
  • At Walgreens a popular Ginseng contained powdered garlic and rice
  • At Wal-Mart, an unnamed brand of Ginkgo Biloba contained powdered radish, houseplants and wheat
  • At Target, undisclosed brands of St. John’s Wort, Ginkgo Biloba, and Valerian Root actually contained powdered rice, beans, peas and wild carrots
  • At GNC, pills contained unlisted ingredients and fillers such as powdered legumes
  • Just over 20% of all products tested actually contained what was on the label.8

Background info

Before I go into the problems with this study, you need a little background.

What is DNA bar code testing?

DNA bar code testing is the use of a shortened genetic sequence taken from the total genome of a known species in order to identify that species. It can be helpful when two plants appear similar. The use of DNA bar coding can help researchers confirm the identity of each plant. It makes sense to use this kind of testing when receiving raw materials to verify their authenticity11.

Some supplements have no DNA to test

The trouble arises when using this type of testing on standardized extracts. The American Botanical Council10 and the Natural Products Association both issued statements criticizing the testing method as inappropriate and yielding false results10, 4.

Here is why:

Herbal supplements are available in two forms: whole plant and standardized extracts.

Most people assume that when the bottle is labeled “Feverfew”, that the powdered substance in that capsule is actually ground up Feverfew. If you purchase “whole plant” supplements, then this is correct8.

However, if you purchase a “standardized extract”, then this is not true. You see, a standardized extract of Feverfew is created by a chemical process that extracts the assumed “active ingredient”, parthenolides, and discards the rest of the plant.  This extracted substance is mixed with inert fillers, ground into powder, and made into tablets or poured into capsules.

The headache experts tell us that we should look for a standardized extract of Feverfew at 0.2-0.4% parthenolides. This specific extract is the potency that has been clinically tested for effectiveness at migraine prevention.

This extraction process is the only way to ensure that each pill or each bottle has exactly the same amount of “active ingredient”. Extraction treats herbs as drugs by assuming that only part of the plant’s chemical make-up is “active” and the rest is “inert”. Because only one chemical is extracted, there is no plant DNA to be tested. Someone with a basic understanding of standardized extraction would understand this and not expect to find any plant DNA in a standardized extract10, 4.

We all know that oranges contain Vitamin C. Yet you will not find orange DNA in a Vitamin C supplement. Why would it be any different with herbal supplements? Herbs are plants, too.

Criticism from industry leaders

Both the NPA4 and the American Botanical Council10 submitted responses to this announcement, encouraging the AG to release the full report for public evaluation. Both organizations suggest that the testing method chosen may have been inappropriate for the supplements tested10, 4. A variety of experts in botany, herbalism, and chemistry have also criticized the AG’s office for its choice of testing method. Even harsher criticism accuses the AG’s office of using this study as a “publicity stunt” orchestrated to promote the new DNA bar code testing.

Be informed.

The brand names of the products tested have not been released. It is also not known if any of these products have GMP (good manufacturing practices)7 or TruLabel certification. Industry leaders acknowledge that contamination and misleading labeling does exist. They urge the FDA to increase its oversight and enforcement of existing laws in order to crack down on unscrupulous companies.

Look for GMP7  and/or TruLabel seals on dietary supplements in order to verify that the label actually reflects what is in the bottle. These certifications were designed to enhance consumer confidence by requiring supplement companies to adhere to independent testing and verification of all products. At this time, such oversight is voluntary. There are many reputable companies who voluntarily submit to examination of their manufacturing processes and the accuracy of labeling. You can find a list of GMP-certified companies6 at the NPA’s website. Look for these brands when shopping for dietary supplements.

Another way to verify the content and quality of your dietary supplements is to subscribe to ConsumerLab5. This is an independent quality assurance organization. They randomly test all kinds of dietary supplements and publish their results. Members receive a list of each product tested and whether they passed or failed. To sign up, go to

Be proactive

The risk of adverse events from dietary supplements is relatively low compared to those from prescription medications or even food10. However, as a part of the Dietary Supplement and Health Education Act of 1994 (DSHEA) 2, the FDA set up a protocol for reporting adverse events resulting from the use of dietary supplements. In the unfortunate event that you have a bad reaction to any dietary supplement, please report it to the FDA by visiting the Adverse Event Reporting online1.

The lesson

Whether dietary supplements, the latest migraine treatment, or any other consumer product, don’t just read and believe the headlines. Take your time. Research all the relevant data. If you need clarification, ask an expert. Whatever you do, don’t panic. Make your own choice based on the information available to you. Every headline has an agenda (including this one!). That motive may or may not be supported by the facts.

This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

  1. Dietary Supplements – Adverse Event Reporting, U.S. Food and Drug Administration, retrieved 2/3/2015 at
  2. Dietary Supplements, U.S. Food and Drug Administration, retrieved 2/3/2015,
  3. Esch, Mary, (2/3/2015). Study: many herbal supplements are not what the label says, ABC News, retrieved 2/3/2015 at
  4. Fabricant, Daniel Ph.D., (2/3/2015). NPA CEO responds to New York attorney general request to stop herbal supplement sales, Natural Products Association, retrieved 2/1/3/2051 at
  5. Major retailers accused of selling adulterated herbal supplements, ConsumerLab, retrieved 2/3/2015 at"
  6. NPA Certified Companies, Natural Products Association, retrieved 2/3/2015 at
  7. NPA GMP Certification Program, Natural Products Association, retrieved 2/3/2015 at
  8. O’Connor, Anahad, (2/3/2015). New York attorney general targets supplement a major retailers, The New York Times, retrieved 2/3/2015 at"
  9. O’Connor, Anahad, (11/3/2013). Herbal supplements are often not what they seem, The New York Times, retrieved 2/3/2015 at
  10. Vaughan, Karen, (11/5/2013). Are herbal supplements safe? Natural Health by Karen, retrieved 2/3/2015 at
  11. What is DNA Barcoding? Barcode of Life, retrieved 2/3/2015 at


  • arden
    5 years ago

    This is all very interesting and informative but as far as the AG recent testing goes we do not know whether they tested standardized extracts or whole plants. Without this information the DNA bar coding test can not be evaluated one way or another.

  • Luna
    5 years ago

    I am glad that you posted this information. My neighbor told me about the media article and I had the good information from here to give her truth about DNA testing.

  • Sandy
    5 years ago

    thank you Tammy. I have learned to read the whole article because writers often have a headline that the article is not about at all. I also read all the ingredients/labels and research especially vitamins and supplements since i have chronic allergies and have an egg and wheat intolerance. wheat used to be a big filler. since gluten free is the big thing now, it is changing.

  • Tammy Rome author
    5 years ago

    Fillers and binders are often whole foods like what was detected. Rice, beans, etc. are common fillers and are disclosed on the label as “binders and fillers”. This is actually a good thing. Combining organic foods (those with DNA present) with inorganic chemicals (one chemical from a plant), makes the supplement more easily absorbed.

    It’s like when a doctor tells you to drink orange juice with iron supplements. Most iron supplements are inorganic chemicals that are difficult for the body to absorb. By combining ferrous sulfate (iron) with a whole food high in Vitamin C, it is now more easiy absorbed by the body than if the iron supplement is taken alone.

    Reputable companies will disclose exactly what they used for fillers. It’s like reading a food label that says, “natural flavors”. The active ingredient ends up being an inorganic chemcial, not an organic substance, so it has no DNA.

    If you take a look at reference #10, you will find a great description of this process and encouragment that supplements purchased from naturopaths are of higher quality and not subject to the levels of contamination found in less expensive brands.

    Most people do not consult a naturopath. They just read mainstream headlines and purchase their supplements from major retailers. Those least able to use herbals appropriately are at greater risk of purchasing contaminated products. The article that prompted this response claimed that products found in national retail chains are “supposed to be of the highest quality”. That assumption is simply not true. Any serious student of herbalism will tell you that the highest quality products are found in the offices of naturopaths, TCM practitioners, etc. or cultivated by Master Herbalists with decades of experience. No one is testing these products because they are already voluntarily being subjected to independent testing by responsible manufacturers who bottle the herbs in pharmaceutical-grade laboratories with impeccable reputations.

    Do check out the references. You will learn a lot from further study. Your naturopath can also direct you to the independent studies on the supplements he or she prescribes.

    I can see the FDA eventually requiring a change in labeling requirements that better explains the difference between “whole plant” and “standardized extract” herbals. To use the same Feverew example from the article, new products might be labeled “Feverfew, whole plant” versus “0.3% Parthenolides derived from Feverfew”. There is a difference and consumers deserve to know.

    Hope this helps!

  • LT
    5 years ago

    Great article and excellent fact finding, and information about barcoding practices.

    My question is – why then did the barcoding system find things like carrots, beans and peas in supplements that otherwise should not have contained them? Were those the fillers and the barcoding did not pick up the active ingredient? Did the barcoding system confuse the active ingredient with another plant?

    I take a lot of supplements under the direction of a naturopath (reputable brands like AOR and Thorne Research), so this is very interesting to me.

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