Why sometimes reading the label just isn’t enough
Think that it is alright to take Natural Health Product labels at face value? Think again. In fact, Natural Health Products are frequently mislabelled.
Our barcoding study, conducted at the Biodiversity Institute of Ontario, Guelph, and guided by Mehrdad Hajibabaei, revealed that 19% of Natural Health Products are substituted with different ingredients than those listed on the label. The resulting manuscript was published in Food Research International.
Why barcode Natural Health Products?
The Natural Health Products (NHPs) industry in North America has grown tremendously over the past few decades. Health Canada reports that 71% of Canadians regularly use NHPs, which include herbal medicines, homeopathic preparations, vitamin and mineral supplements and Chinese, Ayurvedic and Native North American medicine, and are generally used in complement with biomedical treatments.
Natural Health Products are often perceived to be safe due to their natural origin, however, adulterated, counterfeit and low quality products, which go undetected through mislabelling, pose serious safety threats to consumers. Although the mislabelling of Natural Health Products can be prevented through adequate regulatory mechanisms, enforcing regulations for product safety can become complicated because the content of the majority of Natural Health Products is difficult to ascertain, as they are sold as capsules, tablets, or dried parts.
In addition, unlike prescription drugs, NHPs are not regulated as closely. For example, in Canada, NHP regulations are stricter than regulations for food products, but less strict than the regulations for drugs in the country. Since 2004, there has been a backlog of product license applications to be processed. During some periods, this has led thousands of products to exist on the market without undergoing full screening for product safety. In the U.S. and the U.K., issues with the regulatory systems for Natural Health Products have also led to problems with their consistency and safety.
Enter DNA Barcoding
Curiosity about the actual content of Natural Health Products led our team of three undergraduate students at the University of Guelph to use DNA barcoding to authenticate 94 widely used plant and animal NHP Products, which included primarily shark fins and ginseng, but also encompassed black cohosh, green tea, Echinacea, and St. John’s Wort.
Guided by DNA barcoding researchers Mehrdad Hajibabai and Shadi Shokralla, I headed the study, funded by an Ontario Genomics Institute Summer Fellowship. Working with Stephanie Boilard and Shannon Eagle, who were also completing undergraduate research assistantships at the time, I found uncovering the true identity of products exciting.
Particularly interesting was the fieldwork required to obtain the products. All of the Natural Health Products sampled and sequenced were collected from field trips to pharmacies and informal markets in Toronto and New York. Acting as ordinary consumers, we shopped for natural products to aid in a wide variety of ailments, including the common cold, depression, stomach problems, and symptoms of menopause.
The most exciting part of the study was when the sequence results came in and we got to explore the health, environmental, economic and legal implications of the numerous substitutions and adulterations that we found. The results we obtained suggest that DNA barcoding is an excellent authentication tool for Natural Health Products and that consumers of Natural Health Products should be wary.
What is in your Natural Health Product?
Fully 81 per cent of Natural Health Products made from animals correctly matched their commercial label. The rest contained everything from cheaper alternatives to protected species.
Interestingly, half of the plant products labeled as Korean ginseng were really American ginseng. Whether these adulterations were completed as a result of taxonomic misidentification or were an attempt to make the consumer pay more for a fraudulent product, they have significant economic and health ramifications for consumers. This is because Korean ginseng is more expensive and is marketed for different medicinal benefits than American ginseng.
An equally interesting find is the sequence of one abalone product. Barcoding this product revealed that our specimen was another marine gastropod. This replacement may have been completed as a result of taxonomic misidentification, but could have also been completed knowingly. As world demand for abalone currently exceeds supply, abalone has become a luxury product, and commercially claiming this product is abalone would allow merchants to charge more for this product.
We found that barcoding could not only assist with the quality assurance for consumers, but with the identification of products that contain vulnerable species.
One of many factors affecting the decline of shark populations is the use of their fins in shark fin soup, a Chinese delicacy thought to have many health benefits. To prevent the decline of shark populations, which is exacerbated by finning, sharks have been protected in the territorial waters of several countries. However, for a non-expert, morphological keys are insufficient for identifying shark fins. As a result, it is difficult to track which species are being killed. Our study shows that DNA barcoding could be a viable part of this tracking process, providing a checkpoint for conservation organisations investigating species exploitation. Several of the shark species identified from the shark fins barcoded are listed on the International Union for the Conservation of Nature's "Red List" as in need of conservation.
The utility of DNA barcoding for food regulation has already caught the interest of regulatory agencies such as the U.S. Food and Drug Administration. Ultimately, our work demonstrates not only that DNA barcoding is a simple and efficient approach to identify the substitution and adulteration of Natural Health Products, but that it can aid in understanding and preventing the economic, legal, health and environmental impacts, of such substitutions.