Adulteration: When ingredients aren't what they claim to be
I review findings on elderberry, one of the top-selling dietary supplement ingredients.
The adulteration of botanical products, particularly dietary supplement ingredients, continues to pose challenges for the supplement industry. Last week, the American Botanical Council released a new bulletin addressing the issue of adulteration in European Elderberry extract. The bulletin shed light on the inclusion of low-cost and inferior ingredients such as anthocyanin-rich extracts and food dyes in elderberry products.
European elderberry (scientific name: Sambucus nigra in the Viburnaceae family), also known as elderberry or European black elder, is widely used as a remedy for relieving symptoms associated with upper respiratory infections like colds and flus. Its efficacy in treating common cold symptoms is supported by a number of clinical studies, and lab studies (in test tubes) have demonstrated antiviral properties against the flu virus.
The public demand for elderberry supplements as a solution for cold and flu symptoms has surged, particularly during the initial months of the COVID-19 pandemic. In 2021, elderberry supplements emerged as the top-selling herbal dietary supplement ingredient in mass market stores and ranked third among botanical ingredients in natural retail stores. The total sales in both channels amounted to an impressive $305 million, according to the American Botanical Council’s annual Herb Market Report.
Before we dive into the specific issues with adulteration of elderberry, let’s start with some basics on what adulteration can entail.
What is adulteration?
Adulteration of dietary supplement ingredients refers to the intentional or unintentional addition of impurities or inferior substances to the ingredients used in supplements. It compromises their quality, safety, and efficacy.
Some of the different types of adulteration include:
Substitution with an inferior species. This happens when a cheaper, but botanically related plant is used in place of a more costly species on the label. This can be a problem for either farmed or wild harvested plant ingredients. A good example of this is using inferior species as a substitute in herbal stimulant laxatives.
Cases of mistaken identity. This happens when a similar-looking plant is used instead of the target species. This is an issue mainly for wild plants. For example, in the Balkans, I have witnessed that many medicinal plants sold into the global market are collected by young children who do not usually have the training to distinguish species.
Substitution with manufactured substances. An example of this is when cheaper paraffin wax is used in place of bees wax.
Addition of objects to increase the weight of materials for sale. For example, when stones are mixed into the chopped-up plant material.
Substitution with cheaper natural substances. This is when botanicals are substituted with or the amount stretched by adding superficially similar products (based on color or some similar chemistry).
Addition of synthetic products. Examples of this include addition of pharmaceutical drugs (see my post on sexual stimulants in ‘herbal viagra’).
What’s happening with elderberry?
As one of the top-selling ingredients of the supplement industry, it’s easy to imagine how bad actors might be financially incentivized to dilute or stretch the actual elderberry extract with cheaper ingredients.
Where is elderberry grown or wild harvested?
The majority (95%) of elderberries consumed in the US are imported, primarily sourced from European farms (Austria, Italy, Czechia, Poland, and Hungary) or from the wild in the Balkans and central Europe (Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Czechia, Hungary, Kosovo, Montenegro, Poland, Romania, and Ukraine). I’ve conducted months of fieldwork in the Balkans (especially in Albania and Kosovo) over the past decade in effort to understand both how wild plants are locally used as medicine and to support the local economy through their sale. Plants like the European elder are an important component of this trade network.
What are the common elderberry adulterants?
According to the Adulteration of European Elder (Sambucus nigra) Berries and Berry Extracts Bulletin of the Botanical Adulterants Prevention Program, the main adulterants fall into number 5 (Substitution with cheaper natural substances - other unrelated plant products) and 6 (Addition of synthetic products - dyes) above.
The adulterated ingredients are generally extracts that are labeled to contain elder berry but are diluted or substituted with extracts from lower-cost anthocyanin-rich plants, most notably black rice. Additionally, rare occurrences of adulteration with purple carrot (Daucus carota, Apiaceae) extract, rutin-rich extracts, anthocyanin extracts from unknown sources, or undeclared food dyes (Brilliant Blue FCF and Amaranth) have been described.
The report goes on to reiterate that financially-motivated dilution is the main culprit:
The main adulteration issue is the dilution or substitution of elder berry extracts with low-cost extracts from other anthocyanin-rich plant parts, especially black rice. The origin of such adulteration is clearly intentional as the suppliers’ motivation is of a financial nature. Manufacturers may unknowingly procure adulterated extracts when basing their acceptance criteria on insufficient testing.
The good news? There are established laboratory methods available to test these materials for the presence of these adulterants. However, based on the loose regulations of the supplements market, companies are not technically required to undertake such testing when purchasing bulk materials for manufacturing their supplement products.
The Takeaway
Adulteration is a problem on many levels. In addition to inaccurate reporting of ingredients, such practices also defraud consumers and put them at potential health risk if the adulterants have any toxicity concerns.
Unfortunately, I don’t have a magic answer on how to fix this issue. As a consumer, you can look into the product testing practices of your favorite companies and write letters to your congressional representatives advocating for more oversight. Change takes time and loud voices to spur leaders into action.
Yours in health, Dr. Quave
Cassandra L. Quave, Ph.D. is a scientist, author, speaker, podcast host, wife, mother, explorer, and professor at Emory University School of Medicine. She teaches college courses and leads a group of research scientists studying medicinal plants to find new life-saving drugs from nature. She hosts the Foodie Pharmacology podcast and writes the Nature’s Pharmacy newsletter to share the science behind natural medicines. To support her effort, consider a paid or founding subscription, with founding members receiving an autographed 1st edition hardcover copy of her book, The Plant Hunter.