Extracts from the berry of saw palmetto (Serenoa repens) are most commonly used for normalizing prostate function and relieving lower urinary tract symptoms (e.g., inability to void urine) related to benign prostatic hyperplasia.
According to the recent report from the American Botanical Council, sales of saw palmetto were $16.8 million in US mainstream multi-outlet channel in 2015 (number 14 on the top selling list), and a further $7.6 million in the natural retail channel (HerbalGram 111).
Reports of the addition of undeclared vegetable oils, including palm oil, canola oil, and coconut oil, to saw palmetto extracts for financial gain appeared in the early 2000s. Since these vegetable oils contain some of the same components as ripe saw palmetto berries, the detection of this type of adulteration is not always straightforward, states the bulletin.
It is even more difficult to determine the proper amount of saw palmetto in a finished product, since vegetable oils almost always are added (and appropriately declared on the label) as part of the semi-liquid formulation of the saw palmetto extract (e.g., in softgel capsules). Unscrupulous suppliers have taken advantage of these analytical challenges to pass vegetable oils as saw palmetto extracts entirely and/or to dilute saw palmetto extracts with the lower-cost vegetable oils.
The new bulletin, peer-reviewed by 10 experts, was co-authored by Scott Baggett, PhD, an analytical methods consultant for the natural products industry, and Stefan Gafner, PhD, ABC chief science officer and Botanical Adulterants Program technical director. It provides information on production, supply sources, and the market importance of saw palmetto and its extracts. It also provides information about known adulterants and analytical approaches to detect adulterants.
“The saw palmetto plant is known to grow and produce fruit (called ‘berries’ in the trade) only in the southeast United States, mainly Florida,” said Mark Blumenthal, founder and executive director of ABC and founder and director of the Botanical Adulterants Program.
“We have heard concerns for many years from ethical, responsible members of industry of the presence of ostensible saw palmetto extract containing low-cost vegetable oils as an adulterant. This creates unfair competition and reduces the potential health benefit to men who use saw palmetto to help manage urinary conditions.”
“There are high-quality saw palmetto extracts in the world market that are the subject of numerous published clinical trials demonstrating their safety and potential benefits in prostate health,” Blumenthal continued. “Consumers should be able to purchase these and other saw palmetto supplements with a sense that they contain appropriate amounts of true, authentic saw palmetto.”
A lack of reliable data
Dr Gafner added: “The sale of adulterated extracts is known to the reputable manufacturers of authentic saw palmetto extracts and to many responsible manufacturers of saw palmetto dietary supplements, but there is a lack of reliable data on the extent of the problem in the peer-reviewed scientific literature. Of particular concern are raw materials labeled as ‘saw palmetto extract’ that are imported from China, where saw palmetto is not known to grow.
“We hope that this Bulletin will help to raise awareness of this adulteration issue and ultimately increase the number of high-quality products in the market.”
The saw palmetto Bulletin is the eighth publication in the relatively new series of Botanical Adulterants Bulletins. Also available are Bulletins on adulteration of arnica (Arnica montana) flower, bilberry (Vaccinium myrtillus) fruit extract, black cohosh (Actaea racemosa) root and rhizome, goldenseal (Hydrastis canadensis) root and rhizome, grape (Vitis vinifera) seed extract, skullcap (Scutellaria lateriflora) herb, and St. John’s wort (Hypericum perforatum) herb.