The findings were presented at an event branded as The Liver Meeting held by the American Association for the Research of Liver Diseases in Washington, DC. The research, presented by Dr Victor Navarro, MD of the Einstein Medical Center in Philadelphia and director of the National Drug Induced Liver Injury Network, reports findings from dietary supplements collected from cases of liver injury reported through the network. The research uses Navarro’s catch all term of ‘Herbal and Dietary Supplements’ as a grouping for dietary supplements and other similar products that are obtained when clinicians ask patients what they’ve been ingesting.
Majority of collected products were mislabeled
Between 2003 and March 2016, DILIN collected 341 herbal and dietary supplement products from 1,268 patients enrolled in DILIN. The National Center for Natural Products Research at the University of Mississippi conducted a chemical analysis on 229 of these products. The ingredients, as they were determined by the chemical analysis, where then compared to the ingredients listed on the 203 analyzed products that contained a label.
According to Navarro’s findings, which have yet to be peer reviewed for publication, only 90 of the 203 products surveyed were accurately labeled. Mislabeling — defined by the researchers as when the chemical analysis did not confirm the ingredients listed on the label — occurred in 80% of products used for body building and performance enhancement, and 72% of products used for weight loss.
“There is a growing concern that potentially mislabeled products may contain ingredients that can be highly toxic, and damaging, to the liver,” according to a press release from the DILIN.
“Since herbal and dietary supplements are not required by the FDA to be tested for safety or effectiveness, the DILIN has focused on various factors that could explain their potential for harm,” Dr Navarro said.
Improper to extrapolate findings to wider market
Experts in the field of dietary supplements said that the research had obvious limitations in that it represented a self-selected suite of products and shouldn’t be used to extrapolate to the wider dietary supplement market. Despite Dr Navarro’s repeated reference to the dangers presented by dietary supplements, Rick Kingston, PharmD, of the University of Minnesota School of Pharmacy, said the actual risk is very low. Kingston, who spoke with NutraIngredients-USA at the recent annual meeting of the Council for Responsible Nutrition, has broad experience in managing dietary supplement risk through his work with the consulting firm SafetyCall International, where he is president of regulatory and scientific affairs.
“Although mislabeling may have been prevalent amongst the samples in their population it cannot be assumed to be representative of the entire supplement market. And, considering the likely national denominator for prevalence of supplement use, the overall risk of experiencing liver injury for the average supplement user remains extremely low to remote. It will be helpful to sort through the labeled ingredient deviations to determine if the actual ingredients that were found in these products were potentially causal or otherwise associated with liver injury,” Kingston told NutraIngredients-USA.
Kingston said that in common with all sorts of adverse event reports, the associated factors with the individual liver injury events need to be considered when determining whether they represent an actual safety signal.
“Considering the class of dietary supplements products more commonly associated with reports of liver injury it will also be important to determine if other patient behaviors or lifestyles may also be contributing to adverse liver effects. In the end, we need to determine for those few patients that have been put at risk, which products and under what circumstances of use would they predictably produce liver injury,” he said.
More information needed to draw conclusions
Duffy MacKay, senior vice president of scientific and regulatory affairs for CRN, said more information is needed to fully assess the impact of Navarro’s findings. The sample collection spanned a long period of time and included many different types of products. What kind of sales channels are represented by these products? What’s the take away for the dietary supplement market as it stands today?
“Dietary supplement manufacturers are required to declare all ingredients on their product labels. Products that contain undeclared ingredients are illegal. Before drawing any conclusions, this new research should be peer-reviewed and confirmed, and the companies should be contacted for a response. Furthermore, in the name of transparency, the product names should be publicly disclosed. The manufacturing facilities in question should also be inspected by FDA, and if proven to be blatantly ignoring the laws that have been put in place to keep consumers safe, then swift enforcement action against the companies should follow,” MacKay said.