Dietary Supplements – “Buyer Beware”
When lecturing about sports supplements over the years, I have always included the warning, “Buyer Beware” for all who purchase or discuss over-the-counter supplements. Supplements, which are a multi-billion dollar industry, do not undergo the same strict safety and effectiveness evaluations as used with prescription drugs. In 1994, the Dietary Supplement Health an Education Act (DSHEA) was established but unfortunately with different regulations and lack of strict oversight as seen with prescription drugs. Unlike prescription drugs, dietary supplements are considered safe until proven unsafe. The lack of significant regulation and the large number of products are major challenges to assuring safety in the supplement world. As an example, in 1994 there were about 600 US supplement manufacturers with 4000 products. By 2000, there were more than 29,000 supplement products on the US market with few documented reference materials for these products and there are now over 85,000 supplement products on the US market. To add to this challenge of regulation and safety, there is no global consensus on how dietary supplements, natural health products and food supplements from other countries are even defined.
A recent study by Tucker et al in JAMA, illustrates the difficulties in regulation and potential harm of dietary supplements. The study was an analysis of the US Food and Drug Administration warnings from 2007 to 2016, which showed that unapproved pharmaceutical ingredients were identified in almost 800 dietary supplements. The most common adulterants were sildenafil for libido products, sibutramine in weight loss supplements and synthetic steroids or steroid-like ingredients found in muscle building supplements. Twenty percent of the products identified contained more than one unapproved ingredient.
Over half of all adults in the United States report taking dietary supplements. Those adults and medical providers should be aware of the possible contamination risk and lack of quality seen in the supplement world. As medical providers, it is important to educate ourselves and our patients on this topic. Remember, “Buyer Beware”!
Dwyer, JT, et al. Dietary Supplements: Regulatory Challenges and Research Resources. Nutrients, 2018.
Tucker J, et al. Unapproved Pharmaceutical Ingredients Included in Dietary Supplements Associated With US Food and Drug Administration Warnings, JAMA Network Open, 2018.