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Providing perspectives on recent research into vitamins and nutritionals


More On Dietary Supplement Purity and Safety

By Julia Bird

Another report has just come out about the dietary supplement industry. The 50+ minute video explores some of the issues with how dietary supplements are produced and marketed. One of the main points in the video is that the current regulatory framework is based on what the chief of Nutrition Business Journal John Bradley recently called an “honor system”. The companies that manufacture or sell dietary supplements are ultimately responsible for the quality, safety and efficacy of their products. Only when serious health issues emerge can the FDA begin what they describe as a “lengthy scientific and legal steps” to have the products recalled.

For example, the FDA issued a warning letter about products containing a stimulant dimethylamylamine (DMAA) linked to 86 counts of serious injury and deaths in April 2013, but it wasn’t until November 2013 that the products were recalled and the FDA stated that the products would be destroyed. It took another two years until November 2015 for the FDA to charge a criminal case against the companies responsible for producing and selling the supplements. But this is not the end of the problem: after only a few seconds of searching on the internet today, I found out that it is still possible to purchase these products, and there was one website set up to let consumers know where to buy products with the same composition as the banned products, including ones that still contain DMAA.

At the same time, the FDA released the results of a year-long sweep of products on the market to identify those that were tainted with contaminants. While civil injunctions and criminal actions against 117 manufacturers resulted from this sweep, it is not clear how thorough the investigation was and it is not possible to say what percentage of dietary supplement manufacturers are producing unsafe or questionable products.

Other reports have come in that point to issues with the purity or identity of dietary supplements. For example, various reports from Baker, Coghlan, Newmaster, Saper and Stoeckle found that supplements containing botanical ingredients were of poor quality. Substitution of ingredients were common, and there were contaminants including heavy metals, as well as undeclared fillers used in the products. A report from LeBlanc on whether the amount of vitamin D in supplements matches what is on the label found that only half of vitamin D3 tablets bought in stores contained doses that matched the labels according to accepted standards for the industry. A related study by Andrews found similarly high variation in the vitamin D content of multivitamin and mineral supplements.  

Our blog from last week looked at how consumers can choose supplements that meet standards for quality, safety, and reliability of claims on the label: by looking to see whether the product has been tested by an independent lab. In the LeBlanc study, only one supplement from the 15 vitamin D supplements tested were within specifications between lots, and that was the one that had been verified by a third-party laboratory. The verification program ensures that the manufacturer is working according to industry standards, and the product itself has been randomly sampled from supermarket shelves and tested to make sure that it complies with its label.

On the other hand, a reasonably comprehensive test by the consumer protection organization in the US, Consumer Reports, found that almost all of the 21 multivitamins they tested at two independent laboratories met the label claims for all vitamins and minerals, and none contained heavy metal contaminants. Even though the quality of these supplements was high, few had been officially verified by an independent program.

It is also important to be wary of products with claims that seem too good to be true, particularly with weight loss, body building or sexual enhancement products. These seem more likely to be tainted, as we reported in November last year.

It seems that the current regulations for the dietary supplement industry place consumers at risk of the practices of unscrupulous or negligent dietary supplement producers. As a minimum, products should contain what they say that they contain, and should not be contaminated. It would be better if non-compliant manufacturers could be penalized more quickly than the current situation, including faster product recalls. Allowing the industry to police itself is not effective to guarantee the quality and safety of all supplements. Choose supplements that have been checked by an independent third party to make sure that they are safe.

Main citation:

FRONTLINE, The New York Times and the Canadian Broadcasting Corporation. Supplements and safety. January 19, 2016.

Supporting citations:

Andrews KW, Pehrsson PR, Betz JM. Variability in vitamin D content among products for multivitamin and mineral supplements. JAMA Intern Med. 2013 Oct 14;173(18):1752-3. doi: 10.1001/jamainternmed.2013.8759.

Baker DA, Stevenson DW, Little DP. DNA barcode identification of black cohosh herbal dietary supplements. J AOAC Int. 2012 Jul-Aug;95(4):1023-34.

Coghlan ML, Maker G, et al. Combined DNA, toxicological and heavy metal analyses provides an auditing toolkit to improve pharmacovigilance of traditional Chinese medicine (TCM). Sci Rep. 2015 Dec 10;5:17475. doi: 10.1038/srep17475.

Consumer Reports. Choosing the right multivitamin supplement for you. September 2010.

LeBlanc ES, Perrin N, Johnson JD Jr, Ballatore A, Hillier T. Over-the-counter and compounded vitamin D: is potency what we expect? JAMA Intern Med. 2013 Apr 8;173(7):585-6. doi: 10.1001/jamainternmed.2013.3812.

Newmaster SG, Grguric M, Shanmughanandhan D, Ramalingam S, Ragupathy S. DNA barcoding detects contamination and substitution in North American herbal products. BMC Med. 2013 Oct 11;11:222. doi: 10.1186/1741-7015-11-222.

Saper RB, Phillips RS, Sehgal A, Khouri N, Davis RB, Paquin J, Thuppil V, Kales SN. Lead, mercury, and arsenic in US- and Indian-manufactured Ayurvedic medicines sold via the Internet. JAMA. 2008 Aug 27;300(8):915-23. doi: 10.1001/jama.300.8.915.

Stoeckle MY, Gamble CC, Kirpekar R, Young G, Ahmed S, Little DP. Commercial teas highlight plant DNA barcode identification successes and obstacles. Sci Rep. 2011;1:42. doi: 10.1038/srep00042. Epub 2011 Jul 21.