Do you take a vitamin or dietary supplement? Over half of all American adults do, making this a $30 billion dollar business. Many of us even take supplements in the absence of any clear medical or health need. I’m often told it’s a form of nutritional “insurance” or it’s being taken for some presumed beneficial effect – like Steven Novella outlined in yesterday’s post on antioxidants. We love the idea of a risk-free magic bullet that improves our health and wellness. Especially one that avoids what are presumed to be toxic, unnatural drugs. Supplements are marketed as safe, natural and effective, and there is no question that messaging has been effective.
I used to take supplements. For me it was multivitamins. But as I’ve taken a closer look at the evidence for supplementation, my personal behaviors changed. The primary reason is a lack of evidence. There is no evidence to suggest that vitamins offer any health benefits in the absence of deficiency. The balance of evidence suggests that routine multivitamins are unnecessary for most people. Vitamins should come from your food, not from supplements. More generally, looking at the broader category of supplements that range from probiotics to herbal remedies, there is little evidence to support most of them. With a few exceptions, the research done on dietary supplements is unconvincing and largely negative. If you don’t supplement, you don’t seem to be missing out on any tremendous health benefits.
Going beyond the lack of evidence, there’s an even more compelling need for consumers to be wary of supplements. The safety of these products is increasingly being called into question. Evidence has emerged demonstrating that quality standards for supplements sold in many countries are erratic and unpredictable. The root cause seems to be regulatory systems that prioritize manufacturer interests ahead of consumer protection. With supplements, products are effectively being tested for safety after they are marketed, and the consumer is the unwitting research subject.
Regardless of your personal position on supplements, I have yet to find someone that doesn’t want all supplements to be manufactured to high quality standards. What’s on the label should accurately describe what’s in the bottle, and there should be no exceptions to this. As a pharmacist, I can’t personally verify that each tablet in your prescription contains the active ingredient on the label. I am totally dependent on a supply chain that may stretch around the world, and tight regulatory standards that mandate quality testing of every batch of drugs. But none of these assurances are in place for dietary supplements. It’s only a regulator that can realistically verify and enforce production of drugs (or supplements) to strict quality standards. But with supplements, regulators are given different standard to apply.
Federal legislation enshrines your access to untested, dubious supplements
While the US Food and Drug Administration (FDA) is respected worldwide for pharmaceutical policy (few countries are as rigorous and as transparent), the same cannot be said for its regulation of supplements. Audits and recalls suggest that there is a small but persistent trend of poor manufacturing standards for American products. Adulteration, virtually unheard of with prescription drugs, seems to be a regular occurence with supplements – Vox recently published a long table of adulterated supplements. Poor quality should not be a surprise. It’s a consequence of legislation deliberately designed to weaken the FDA from regulating and providing oversight of supplements. The Dietary Supplement Health and Education Act of 1994 (DSHEA) was an amendment to the U.S. Federal Food, Drug and Cosmetic Act that established the American regulatory framework for dietary supplements. It effectively excludes manufacturers of these products from many of the requirements that are in place for prescription and over-the-counter drugs. Amazingly, it puts the requirement to demonstrate harm on the FDA, rather than the onus on the manufacturer to show a product is safe and effective. A weak regulatory framework, which doesn’t require pre-sale testing of product quality and finished product specifications, might be expected to result in a weaker commitment to quality. And that might be expected to result in erratic product quality, and possibly bad behavior from some manufacturers. And that’s exactly what we find when you look at supplement sales today. Happily, these effects are being reported to regulators, who are starting to act. Sadly, it’s been driven by a series of catastrophic harms suffered by consumers.
PBS Frontline describes the consequences of weak regulation
Last week the PBS television show Frontline focused on supplement safety. I strongly recommend listening or watching, as it paints a disturbing picture of how consumers continue to be harmed as a consequence of weak regulation and poor quality standards. A few highlights I picked up:
- The FDA does not review dietary supplements before they are sold in the market. There is no formal registration process for manufacturers. Consequently, the FDA doesn’t know how many companies produce supplements in the USA. (This is probably because the entire division dedicated to dietary supplements has just 25 people.)
- In 2013 Purity First vitamins were found to be laced with two anabolic steroids. Even after this was identified, it took the FDA six months to finally have the product removed from the market.
- Suspected harms and adverse events from supplements can be reported to the FDA. However, physicians interviewed reported difficulty in reporting problems, and in getting the FDA to take complaints seriously.
- The Children’s Hospital of Philadelphia, faced with patients bringing in supplements, took steps to validate their safety and quality. They decided to ask supplement manufacturers for certificates of analysis, which are documents which demonstrate that what’s on the label of a supplement is actually verified to be in the supplement, and that the supplement meets stated quality manufacturing standards. 90% never responded and of the 10% that did respond, most couldn’t demonstrate their products were manufactured to acceptable standards.
- Manufacturers fought the withdrawal of the stimulant supplement ephedra for over a decade. By the time it was finally withdrawn, over 160 deaths were linked to its consumption. The ban has effectively eliminated deaths and poisonings.
- Another supplement, OxyElite Pro caused an outbreak of hepatitis leading to liver failures, transplants, and deaths in some circumstances. The US Department of Justice recently announced it is pursuing civil and criminal charges against the manufacturer, USPLabs.
- Despite criticism from the industry about DNA barcoding, some manufacturers are starting to accept that this type of testing is essential if they’re going to address concerns about product quality. So they’re adopting these methods.
Frontline suggests you ask the following five questions before taking a supplement:
Has the product triggered any health warnings or sanctions? Searching the FDA’s website for a list of all recalls will identify if the product in question has been flagged. But given the few resources put into monitoring supplement safety issues, a lack of warnings is no assurance of quality or safety.
Has the product been tested by independent labs? This is currently very difficult to verify. Frontline mentions ConsumerLab.com and LabDoor as independent testing services with data available to the public. However even independent testing can be problematic, as you’ll see below.
Is the product too good to be true? While supplement makers are legally prohibited from making unfounded claims of efficacy, it’s not hard to find these claims on products. It’s important to note that there are no magic bullets out there. Outlandish claims (particularly common with products marketed for dieting) should not be believed.
Is there evidence that the supplement does what it promises? Look to reputable sources that summarize the evidence without bias. If there’s no good evidence supporting any efficacy claims, it’s a giant red flag that the product is probably bogus. Frontline suggests:
Thousands of studies have been conducted on the effect of various substances on the human body. The National Institutes of Health has summarized what is known about the most commonly consumed supplements — vitamins and minerals — in a series of fact sheets. These explain how each vitamin or mineral behaves in the body, and the scientific evidence behind its health impacts. The U.S. National Library of Medicine’s MedlinePlus has similar information about other drugs, herbs and supplements. For a deeper dive into the science behind a specific supplement, explore the Library of Medicine’s PubMed Dietary Supplement Subset. The database includes scientific literature on vitamin, mineral, phytochemical, ergogenic, botanical, traditional Chinese medicine, and herbal supplements in humans and animal models.
Resources are also available for certain groups: The Department of Defense offers information about the safety of specific supplements to service members. Older adults can find resources aimed at them created by the FDA, the Federal Trade Commission, National Institute on Aging, and NSF International.
Do I really need supplements? If so, am I taking the right amount? This is the key question, which is easier to answer after you’ve answered the questions above. There are some circumstances where specific supplementation is advisable. In other cases, it may not be essential. If you do need it, understand what the evidence says about the dosing, and ensure you’re taking a safe amount.
CBC Marketplace tested several supplements – and got it wrong
In a post on supplement safety and quality, I think it’s important to discuss how one group tested supplements – and how they got it wrong. Last week the Canadian consumer advocacy television show CBC Marketplace published a lengthy apology on its website. Its own analysis of supplements, which it had broadcast last fall, was faulty – and they were retracting the episode and apologizing:
Last fall, Marketplace commissioned lab testing for samples of fish oil, vitamin C and protein powder supplements to see if consumers are actually getting what they pay for. Based on those test results, Marketplace reported that Emergen-C and two protein powders: GNC Lean Shake 25 and Cytosport Muscle Milk failed to live up to label claims. However, subsequent re-testing of the samples has found that the lab results and analysis provided to Marketplace were incorrect, and that there is no evidence of problems with those products. The original lab tests were performed by an independent lab in Michigan, which is ISO-17025 accredited, registered with the U.S. Food and Drug Administration, and used by the supplement industry. The lab was recommended by Neil Thanedar, co-founder and CEO of LabDoor, a company that has products tested and makes those results public to help guide consumers about vitamins and supplements.
LabDoor’s investors and partners include Rock Health, a San Francisco-based venture fund that invests in health-care research, and the Mayo Clinic. Thanedar agreed to analyze the test results for Marketplace. The supplement companies strongly disputed those results. When Marketplace learned there might be a problem with one of the tests, CBC re-tested some of the products at other independent, accredited labs. None of them found problems with the samples.
So what happened here? Marketplace seemed to take all the right steps. It sought out what it thought was a reputable organization, Labdoor, to help with testing, which claimed the requisite expertise in evaluating product quality. The testing itself was done at a independent facility. Yet secondary testing refuted the original testing, and ultimately vindicated these three products – there were no problems, after all. What seems clear is that quality testing is not an easy matter. And Marketplace was testing fairly straightforward products. Imagine the complexity of testing herbal products – not only do you need to verify the raw material is present, but you must also verify the absence of adulterants like prescription drugs. In December I asked What’s in your Traditional Chinese Medicine after an analysis found dog, cat, snake, prescription drugs and heavy metals in products sold by retailers in Australia. What the CBC’s retraction says to me is that verifying supplement quality and standards may be even more difficult than we thought.
The supplement market is a massive uncontrolled, unmonitored clinical trial
While they may look like medicine, and be sold alongside medicines in the pharmacy, supplements are very different. With supplements, the testing may not begin until you start taking the product. A weak regulatory structure has resulted in a marketplace with thousands and thousands of products, but little assurance to consumers that these products are safe and effective. Consumers want safe products that work, but they are effectively research subjects in massive uncontrolled experiments. Manufacturers want to sell products, and will continue to push for the weakest, lightest regulation possible. The result will continue to be a marketplace where there is little assurance that any product label can be trusted. Until these quality and safety gaps are addressed with the appropriate incentives, penalties and regulations, it’s difficult to conceive how we can use supplements safely, and in a science-based manner.
Photo via flickr user Sarah Laval used under a CC licence.
Further resources
PBS Frontline: Supplements and Safety
Does your favorite supplement contain an illegal drug? Search the Vox database to find out.
Steven Novella: US Department of Justice goes after supplements
David Gorski: “Safe” dietary supplements can land you in the emergency room
Scott Gavura: Who takes dietary supplements? And why?
from Science-Based Medicine http://ift.tt/207v42k
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