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 them. The safety of supplements 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. (more…)
The FDA regulates in vitro diagnostic devices (IVDs) as medical devices. IVDs analyze human samples, such as blood, saliva, tissue and urine. However, in the past, the agency did not use its authority to regulate what are known as “laboratory-developed tests” (LDTs), tests developed and performed at a single laboratory, with all samples sent to that particular lab for testing. Instead, it focused on commercial tests kits, which are broadly marketed to laboratories or the public. These tests had to undergo the same pre-market approval process as other medical devices regulated by the FDA, including, in some cases, clinical studies demonstrating that the device is safe and effective for its intended use.
Historically, LDTs were developed by hospitals, researchers and academic medical centers for their own use. That is no longer true. In the past 15 years or so, there has been an explosion in the use of LDTs by commercial labs and biotechnology companies. The FDA now estimates that there are about 11,000 LDTs offered by 2,000 laboratories. One estimate is that the results of clinical lab tests (although not exclusively LDTs) influence 70% of health care decisions. (See the Congressional Research Service Report’s exhaustive analysis of FDA regulation of IVDs and inclusion of LDTs for more on the history and current use of LDTs.)
Do you have any idea whether the IVDs that have poked around in your blood or tissues are FDA-approved or unapproved LDTs? (Does your physician?) Do you know what evidence (if any) there is standing behind these tests? No? Me either. That’s because there is no requirement that anyone give you this information. (more…)
I was surprised to get this e-mail from a reader:
Surely, Dr. Hall, the public mania for nutritional supplements is baseless. All the alleged nutrients in supplements are contained in the food we eat. And what governmental agency has oversight responsibility regarding the production of these so-call nutritional supplements? Even if one believes that such pills have value, how can the consumer be assured that the product actually contains what the label signifies? I have yet to find a comment on this subject on your otherwise informative website.
My co-bloggers and I have addressed these issues repeatedly. Peter Lipson covered DSHEA (The Diet Supplement Health and Education Act) nicely. It’s all been said before, but perhaps it needs to be said again; and maybe by writing this post I can make it easier for new readers to find the information.