Critics of the dietary supplements industry have long warned that you don’t really know what you’re getting when you buy supplements. Over the years, there have been numerous reports of products containing much less, or much more, than what’s listed on the labels. Worse yet, supplements have been found to contain undisclosed prescription drugs, as well as contaminants such as lead and other heavy metals.
To address these concerns, the Food and Drug Administration (FDA) issued final rules in 2007 that required supplement makers to follow more extensive “good manufacturing practices” (GMPs) to ensure the identity, purity, strength and composition of their products. This is a good first step, but how much of a difference can GMPs really make?
Since the Dietary Supplement Health and Education Act of 1994 (DSHEA) went into effect, dietary supplements have been regulated under the category of food—and as such, they’ve been covered by GMPs that basically check for sanitary conditions and consistency in production. The newer GMPs, however, are specific for dietary supplements and impose higher standards on these products than food GMPs do. For example, companies are now supposed to test all raw materials, set expiration dates based on documented science, ensure that workers are appropriately trained and follow proper procedures, and keep more extensive records, subject to FDA inspection.
Where the GMPs fall short. But the final rules were watered down from the original proposals. Not surprisingly, manufacturers fought against measures that would increase costs. What’s more, the FDA, despite increased funding and a pledge to substantially increase inspections, still lacks the resources to fully monitor compliance, which is often done through inspection of paperwork, not facilities.
In particular, the provision to test finished products was weakened by various loopholes in the final rules. Notably, products for which there are no validated testing methods, such as herbs, are exempt from testing. And the FDA has been criticized for not setting lead or pesticide limits in supplements. In effect, manufacturers can still cut corners and make poor-quality products and get away with it, even if they meet GMPs.
What to keep in mind:
- GMPs don’t guarantee safety. Ingredients can still have side effects and unknown long-term effects, interact with drugs, and be dangerous if you have certain medical conditions.
- GMPs have nothing to do with whether a product works. Manufacturers of supplements are still not required to submit evidence of effectiveness to the FDA. Even if, say, the glucosamine or ginkgo pills contain what the label states, that does not mean they will relieve arthritis or improve memory, as claimed. And if there were a benefit, there’s no guarantee that the recommended dose is the “right” one (even “standardized” doses for herbs can vary widely).
- GMPs do not change how supplements are labeled. Unlike labels on drugs, those on dietary supplements still need not list any precautions, contraindications, or possible interactions.
- Many supplements still fail to meet quality standards when put through random testing by independent organizations. GMPs should improve matters somewhat, but it will take time.