The U.S. dietary supplement industry, estimated to include over 100,000 products, operates with significantly less regulatory oversight than prescription drugs, according to industry insights. Federal regulators do not review supplements or their labels before they are marketed, and manufacturers are not required to prove their products' safety, efficacy, or even their stated ingredients.
Despite these regulatory gaps, some manufacturers employ marketing strategies that can mislead consumers into believing their products have undergone rigorous vetting. David Trosin, managing director of NSF's health sciences certification program, highlighted two common tactics: "FDA registered" and "independently tested."
The phrase "FDA registered" is often used, but Trosin explains that it merely signifies that a company has filed basic information with the FDA. "Congratulations, you can go online and fill out a form," he stated. This designation does not indicate that the FDA has reviewed, tested, or approved the supplement's safety, efficacy, or quality.
Similarly, claims such as "independently tested" or "third-party certified" are not regulated and can be used by any brand, regardless of whether any outside lab has actually tested the product. Trosin noted that these phrases can be easily fabricated, stating, "All that took was Photoshop, really. There’s no grit behind it to indicate that it means something."
While federal law requires manufacturers to use appropriate tests to ensure products meet standards, including checks for undeclared drugs and heavy metals, these safeguards can be circumvented. Some companies may use "dry labs"—organizations that produce testing reports without actually conducting tests—or manipulate results to achieve desired outcomes. This practice can allow products with hidden toxins, unapproved pharmaceutical ingredients, or dangerously high ingredient levels to enter the market. In some instances, supplements may contain little or none of the active ingredients listed on the label.
Other common marketing terms that may not offer the security they suggest include "natural," "organic," "pharmaceutical strength," and "GMP" (Good Manufacturing Practices). "Natural" and "organic" are not regulated claims, and "pharmaceutical strength" lacks an official standard. While GMP indicates a facility follows certain safety standards, it does not guarantee the purity, safety, or accuracy of every batch.
Reputable brands may voluntarily seek certifications from independent organizations like NSF International. This rigorous and optional process involves facility inspections and product testing to verify ingredient authenticity, absence of contaminants, and adherence to good manufacturing practices. Brands that undergo this process, such as Nutrafol, Thorne, BodyHealth, MegaFood, and Timeline Nutrition, typically display NSF certifications prominently on their packaging. Consumers can verify these certifications through NSF's online database.
Studies have indicated potential issues within the supplement market. One analysis of 121 dietary supplements found that 5% exceeded safe daily consumption limits for arsenic, and others contained excessive levels of lead, cadmium, and aluminum. Another study detected bacterial and fungal contamination in all 138 products examined. Furthermore, a review of FDA data revealed that a significant number of over-the-counter supplements contained unapproved drug ingredients, with some containing multiple unapproved substances.
The FDA does conduct facility inspections and monitors adverse event reports. When public health concerns arise, the agency has the authority to remove products from the market. Approximately 75% of U.S. adults take dietary supplements, with more than 1,000 new products entering the market annually.