Mechanisms of action: Claims and challenge

Dietary supplement promotion hinges on the presentation and acceptability of structure/function claims. This shorthand is a conflation of the types of legal claims that may be made for dietary supplements. The law allows for claims regarding:

The last allowable claim often gets lost in the shorthand. The description of what specifically a nutrient does and how it does it—provided scientific evidence exists—is an acceptable structure/function claim. This area is an untapped source of claims that could provide meaningful opportunity for promotion.

Developing these claims can be challenging but rewarding. In an extreme example, if insulin were an acceptable dietary ingredient, then dietary supplements providing insulin could describe how it works, and thus make the connection to its effects on blood sugar because this mechanism of action is documented and understood. Just to be clear, insulin is not an acceptable dietary ingredient, as FDA considers it a drug. Other substances, however, may provide opportunity within the available scientific information to identify and communicate the mechanisms of action to the public in a compliant manner. Research shows the sports nutrition benefits of certain nutrients, such as increased muscle mass, improved recovery, increased fat metabolism, etc. Each nutrient (e.g., an amino acid or botanical extract) requires documentation for does in the human body.

First, one must recognize that “documented mechanism of action” is not well defined. The compilation of reliable scientific evidence is the obvious standard. Many of the components offered in sports supplement products have documentation as to how they work. Such claims are allowable. provided that the documentation is properly performed, measured, affirmed, compiled and presented. The lack of a clear definition of the required documentation affords opportunity while meeting the mandate for good science.

Secondarily, the explanation of the mechanism of action is more likely to be well received by the sports nutrition consumers, who often have an elevated baseline knowledge of such products. The explanation must clearly show how the substance works. the mechanism of action and the beneficial results are different. The best example involves “testosterone boosters.” If the increase in testosterone is due to a blocking of the metabolism of testosterone as opposed to causing the body to increase production of testosterone, the presentation of the mechanism of action may or may not be beneficial to the promotion. The correct characterization may not neatly align with marketing materials and thus must be considered carefully when promoting this aspect.

The opportunities to craft claims regarding how a nutrient works in the human body have always been part of the post-Dietary Supplement Health and Education Act of 1994 (DSHEA) world. The lack of formal definition of the mechanism of action should not deter brands from employing such claims, provided the science is well defined, fully descriptive of how the nutrient performs and addresses contradictory information concerning the mechanism. Knowing the mechanism of action can determine an ingredient’s benefits and how the ingredient works within the body, but it is important to remember that some claims, regardless of the accuracy, are disallowed. Remember FDA must be notified of all such structure/function claims within 30 days of first entrance to market. While “documented” has no formal definition when it comes to the mechanism of action, a standard should be developed and applied for individual purposes. Careful, deliberate scientific and regulatory evaluation of the available data should be maintained to ensure that the standards for substantiation of these mechanisms are acceptable to all stakeholders.

Moreover, these claim substantiation dossiers, per product, are subject to regulatory review upon request. The resultant claims and their effective use rests on this substantiation requirement, pending the regulations, which are subject to change.

Thus, ensuring a company has good practices in place to reevaluate claims and respective substantiation files on a routine basis is always recommended, especially when a given formulation changes.

As chief operating officer, Jim Lassiter oversees all consulting operations at REJIMUS, formerly Ingredient Identity. He has more than four decades of experience in quality control (QC), and government and regulatory affairs throughout the pharmaceutical, dietary supplement and natural product industries.