FDA supplement warning letters: 2008 year in review

By Ivan Wasserman and Svetlana Walker

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FDA supplement warning letters: 2008 year in review
The US Food and Drug Administration (FDA) issued over 40 warning letters to supplement marketers last year. An analysis by FDA legal specialists Ivan Wasserman and Svetlana Walker reveals that the agency’s focus was on cancer claims made on internet web sites.

The oftentimes ‘fuzzy’ line between permissible and unlawful claims for dietary supplements makes it essential to stay apprised of FDA’s enforcement actions in order to successfully navigate the dietary supplement marketing waters without triggering regulatory scrutiny.

Warning Letters are one of the most common types of FDA enforcement actions against dietary supplements, and can provide insight into the types of claims and other issues that are at the top of FDA’s list for enforcement.

This article is an analysis of FDA Warning Letters issued to dietary supplement marketers in 2008.

What is a Warning Letter?

The agency sends Warning Letters to manufacturers or marketers to inform them of violations of FDA laws and regulations. FDA may observe violations during an inspection of manufacturing or other facilities. The agency can also review product labeling and, importantly, claims made on websites.

One area of focus for dietary supplements is the distinction between permissible ‘structure/function’ claims and unlawful ‘disease’ or ‘drug’ claims (i.e.,​ claims that the product will treat, cure, or prevent a disease.

FDA Warning Letters consist of a summary of facts or circumstances that the agency finds to be in violation of existing laws or regulations.

They describe the nature of the noncompliance and typically provide the recipient fifteen working days to notify the agency of the corrective actions the company intends to take to address the violations.

Unless the recipient is able to convince the agency that it was wrong about any of the alleged violations, failing to correct violations may lead to product seizures, injunctions, or other enforcement actions.

2008 letter lowdown

Our review identified 44 Warning Letters concerning dietary supplements issued by FDA in 2008. Some of the findings of our review are set out in the following chart, and discussed in more detail below.



‘Disease’ claims


Cancer claims


Heart disease/cardiovascular claims


Diabetes claims


Cold/flu claims


Other ‘disease’ claims


Claims made on websites


Claims made in metatags


Claims made on labels


Claims made in ‘third party literature’


Claims concerning ‘FDA approval’


Claims made in broadcast or print advertising


GMP violations


Tainted/contaminated products


Out of 44 warning letters issued to dietary supplement firms, 41 of them were issued as a result of FDA’s review of the firms’ websites. Only three letters were sent following facility inspections.

The amount of letters triggered by website reviews highlights the importance of diligence when it comes to creating website content. As a general rule, FDA can consider any statement or claim that appears on dietary supplement web pages to be a labeling claim for the product. This can include claims made in consumer testimonials and in third party literature excerpts that describe the health benefits of their dietary supplements.

Cancer claim clampdown

In terms of product categories, in 2008 FDA overwhelmingly targeted dietary supplements that made any type of cancer claim. Out of the 44 Warning Letters, 36 addressed cancer claims, making cancer by far the number one ‘disease’ targeted by FDA.

It should be noted that in many of the Warning Letters targeting cancer claims, FDA also identified other products and claims found on the same websites. Nevertheless, it is apparent that ‘cancer’ was a highly prioritized search term used in FDA’s online monitoring.


In addition, our review revealed that the agency is concerned with the use of metatags with ‘disease’ terms. Metatags are used by companies to cause search engines to identify their websites when certain search terms are used by consumers.

For example, because insomnia is a recognized ‘disease’, dietary supplements cannot make claims purporting to treat it. If a marketer uses the word ‘insomnia’as a metatag to drive consumers to a website that sells natural sleep aid or relaxation products, such as melatonin or valerian, FDA considers that to be additional evidence that the marketer is inappropriately promoting the supplement for disease treatment.

Almost half of the Warning Letters sent to dietary supplement marketers in 2008 identified the use of disease terms in metatags.

Third party literature

Finally, approximately 25 percent of the 2008 Warning Letters addressed third party literature violations, albeit as a secondary focus.

In the letters, FDA noted that the use of excerpts from scientific publications, or citations to scientific publications in the same context as the marketing of a dietary supplement, was problematic if the excerpt or citation involved disease treatment or prevention.

Accordingly, marketers of dietary supplements who cite to scientific studies or publications on their websites may want to review their existing third party literature policies in order to ensure that the placement and context of their scientific information does not violate FDA’s regulations.

Ivan Wasserman is a partner, and Svetlana Walkeris an associate at Manatt Phelps & Phillips in Washington, DC. They specialize in advertising and labeling issues for the food and dietary supplement sectors.

Related topics: Regulation, Product claims

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