About Dietary Food Supplements

Many of the scientific and regulatory challenges that exist in research on the safety, quality, and efficacy of dietary supplements are common to all countries as the marketplace for them becomes increasingly global. This summarizes some of the challenges in supplement science and provides a case study of research at the Office of Dietary Supplements at the National Institutes of Health, USA, along with some resources it has developed that are available to all scientists.
 
The fundamental challenge in any discussion about the regulation of dietary supplements is that there is no global consensus on how the category of products known variously as dietary supplements, natural health products (NHPs), complementary medicines, or food supplements in different countries is defined. For example, a product considered to be a dietary supplement and regulated as a food in the USA, in another jurisdiction may be considered a food supplement or a therapeutic good (complementary medicine) or a therapeutic good (a prescription medicine) or potentially even a controlled substance.
 
The situation is even more complicated when countries like China or India that have an existing regulatory framework for traditional medicine or phytomedicine that includes crude botanicals are considered. To add further to the confusion, many regulatory frameworks are changing.
 
Another challenge is that while all regulatory scientists want to protect consumers from harm, ensure that consumers have the ability to make informed choices about the products they use, and do the right thing, the scientific challenges and regulatory systems that have arisen to deal with them vary greatly from country to country.
 
A final challenge is that “dietary supplement” health products are often very emotive and polarizing topics, evoking a diverse range of opinions and viewpoints. While some observers may contend that these products should be considered in a similar fashion to conventional drugs and foods, others believe that a more tailored approach is necessary since there is often a traditional or historical evidence base and products often contain multiple ingredients.
 
Increasingly, this situation has become even more complex because of the lucrative nature of the global dietary supplement sector, increased involvement of a growing industry sector producing them, and the introduction of many new and innovative products onto the market. A detailed discussion of the politics of the subject is outside the scope of this paper. However, it must be recognized that politics may play both a positive and negative role in shaping both regulatory frameworks and research agendas. Irrespective of the reader’s point of view, this context is important in any discussion of dietary supplement products.
 
The global market for food supplements is around 120 billion dollars with annual growth figures in recent years of around 6%. The main markets are those of Asia and North America followed by the European market. In Spain, the market for dietary products is around 1 billion euros, of which the sale of food supplements is around 350 million euros with more than 600 companies registered in this sector who market their products mainly in pharmacies, health stores, herbalists, supermarkets, and large retailers.