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Office of Dietary Supplements Office of the Director National Institutes of Health Room 3B01, MSC 7517 6100 Executive Boulevard Bethesda, MD 20892-7517 E-mail: swansonc{at}od.nih.gov
About one-half of all Americans take =" BORDER="0"> 1 of the 29 000 dietary supplement products available from hundreds of manufacturers. Under the auspices of the American Dietetic Association, AS Fragakis, a San Francisco–based registered dietitian and nutrition counselor with a master’s degree in science, has written a book that primarily focuses on reviewing the scientific evidence and claims for 79 individual supplement ingredients. Her selections include 20 vitamins and minerals, popular herbs such as ginkgo and echinacea, and more esoteric specialty items such as bromelain and shark cartilage. The second edition of The Health Professional’s Guide to Popular Dietary Supplements updates and expands on the original volume published in 2000 with reviews of 10 additional supplements and the listing of hundreds of new references.
A brief introductory chapter lays out the organization of the book, which includes condensed monographs on the aforementioned supplement ingredients and 6 appendixes. Among the appendixes are an index of supplement ingredients sorted by their purported use as mentioned or discussed in the book, an overview of the federal government’s regulation of supplements with an emphasis on the 1994 Dietary Supplement Health and Education Act, and a discussion of ethical issues faced by health professionals when they advise on the use of supplements, particularly in the face of what Eisenberg (cited on page505) has called "inconclusive evidence about the safety and effectiveness of these therapies."
Of the book’s total pages between the introduction and appendixes, 90% are devoted to monographs on the supplement ingredients. Arranged alphabetically by ingredient name, these monographs average 6 pages each and are similarly structured: they cover food sources (when applicable), bioavailability and dosage information (when available), a review of relevant research, and safety issues. Each monograph is prefaced with a table listing the media and marketing claims for the ingredient, a summary evaluation of the scientific evidence for each of those claims, and possible or known drug-supplement interactions. More than 30 experts reviewed the monographs.
Fragakis indicated that the claims listed for each supplement ingredient were gathered from many sources, including "Web sites, product literature, magazine articles and advertisements, books and newsletters promoting supplement use, and health food stores." It is not clear that the claims evaluated by Fragakis are representative of the information used by consumers, but most of the claims listed in the book are related to disease prevention and treatment. Fragakis is appropriately cautious in drawing conclusions about whether each supplement ingredient does what its various proponents claim. Not surprisingly, she indicates that not enough research is available to make judgments or that the results of controlled studies in humans are equivocal.
Health professionals relatively unfamiliar with the world of dietary supplements—and even educated, health-conscious laypersons—will find Fragakis’s book to be a very useful introduction to the subject. More supplement-savvy persons may prefer more comprehensive, encyclopedic sources, such as the subscription-based, online Natural Medicines Comprehensive Database (www.naturaldatabase.com), which reviews hundreds of supplement ingredients and is frequently updated, and whose collection of monographs are also published in book form each year.