American Journal of Epidemiology                                                                                          Vol. 154, No. 12
                             Copyright  © 2001 by the Johns Hopkins Bloomberg School of Public Health                                                 Printed in U.S.A.
                             All rights reserved
             Book Reviews Book Reviews
             BOOK REVIEWS
             From the Editor
                This issue of the Journal concludes Volume 154, in which                     tered and that they think might be of interest to the Journal’s
             a new format for the Book Reviews section was initiated.                        readership.
             Each issue of the Journal now contains a review of a book                          When suggesting books for review, be sure to provide
             relevant to the field and a brief editorial note. The editorial                 complete publication documentation (name of the publisher,
             note is not necessarily related to the particular book being                    ISBN number, etc.). Comments and suggestions may be sent                       Downloaded from https://academic.oup.com/aje/article/154/12/1160/64429 by guest on 09 January 2023
             reviewed, but it is, of course, also intended to have epi-                      to the Journal office in Baltimore or directly to the Book
             demiologic relevance.                                                           Reviews Editor by e-mail: ajebookreviews@yahoo.com. We
                We now solicit our readers’ reactions to the new format                      look forward to your feedback.
             and their suggestions for further improvements. Readers are
             invited to suggest books for review that they have encoun-                                                                  Warren Winkelstein, Jr.
                     Eat, Drink, and Be Healthy: The Harvard Medical School Guide to Healthy Eating
                                                                         By Walter C. Willett
                ISBN 0-684-863375, Simon and Schuster, New York, New York (Telephone: 800-223-2336, Fax: 800-943-9831, World
                                           Wide Web: www.simonandschuster.com), 2001, 304 pp., Hardcover $25.00
                “Eat, Drink, and Be Healthy”: Is this just another book                      on published data from major investigations such as the
             with a catchy title telling us what to eat? The public is inun-                 Nurses’Health Study, the Physicians’Health Study, and the
             dated with these tomes promising us the “truth” about nutri-                    Health Professionals Follow-up Study. Armed with this
             tion and health. At best, the vast majority of these works are                  information, he takes on an icon of the establishment: the
             naive and proselytizing; at worst, they are disingenuous and                    US Department of Agriculture (USDA) Food Guide
             deceitful manipulations of science. So, what does Dr. Walter                    Pyramid (2). The Pyramid, according to Willett, represents
             Willett’s book have in common with these other works?                           the views of an amalgam of special interests molded
             Absolutely nothing. Here is one of the few books on nutri-                      together in the cauldron of the Department of Agriculture.
             tion and health written for the lay public that is based on a                   Why the USDA, an agency responsible for promoting
             careful and thoughtful analysis of (of all things) science!                     American agriculture, has ultimate authority over what
                Nothing is particularly new or unusual about this book—                      many consider the single most important tool for improving
             and that is its strength. Willett says at the beginning of chap-                the nation’s health is not addressed; but setting politics
             ter 3, “My aim in this book is to offer straightforward, no-                    aside, Willett minces no words about the problems with the
             nonsense advice on nutrition based on the best information                      current Pyramid: “At best, the USDAPyramid offers wishy-
             available” (1, p. 35). The book is approximately 300 pages                      washy, scientifically unfounded advice on an absolutely
             in length and divided into 12 chapters, each clearly written                    vital topic—what to eat. At worst, the misinformation con-
             and respectful of the reader’s intelligence but careful to                      tributes to overweight, poor health, and unnecessary early
             define scientific jargon. The introduction and the first two                    deaths. In either case, it stands as a missed opportunity to
             chapters explain the purpose of the book and give the reader                    improve the health of millions of people” (1, p. 16).
             the groundwork necessary to understand Willett’s argu-                             From the ashes of the USDA Pyramid arises the phoenix
             ments. Chapters 3–11 specifically address the elements of                       of Willett’s new pyramid. There are seven fundamental prin-
             his arguments. The 12th chapter, nearly one third of the                        ciples: “watch your weight,” “eat fewer bad fats and more
             book, is devoted to recipes.                                                    good fats,” “eat fewer refined-grain carbohydrates and more
                In the book’s preface, Willett states that his intent is to                  whole-grain carbohydrates,” “choose healthier sources of
             “share with you what my colleagues and I have learned                           proteins,” “eat plenty of vegetables and fruits, but hold the
             about the long-term effects of diet on health.” By and large,                   potatoes,” “use alcohol in moderation,” and “take a multivi-
             he does just this. He educates the reader about how we know                     tamin for insurance.” There is nothing terribly radical here.
             what we know with a gentle diversion into methods of                               All in all, Willett’s arguments are thoughtful, logical, con-
             inquiry: randomized trials, cohort studies, case-control stud-                  cise, and supported by scientific evidence; but what does he
             ies, and metabolic studies. Most of his conclusions are based                   have against potatoes? One medium-sized baked potato with
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                                                                                                                      Book Reviews 1161
           skin has just 200 calories and is virtually fat-free. Potatoes      get the better of him when he claims that “a healthy diet
           are a good source of fiber, iron, phosphorus, vitamin B6, and       teamed up with regular exercise and no smoking can elimi-
           niacin, and a fair source of vitamin C. They are an excellent       nate 80 percent of heart disease and 70 percent of some can-
           source of potassium; in fact, half of a large baked potato          cers” (1, p. 15).
           with skin contains more potassium than a 6-ounce (18-dl)               Willett himself warns us about taking it all too seriously
           glass of orange juice. Willett, usually the ever-critical scien-    by quoting Mark Twain: “Be careful about reading health
           tist, seems to have lost his edge on this one. His argument is      books. You may die of a misprint.” Given the caveats men-
           based on the “glycemic index” hypothesis (3). It has been           tioned above, one need not “be careful about reading” this
           known for a long time that some foods contain readily               book. It is not the long-awaited Holy Grail of human nutri-
           absorbable sugars that lead to a rapid rise and subsequent          tion, and it certainly does not claim to be. What it is, how-
           fall in serum insulin levels (high-glycemic-index foods). It        ever, is a thoughtful assessment based primarily on epi-
           is this sudden “stress” on the islet cells of the pancreas (or      demiologic studies. Furthermore, it provides, as Willett
           something else not yet understood) that may be a contribut-         claims, “a solid sense of state-of-the-art healthy eating          Downloaded from https://academic.oup.com/aje/article/154/12/1160/64429 by guest on 09 January 2023
           ing factor in the development of type 2 diabetes mellitus.          today.”
           Studies of skinless potatoes fed to subjects who have fasted           Subjecting the discipline of medicine to the rigors of sci-
           overnight (1, p. 93) do show a sudden rise in insulin levels        entific investigation (the catch-phrase today is “evidence-
           (i.e., the potatoes have a high glycemic index), but a person       based medicine”) has led us out of many centuries of dark-
           rarely sits down and eats just potatoes on an empty stomach.        ness. Walter Willett is to be congratulated for doing this with
           For the glycemic index of potatoes to be helpful, insulin lev-      nutritional science. Over the next decade, many more stud-
           els must be measured when the potatoes have been con-               ies on nutrition and health will bring forth fruit. We can only
           sumed along with a meal—something that has not been suf-            hope that Walter Willett will be around to communicate this
           ficiently studied.                                                  information to the public.
             There is an important omission in this book. Obesity,
           hypertension, and diabetes mellitus are epidemic in our soci-
           ety, but they are especially rampant in the lower socioeco-                                  REFERENCES
           nomic groups. There are a myriad of reasons for this, but            1. Willett WC. Eat, drink, and be healthy: the Harvard Medical
           diet is certainly an important one. From a public health per-           School guide to healthy eating. New York, NY: Simon and
           spective, improving the nutrition of this group of people               Schuster, 2001.
           would give us the greatest “bang for the buck.” It would             2. Food and Nutrition Information Center, National Agricultural
           have been nice to see more of Willett’s creative energy                 Library, US Department of Agriculture. The Food Guide
           focused on this aspect of the problem.                                  Pyramid. Beltsville, MD: US Department of Agriculture, 2000.
             A couple of other quibbles: Willett advocates taking a                (www.pueblo.gsa.gov/cic_text/food/food-pyramid/main.htm).
           multivitamin “for insurance.” Here he departs from recom-            3. Jenkins DJ, Wolever TM, Taylor RH, et al. Glycemic index of
                                                                                   foods: a physiological basis for carbohydrate exchange. Am J
           mendations based on research “gleaned from studies that                 Clin Nutr 1981;34:362–6.
           have tracked hundreds of thousands of people for over 20
           years” (to quote from the book’s jacket) and resorts to per-                                   John Swartzberg
           sonal opinion. (We cannot be too hard on him for this con-                                     Sheldon Margen
           clusion: Our own UC Berkeley Wellness Letter also advo-                                        School of Public Health
           cates a daily multivitamin, but only for older people.)                                        University of California, Berkeley
           Another: In Willett’s introductory chapter, hyperbole may                                      Berkeley, CA 94720
           Am J Epidemiol Vol.154, No.12, 2001