The China Study

by T. Colin Campbell and Thomas M. Campbell
417 pp. Paper, $ 24.95
BenBella Books, Dallas, TX, 2005
ISBN: 1-932100-38-5.

Reviewed by Wilfred Niels Arnold
University of Kansas Medical Center

warnold@kumc.edu

Any serious challenge to the "American Diet" is bound to elicit some academic, public, and food industry opposition, which will range from mild skepticism through agitated re-evaluation to bitter disdain. What makes this particular contribution exciting is that the authors anticipate resistant and hostile sources, sail on with escalating enthusiasm, and furnish a working hypothesis that is valuable. In fact, the surprising data are difficult to interpret in any other way. Apart from the practicality of the subject, I recommend The China Study for its interdisciplinary approach and the integration of science, economics, politics, and culture——themes for Leonardo readers.

The senior author is Professor Emeritus of Nutritional Biochemistry at Cornell University, Ithaca, New York. He has studied and written about food for more than forty years, during which his initial and favourable regard for an American diet rich in animal protein (an almost universal opinion at the time) changed dramatically to the lonely position of alerting us to associations among animal protein intake, certain cancers, and other diseases. One of the first pieces of experimental evidence along these lines came from the outcome of rats challenged with aflatoxin (of fungal origin) and then fed a constant calorie diet containing either 20% protein or 5% protein. [The protein was none other than casein, a major constituent of cow's milk.] Against all guesses at the time, the animals on 20% protein developed numerous cancerous foci in their livers whereas the 5% protein group were virtually free of lesions. These observations seemed to echo the higher incidence of liver cancer (from aflotoxin-contaminated peanut butter) in the children from more affluent families (higher animal protein diets) compared with poorer families, in the Philippines, during the 1960's and 70's.

The book's title hails from a 20-year research partnership among investigators at Cornell University, Oxford University, and the Chinese Academy of Preventive Medicine, to survey disease incidence and lifestyle factors in rural China and Taiwan. According to Campbell, one of the directors, "this project eventually produced [many] statistically significant associations between various dietary factors and disease." And "people who ate the most animal-based foods got the most chronic disease and people who ate the most plant-based foods were the healthiest and tended to avoid chronic disease."

Many of us will continue to find enthusiasm for the health benefits of low-calorie and low-fat diets, and for exercise. The Campbells do not deny this. The coincidence of higher fiber intake on the plant diet is also embraced and the avoidance of xenobiotics will continue to find common support. But the most contentious issue in the book under discussion will be the claimed superiority of an adequate (underline "adequate") amount of plant protein versus the deleterious effect of animal protein. A restriction in amount, or a limitation in the rate, of synthesis of new protein in the organism seems to provide some incidental advantage in avoiding or ameliorating disease! It flies in the face of a better distribution of essential amino acids in animal proteins (for example, casein) compared with most (but not all) plant proteins. It may also evoke conniptions in some primary and secondary food industries.

The arguments within The China Study are at a level matching the "informed" reader, although I believe that a graded and more advanced development could have been added in some sections to good effect. The quantitative data (always a concern for a general audience) is straightforward and will be readily comprehended. The index would have benefited from more entries and a deliberate redundancy in terms. The volume is well produced and reasonably priced.

The authors are not shy about jousting with past, present, and even anticipated critics. Faddish diets are deflated en passant by the Campbell sword. Readers without previous experience in nutritional research, or the nature of sponsorship by the National Institutes of Health and other agencies, or the manner in which Federal recommendations (including school lunch programs) come to pass, will be a tad alarmed by chapters 13 through 18——and it's about time! This book will have an impact.