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Evolutionary Aspects of Nutrition and Health:
Diet, Exercise, Genetics and Chronic Disease
Evolutionary Aspects of Nutrition and Health: Diet, Exercise, Genetics and Chronic Disease, edited by A.P. Simopoulos. World Review of Nutrition and Dietetics, Vol. 84. Basel, Germany: Karger, 1999. 145 pp. $175.00 (hardcover).
This volume of five edited papers is slim but substantive. The main theme of the volume is that humans are currently nutritionally out of synch with their genetic make-up, which evolved over hundreds of thousands of years prior to the Neolithic and the advent of the Agricultural Revolution. This type of evolutionary explanation for the proliferation of chronic diseases in the modern age was first introduced by Neel (1962) with the "thrifty gene" hypothesis and was later elaborated on by Eaton and Konner (1988) with the "Paleolithic prescription."
In fact, the first paper in the volume is by J.V. Neel, who begins with a discussion of the legacy of our human genome, and, as he phrases it, how "old genes have gone astray." His main thesis, however, is that gene therapy and, in general, an emphasis on the genetic basis of so-called "diseases of civilization"--for example, [End Page 327] diabetes, hypercholesterolemia, hypertension, and coronary heart disease--is not the best strategy for promoting population health. Rather, he advocates that nutritionists take a life-style approach--that is, behavioral modification of diet and exercise-- to these diseases, because it is more cost effective and ultimately has a larger public health impact. It is an interesting and refreshing perspective, expecially coming from a researcher who has spent most of his career studying the underlying genetic aspects of these diseases. Where this approach is weak, however, is in Neel's emphasis on life-style, as if we all live in a homogeneous society, where we simply have to modify our behavior and things will improve. What is missing in this argument is any recognition of structural barriers to good nutrition. For example, many Aboriginal people who suffer fron noninsulin dependent diabetes mellitus (NIDDM) do not have the economic means to buy nutritionally good food.
The article by L. Cordain is a fascinating and extremely thorough examination of the role of cereal grains in the human diet through evolutionary history up to the present. Cordain argues that since humans did not evolve with cereal grains in their diet, it is now inappropriate and perhaps nutritionally deleterious for most of humanity to be relying so heavily on them. What Cordain does not acknowledge in this article are the behavioral adaptations to cereal diets that have evolved since the Agricultural Revolution. For example, the Latin American tradition of combining foods, such as maize and beans, results in a combination of amino acids that produces a meal with complete protein and therefore compensates for protein deficiencies in each of these foods alone. Finally, Cordain does not address the current situation of a world population of 6 billion people on the planet. Currently, we are unable to provide enough cereal grain for much of humanity, let alone provide all humanity with high-quality animal protein. Clearly, the optimal diet in Cordain's view is unobtainable and unsustainable.
In the third paper J.C. Brand-Miller and J.C. Colagiuri coin what they call the "carnivore connection" to explain a modern epidemic of hyperinsulinemia. In a similar vein to the "thrifty gene" hypothesis, they argue that insulin resistance was once advantageous for humans, who were eating a high-protein, low-carbohydrate diet, but once the diet shifted to a highly refined carbohydrate diet, hyperinsulinemia was no longer beneficial and it now causes diseases such as NIDDM, coronary heart disease, and hypertension. They also point out that beyond the Agricultural Revolution and its radical change to the human diet, we must also consider the profound effects of the Industrial Revolution and the Post-Industrial diet with the proliferation of highly refined carbohydrates in the last centuries. The paper is thought provoking and their hypothesis is reasonable. What is problematic...