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Physical inactivity (and unhealthy nutrition) has distorted body composition and, in turn, reordered the proportions of myocyte and adipocyte insulin receptors. Insulin acting on adipocyte receptors produces less glucose uptake than does comparable interaction with myocyte receptors. Accordingly, in individuals with disproportionate muscle/fat composition, any given glucose load requires greater-than-normal pancreatic insulin secretion for adequate disposal. This hyperinsulinemia then becomes the leading cause of type 2 diabetes (T2DM) as insulin-sensitive tissues become desensitized. Because T2DM is rooted in potentially reversible lifestyle factors, rather than focusing on the intricacies of glucoregulation at the molecular level and on testing new drugs to control blood sugar, this article calls for a new prevention and treatment paradigm, in which exercise and weight control are essential and for which an inexpensive and acceptably accurate measure of body muscle and fat proportions is needed.

Beginning in 1985, we and others presented estimates of hunter‐gatherer (and ultimately ancestral) diet and physical activity, hoping to provide a model for health promotion. The Hunter‐Gatherer Model was designed to offset the apparent mismatch between our genes and the current Western‐type lifestyle, a mismatch that arguably affects prevalence of many chronic degenerative diseases. The effort has always been controversial and subject to both scientific and popular critiques. The present article (1) addresses eight such challenges, presenting for each how the model has been modified in response, or how the criticism can be rebutted; (2) reviews new epidemiological and experimental evidence (including especially randomized controlled clinical trials); and (3) shows how official recommendations put forth by governments and health authorities have converged toward the model. Such convergence suggests that evolutionary anthropology can make significant contributions to human health. [ABSTRACT FROM AUTHOR]

Modeling ancestral dietary pattern is vital in understanding current human nutritional needs. A comparative study indicates that an ordinary Paleolithic diet is analogous to presently recommended diets in East Asia, the Mediterranean, and the one designed by the American Health Association in terms of minimal saturated fatty acid content. Stone Agers' consumption of vegetable and fruits is three times more than the US. Micronutrient intake is higher yet of moderate extent whereas protein and fiber are considerably higher than the present diet.

A quarter century has passed since the first publication of the evolutionary discordance hypothesis, according to which departures from the nutrition and activity patterns of our hunter-gatherer ancestors have contributed greatly and in specifically definable ways to the endemic chronic diseases of modern civilization. Refinements of the model have changed it in some respects, but anthropological evidence continues to indicate that ancestral human diets prevalent during our evolution were characterized by much lower levels of refined carbohydrates and sodium, much higher levels of fiber and protein, and comparable levels of fat (primarily unsaturated fat) and cholesterol. Physical activity levels were also much higher than current levels, resulting in higher energy throughput. We said at the outset that such evidence could only suggest testable hypotheses and that recommendations must ultimately rest on more conventional epidemiological, clinical, and laboratory studies. Such studies have multiplied and have supported many aspects of our model, to the extent that in some respects, official recommendations today have targets closer to those prevalent among hunter-gatherers than did comparable recommendations 25 years ago. Furthermore, doubts have been raised about the necessity for very low levels of protein, fat, and cholesterol intake common in official recommendations. Most impressively, randomized controlled trials have begun to confirm the value of hunter-gatherer diets in some high-risk groups, even as compared with routinely recommended diets. Much more research needs to be done, but the past quarter century has proven the interest and heuristic value, if not yet the ultimate validity, of the model. (Nutr Clin Pract. 2010;25:594-602) [ABSTRACT FROM PUBLISHER]

At present, human genes and human lives are incongruent, especially in affluent Western nations. When our current genome was originally selected, daily physical exertion was obligatory; our biochemistry and physiology are designed to function optimally in such circumstances. However, today''s mechanized, technologically oriented conditions allow and even promote an unprecedentedly sedentary lifestyle. Many important health problems are affected by this imbalance, including atherosclerosis, obesity, age-related fractures and diabetes, among others. Most physicians recognize that regular exercise is a critical component of effective health promotion regimens, but there is substantial disagreement about details, most importantly volume: how much daily caloric expenditure, as physical activity, is desirable. Because epidemiology-based recommendations vary, often confusing and alienating the health-conscious public, an independent estimate, arising from a separate scientific discipline, is desirable, at least for purposes of triangulation. The retrojected level of ancestral physical activity might meet this need. The best available such reconstruction suggests that the World Health Organization''s recommendation, a physical activity level of 1.75 (∼2.1 MJ (490 kcal)/d), most closely approximates the Paleolithic standard, that for which our genetic makeup was originally selected. [Copyright &y& Elsevier]

The proposal that Late Paleolithic (50,000–10,000 BP) ancestral experience might serve as a model for prevention research and even, if justified by experiment, as a paradigm for health promotion recommendations is sometimes discounted, before critical assessment, because of reservations based on unjustified preconceptions. Most often such biases involve comparative life expectancy, potential genetic change since agriculture, the heterogeneity of ancestral environments, and/or innate human adaptability. This paper examines these topics and attempts to show that none of them justifies a priori dismissal of the evolutionary approach to preventive medicine. Evolutionary health promotion may ultimately be invalidated because of its falsification by experiment or because another theory accords better with known facts, but these commonly held prejudices should not forestall its thoughtful consideration and investigative evaluation. [Copyright &y& Elsevier]

Health promotion''s promise is enormous, but its potential is, as yet, unmatched by accomplishment. Life expectancy increases track more closely with economic prosperity and sanitary engineering than with strictly medical advances. Notable achievements in the past century—the decreased incidences of epidemic infections, dental caries, and stomach cancer—are owed to virologists, dentists, and (probably) refrigeration more than to physicians. Prevention speaks against tobacco abuse with a single voice, but in many other areas contradictory research findings have generated skepticism and even indifference among the general public for whom recommendations are targeted. Health promotion''s shortcomings may reflect lack of an overall conceptual framework, a deficiency that might be corrected by adopting evolutionary premises: (1) The human genome was selected in past environments far different from those of the present. (2) Cultural evolution now proceeds too rapidly for genetic accomodation—resulting in dissociation between our genes and our lives. (3) This mismatch between biology and lifestyle fosters development of degenerative diseases. These principles could inform a research agenda and, ultimately, public policy: (1) Better characterize differences between ancient and modern life patterns. (2) Identify which of these affect the development of disease. (3) Integrate epidemiological, mechanistic, and genetic data with evolutionary principles to create an overarching formulation upon which to base persuasive, consistent, and effective recommendations. [Copyright &y& Elsevier]

A letter to the editor is presented in response to two articles, one on plant-animal subsistence ratios and macronutrient energy estimates in hunter gatherer diets by L. Cordain and other on hunter-gatherer diets by Katherine Milton in a 2000 issue along with the authors' response to the same.

A letter to the editor and a response from the authors of the article "Plant-animal subsistence ratios and macronutrient estimations in worldwide hunter-gatherer diets" in the previous issue are presented.

Discusses how reproductive experiences for women in modern Western nations differ from those of women in hunting and gathering societies. Comparative reproductive considerations; Reproductive risk factors for cancer; Lifestyles and reproductive patterns; Extrareproductive factors.

Presents information on procedures employed for the diagnosis of extrahepatic biliary obstruction in patients with jaundice. Application of cholangiography; Types of radiopharmaceuticals used for the diagnosis of jaundice by isotopic imaging; Benefits offered by percutaneous cholangiography.