The paradoxical nature of hunter-gatherer diets: meat-based, yet non-atherogenic

Abstract

Objective: Field studies of twentieth century hunter-gathers (HG) showed them to be generally free of the signs and symptoms of cardiovascular disease (CVD). Consequently, the characterization of HG diets may have important implications in designing therapeutic diets that reduce the risk for CVD in Westernized societies. Based upon limited ethnographic data (n ¼ 58 HG societies) and a single quantitative dietary study, it has been commonly inferred that gathered plant foods provided the dominant energy source in HG diets. Method and Results: In this review we have analyzed the 13 known quantitative dietary studies of HG and demonstrate that animal food actually provided the dominant (65%) energy source, while gathered plant foods comprised the remainder (35%). This data is consistent with a more recent, comprehensive review of the entire ethnographic data (n ¼ 229 HG societies) that showed the mean subsistence dependence upon gathered plant foods was 32%, whereas it was 68% for animal foods. Other evidence, including isotopic analyses of Paleolithic hominid collagen tissue, reductions in hominid gut size, low activity levels of certain enzymes, and optimal foraging data all point toward a long history of meat-based diets in our species. Because increasing meat consumption in Western diets is frequently associated with increased risk for CVD mortality, it is seemingly paradoxical that HG societies, who consume the majority of their energy from animal food, have been shown to be relatively free of the signs and symptoms of CVD. Conclusion: The high reliance upon animal-based foods would not have necessarily elicited unfavorable blood lipid profiles because of the hypolipidemic effects of high dietary protein (19 -35% energy) and the relatively low level of dietary carbohydrate (22 -40% energy). Although fat intake (28 -58% energy) would have been similar to or higher than that found in Western diets, it is likely that important qualitative differences in fat intake, including relatively high levels of MUFA and PUFA and a lower o-6=o-3 fatty acid ratio, would have served to inhibit the development of CVD. Other dietary characteristics including high intakes of antioxidants, fiber, vitamins and phytochemicals along with a low salt intake may have operated synergistically with lifestyle characteristics (more exercise, less stress and no smoking) to further deter the development of CVD.

Should animal fats be back on the table? A critical review of the human health effects of animal fat

“…Some humans still occupy this niche, and their hunting and gathering habits have been documented (Murdock 1967;Cordain et al 2002a;Rouja et al 2003). Organs and fat were generally preferred to lean meat by these hunter-gatherers who were well aware of the value of eating animal fat: the side effects of eating only lean meat have been replicated in the laboratory and they include diarrhoea and unsatisfied hunger (Stefansson 1912;McClellan and Du Bois 1930;Phinney 2004).…”

The ancestral human diet: what was it and should it be a paradigm for contemporary nutrition?

“…In the USA total PUFA consumption is estimated to average about 15 g/d, with n-6 PUFA intake about ten times that of n-3 PUFA (Institute of Medicine, 2002). The best available estimate of ancestral human intake suggests that total PUFA intake was nearly twice present levels, almost entirely a result of more n-3 PUFA so that n-6: n-3 was closer to unity, perhaps 2: 1 Cordain et al 2002a). Current US recommendations are quite different, about 8: 1 (Institute of Medicine, 2002).…”

“…5 to 2 . 0 Cordain et al 2002a). The Institute of Medicine (2002) recommends that EPA and DHA intake is £10% total n-3 PUFA intake.…”

The Metabolic Plant Feedback Hypothesis: How Plant Secondary Metabolites Nonspecifically Impact Human Health

“…1). A pastoralist diet resembles a hunter-gatherer diet, which consists of 65% animal food (total energy) and the remaining 35 % coming from wild plant sources [30], including starchy plants. Typical carbohydrate farming diets consist of about 45-65% carbohydrates (total energy).…”

“…Clearly, the diversity of the total bioavailable dietary plant natural products and metabolites thereof remains unknown and varies with diet, culture, and lifestyle [58]. While numerous and, in part, conflicting health claims about food-derived vegetable antioxidants and fatty acids have been made [59][60][61][62][63][64][65][66][67][68], there is no doubt that the use of dietary plants coevolved with the mammalian diet within a food-medicine continuum [30][31][32][33]. The intriguing question is why humans eat what they eat, and how this may affect health and fitness through selection and epigenetic mechanisms [14,15,[69][70][71].…”