Sunday, April 8, 2012

Precision Nutrition - Paleo for Everyone: Using Change Psychology Instead of Nutritional Dogmatism

I am a general supporter of the Paleo Diet, Caveman Diet, Primal Living, or Ancestral Diet approaches to nutrition (I probably missed a few of the various other names for eating a "real" food diet). The basic premise, for those who avoid all diets as silly fads, is that until about 10,000 years ago and the rise of agrarian culture (permanent settlements and farming grains for food), we ate only meats, fish, nuts, fruits, and vegetables, with the occasional foray into fungi (mushrooms) and insects (yum, crunchy protein). We did not eat grains, consume dairy of any kind, or (for the most part) each things that grow underground (tubers, etc.).

Huge mounds of research show that when we do eat this way, we do not suffer from many of the modern diseases that plague us now - diabetes, heart disease, obesity, and chronic inflammation, to name only a few).

To be honest, I do not eat fully primal or paleo - I do eat cottage cheese and regular cheese, as well as the very occasional grain food and legumes. But my diet is about 75% paleo and my health is excellent. When I want to lean out, I reduce fruits and eliminate all grains, legumes, and cut way back on dairy.

I have chosen to post this here, rather than at IOC, because men tend to fare better on Paleo type diets than women, which I think comes down to hormonal and metabolic differences - my female clients tend (not always, but tend) to need more carbohydrates than male clients. It may also be an adaptation issue - among my female clients, breads and sugars have played a larger role in their dietary history. Still, that's all speculation on my part.

Here are a few articles from Loren Cordain (his site contains an extensive list of peer-reviewed articles on which he was an author), the leading researcher in this field.

Ramsden CE, Faurot KR, Carrera-Bastos, P, Sperling LS, de Lorgeril M, Cordain L. Dietary fat quality and coronary heart disease  prevention: a unified theory based on evolutionary, historical, global and modern perspectives. Curr Treat Options Cardiovasc Med; 2009;11:289-301.

O’Keefe J.H., Cordain L.  Cardiovascular disease as a result of a diet and lifestyle at odds with our Paleolithic genome: how to become a 21st century hunter-gatherer. Mayo Clin Proc; 2004;79:101-108.

Lindeberg S, Cordain L, Eaton B.  Biological and clinical potential of a Palaeolithic diet. J Nutr Environ Med; 2003;13:149-160.
Purpose: To explore the possibility that a Palaeolithic diet, i.e. one that corresponds to what was available in any of the ecological niches of pre-agricultural humans (1.5 million–10,000 years BP), is optimal in the prevention of age-related degenerative disease. Design: Literature review. Materials and Methods: Between 1985 and December 2002, more than 200 scientific journals in medicine, nutrition, biology and anthropology were systematically screened for relevant papers. Computer-based searches and studies of reference lists in journals and books provided a vast number of additional papers. Results: Increasing evidence suggests that a Palaeolithic diet based on lean meat, fish, vegetables and fruit may be effective in the prevention and treatment of common Western diseases. Avoiding dairy products, margarine, oils, refined sugar and cereals, which provide 70% or more of the dietary intake in northern European populations, may be advisable. Atherosclerosis is highly dependent on dietary manipulation in animal experiments. Atherogenic dietary factors include fat (any type) and casein, and hypothetically cereals. Stroke, ischaemic heart disease and type 2 diabetes seem largely preventable by way of dietary changes in a Palaeolithic direction. And insulin resistance, which may have far- reaching clinical implications as a cause of unregulated tissue growth, may also respond to an ancestral diet. Conclusions: Lean meat, fish, vegetables and fruit may be optimal, rather than a strictly vegetarian diet, in the prevention of cardiovascular disease, diabetes and insulin resistance.
Cordain L, Eaton SB, Brand Miller J, Mann N, Hill K.  The paradoxical nature of hunter-gatherer diets: Meat based, yet non-atherogenic. Eur J Clin Nutr; 2002;56 (suppl 1):S42-S52.
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 = 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 = 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 ?-6/?-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.
There are clearly good reasons not to consume a meat-based diet (corporate cattle farms and environmental damage not least on the list), including the problem with the fat profile of farmed meat, which is very unhealthy compared to open range and grass-fed beef. We see the same issue in farmed-fish (like salmon) as well.

Still, it's possible to eat paleo and eat with a conscience (sort of - shop at a kosher deli) and eat healthy meat and fish.

Recently, the PaleoFX Conference (Ancestral Momentum - Theory to Practice Symposium) brought together leaders in exercise, nutrition, and research, including Krista Scott-Dixon, who works for John Berardi's Performance Nutrition - Berardi is a leader in exercise nutrition research and praxis.

They posted a three-video series on their view of the paleo approach (they prefer primal). Follow the links to watch the video presentations - be sure to read the post as well.

Paleo for Everyone - Using Change Psychology Instead of Nutritional Dogmatism

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