Tag Archives: Loren Cordain

Quote of the Day

….built into our genes is a blueprint for optimal nutrition—a plan that spells out the foods that make us healthy, lean, and fit.  Whether you believe the architect of that blueprint is God, or God acting throughout evolution by natural selection, or by evolution alone, the end result is still the same: We need to give our bodies the foods we were originally designed to eat.

Loren Cordain in The Paleo Diet

Lean and fit Australian Aborigine

Paleolithic Nutrition: Twenty-Five Years Later

Melvin Konner and S. Boyd Eaton wrote a review article for Nutrition in Clinical Practice that update’s their seminal New England Journal of Medicine  paleo nutrition article of 1985.  They took a fresh look at recent  data on modern hunter-gatherer societies as well as advances in anthropology. 

NEJM likely has much wider circulation, so it’s too bad the update wasn’t published there.

I’ve written previously about the history of the modern paleo movement.  I consider S. Boyd Eaton and Melvin Konner two of the founders. 

I wanted to share a few tidbits from the new article:

  • The transition from hunting/gathering to farming (about 10,000 year ago) saw a decrease in body size and robustness, plus evidence of nutritional stress
  • Modern humans migrated away from Africa between 50,000 and 100,000 years ago
  • Levels of muscular and aerobic fitness in ancestral groups are much higher than modern societies, with a concomittant higher level of calorie consumption
  • Average life expectancies in pre-industrial hunter-gatherer (H-G) groups was only 30-35 years, but much of this low number simply reflects high infant and child death rates
  • H-G deaths overwhelmingly reflect infectious diseases
  • H-G groups had a high degree of dependence on plant foods
  • Cooking has been important to humans for at least 230,000 years, if not longer
  • Fish and shellfish are more important food sources than these authors thought 25 years ago
  • Ancestral H-G groups derived 35 to 65% of diet (calories, I guess) from animal flesh
  • Game animals have more mono- and polyunsaturated fatty acids than supermarket meat
  • H-G diets are higher in fat than they once thought: the new range is 20 to 35% of calories
  • H-G diet omega-6: omega-3 ratio was 2:1, in contrast to the modern Western ratio of 10:1
  • H-G groups eat more protein than they once thought
  • Carbohydrate consumption of H-G groups varied from about 35 to 65% of calories.  (I’ve written elsewhere about the carb content of paleo diets.)
  • Nearly all H-G carbs are from vegetables and fruits, which have more favorable glycemic responses than grains and concentrated sugars
  • Uncultivated fruits and veggies have much more fiber than commercial ones (13 versus 4 g fiber per 100 g of food)
  • H-G diets have at least 70 g of fiber daily
  • Sodium in H-G diets is very low: 800 mg/day

The Diet-Heart Hypothesis is the idea that dietary total and saturated fat, and cholesterol, cause or contribute to atherosclerosis (hardening of the arteries), leading to heart attacks and strokes.  Konner and Eaton still believe the theory is valid for fats, but not cholesterol.  The latest evidence is that even total and saturated fat are minimally or unrelated to atherosclerosis

They also believe total fat, due to its caloric load, is an important contributor to obesity and type 2 diabetes.  (I agree that my be true if you eat a lot of carbs with fat.)

Konner and Eaton review the very few clinical studies—a grand total of four—that apply a paleo diet to modern humans.  Results support their theory that paleo-style eating has healthful metabolic effects.

Their conception of a paleo food pyramid is a base of high-fiber vegetables and fruits, the next tier up being meat/fish/low-fat dairy (!?) (all lean), then a possible tier for whole grain (admittedly very unusual), with a small peak of oils, fats, and refined carbohydrates.

They recommend high activity levels, including resistance exercise, flexibility, and aerobics, burning over 1,000 cals/day exclusive of resting metabolism.

They also seem to favor small amounts of alcohol—not generally considered paleo—to reduce heart disease risk, admitting that “…the HG model cannot answer all questions.”

Eaton and Konner suggest the following as the “estimated ancestral diet“:

  • Carbohydrates, % daily energy                 35-40
  • Protein, % daily energy                                 25-30
  • Fat, % daily energy                                          20-35
  • Added sugar, % daily energy                            2
  • Fiber, g/day                                                        >70
  • EPA and DHA*, g/day                                    0.7-6
  • Cholesterol, mg/day                                       500+
  • Vitamin C, mg/day                                           500
  • Vitamin D, IU/day                                4,000 (sunlight)
  • Calcium, mg/day                                       1,000-1,500
  • Sodium, mg/day                                         under 1,000
  • Potassium, mg/day                                         7,000

*Eicosapentaenoic acid and docosahexaenoic acid

Konner and Eaton call for more randomized controlled studies of the paleo diet.  These studies will need to define the paleo diet carefully.  Their definition is probably as good as any, if not the best.  Of course, the listed nutrients should come from minimally processed, natural foods.  We just need Loren Cordain‘s and Staffan Lindeberg‘s  input on a concensus definition of the paleo diet, then we’re ready to rock’n’roll.

Steve Parker, M.D.

Reference:

Konner, Melvin and Eaton, S. Boyd.  Paleolithic Nutrition: Twenty-Five Years LaterNutrition in Clinical Practice, 25 (2010): 594-602.  doi: 10.1177/0884533610385702

Eaton, S.B. and Konner, M.  Paleolithic nutrition: a consideration of its nature and current implicationsNew England Journal of Medicine, 312 (1985): 283-289.

 

Is the Paleo Diet Low-Carb?

Low-carb diet and paleo diet advocates often align themselves, even though S. Boyd Eaton’s 1988 version of the paleo diet doesn’t appear to be very low-carb at all: 46% of total calories from carbohydrate.  The standard American diet provides 50-55% of calories from carbohydrate.  Paleo proponents and low-carbers do share an affinity for natural, whole foods, and an aversion to grains, milk, and legumes. 

A 2010 article by Kuipers et al (reference below) sugggests that the East African Paleolithic diet derived, on average, 25-29% of calories from protein, 30-39% from fat, and 39-40% from carbohydrate.  That qualifies as low-carb.  Modern Western percentages for protein, fat, and carb are 15%, 33%, and 50%, respectively.

Loren Cordain and associates in 2000 suggested that Paleolithic diets may have derived about a third—22 to 40%—of calories from carbohydrate, based on modern hunter-gatherer societies. 

You can make a good argument that these paleo concepts are healthy: high physical activity, nonsmoking, consumption of natural whole foods while minimizing simple sugars and refined starches.  The paleo community is convinced that grains and legumes are harmful; many others disagree.  Also debatable are the roles of dairy, polyunsaturated to saturated fat ratio, low sodium, and high potassium.  Modern diets tend to be high-sodium and low-potassium, which may predispose to high blood pressure and heart trouble—diseases of modern civilization.

It appears that the average paleo diet may have derived about a third of calories from carbohydrate: that qualifies as low-carb.

For more on the paleo diet and lifestyle, visit Robb Wolf’s website, Mark’s Daily Apple, and Archevore

Steve Parker, M.D.

References:

Kuipers, R., Luxwolda, M., Janneke Dijck-Brouwer, D., Eaton, S., Crawford, M., Cordain, L., & Muskiet, F. (2010). Estimated macronutrient and fatty acid intakes from an East African Paleolithic diet British Journal of Nutrition, 1-22 DOI: 10.1017/S0007114510002679.  Note that one of the authors is Loren Cordain.  Good discussion of various Paleolithic diets.

Eaton, S., Konner, M., & Shostak, M. (1988). Stone Agers in the fast lane: Chronic degenerative diseases in evolutionary perspective. The American Journal of Medicine, 84 (4), 739-749 DOI: 10.1016/0002-9343(88)90113-1

Cordain, L., et al.  Plant-animal subsistance ratios and macronutrient energy estimations in worldwide hunter-gatherer dietsAmerican Journal of Clinical Nutrition, 71 (2000): 682-692.

Paleo Diet Revival Story

My superficial reading of the paleo diet literature led me to think Loren Cordain, Ph.D., was the modern originator of this trend, so I was surprised to find an article on the Stone Age diet and modern degenerative diseases in a 1988 American Journal of Medicine by S. Boyd Eaton, M.D., et al.  Dr. Cordain started writing about the paleo diet around 2000, I think.

What’s So Great About the Paleolithic Lifestyle?

In case you’re not familiar with paleo diet theory, here it is.  The modern human gene pool has changed little over the last 50,000 years or so, having been developed over the previous one or two million years.  Darwins’ concept of Natural Selection suggests that organisms tend to thrive if they adhere to conditions present during their evolutionary development.  In other words, an organism is adapted over time to thrive in certain environments, but not others.

The paleo diet as a healthy way to eat appeals to me.  It’s a lifestyle, really, including lots of physical activity, avoidance of toxins, adequate sleep, etc. 

The Agricultural Revolution (starting about 10,000 years ago) and the Industrial Revolution (onset a couple centuries ago) have produced an environment and food supply vastly different from that of our Paleolithic ancestors, different from what Homo sapiens were thriving in for hundreds of thousands of years.  That discordance leads to obesity, type 2 diabetes, atherosclerosis, high blood pressure, and some cancers.  Or so goes the theory.

What’s the Paleolithic Lifestyle?  (according to Eaton’s 1988 article)

  • Average life expectancy about half of what we see these days
  • No one universal subsistence diet
  • Food: wild game (lean meat) and uncultivated vegetables and fruits (no dairy or  grain)
  • Protein provided 34% of calories (compared to about 12% in U.S. in 1988)
  • Carbohydrate provided 46% of calories (only a  tad lower than what we eat today)
  • Fat provided 21% of calories (42% today)
  • Little alcohol, but perhaps some on special occasions (honey and wild fruits can undergo natural fermentation) , compared to 7-10% of calories in U.S. today [I didn’t know it was that high]
  • No tobacco
  • More polyunsaturated than saturated fats (we ate more saturated than polyunsaturated fat, at least in 1988)
  • Minimal simple sugar availability except when honey in season
  • Food generally was less calorically dense compared to modern refined, processed foods
  • 100-150 grams of dietary fiber daily, compared to 15-20 g today
  • Two or three times as much calcium as modern Americans
  • Under a gram of sodium daily, compared to our 3 to 7 grams.
  • Much more dietary potassium than we eat
  • High levels of physical fitness, with good strength and stamina characteristic of both sexes at all ages achieved through physical activity

[These points are all debatable, and we may have better data in 2011.]

The article authors point out that recent unacculturated native populations that move to a modern Western lifestyle (and diet) then see much higher rates of obesity, diabetes, atheroslcerosis, high blood pressure, and some cancers.  “Diseases of modern civilization,” they’re called.  Cleave and Yudkin wrote about this in the 1960s and ’70s, focusing more on the refined carbohydrates in industrial societies rather than the entire lifestyle. 

Paleo diet proponents agree that grains are not a Paleolithic food.  The word “grain” isn’t in Eaton’s article.  The authors don’t outline the sources of Paleolithic carbs: tubers and roots, fruits, nuts, and vegetables, I assume.  Legumes and milk are probably out of the question, too.

The Paleolithic Prescription: A Program of Diet and Exercise and a Design for Living was published in 1988 by Harper & Row (New York).  The authors are S. Boyd Eaton, M. Shostak, and M. Konner. 

Eaton and Konner are also the authors of “Paleolithic nutrition: A consideration of its nature and current implications.”  in New England Journal of Medicine, 312 (1985): 283-289.

Mat Lalonde, Ph.D., in an interview with Jimmy Moore suggested that Cordain would credit S. Boyd Eaton, M.D., with the recent trendiness of the paleo diet.

Paul Jaminet wrote at one of my other blogs: “In 1975 a gastroenterologist named Walter L. Voegtlin published a book called The Stone Age Diet arguing for a low-carb Paleo diet.  S. Boyd Eaton was second.  Not much happened for a time, then it picked up in the late 1990s and early 2000s.  Ray Audette with Neanderthin was first to market…Oh, and I forgot Jan Kwasniewski’s Optimal Diet, which was first published in Poland around 1970.  Not exactly a Paleo diet, but close.

If you have evidence that the “modern paleo” diet goes back further than this, please leave a comment.

Steve Parker, M.D.

References:

Kuipers, R., Luxwolda, M., Janneke Dijck-Brouwer, D., Eaton, S., Crawford, M., Cordain, L., & Muskiet, F. (2010). Estimated macronutrient and fatty acid intakes from an East African Paleolithic diet British Journal of Nutrition, 1-22 DOI: 10.1017/S0007114510002679.  Note that one of the authors is Loren Cordain.  Good discussion of various Paleolithic diets.

Eaton, S., Konner, M., & Shostak, M. (1988). Stone agers in the fast lane: Chronic degenerative diseases in evolutionary perspective The American Journal of Medicine, 84 (4), 739-749 DOI: 10.1016/0002-9343(88)90113-1

Cordain, L., et al.  Plant-animal subsistance ratios and macronutrient energy estimations in worldwide hunter-gatherer dietsAmerican Journal of Clinical Nutrition, 71 (2000): 682-692.