Below Is a recent interview conducted by Olga Tymanowska with Dr. Loren Cordain:
Olga: In 1985 Drs. Eaton and Konnel published an article on the Paleolithic
diet in the NEJM. They expressed the opinion that diet had little direct
influence on the genetic composition of humanity. In your book ‘The Paleo
Diet’ you claim the same. What evidence do you have to prove it? Not long
ago it was possible to base a full theory of race formation on the
diametrically opposite view. What has changed?
Dr. Cordain: The Eaton and Konner paper is more than 25 years old. The basic underlying message is essentially correct, but certain advances in our understanding of gene expression (particularly epigenetics) have slightly altered their original message. How specific foods or nutrients alter the human genome is poorly understood, as well as the extent to which the current human genome has been modified by dietary changes over the past 2.5 million years. World wide genomic sweeps support Eaton and Konner’s original thesis that the human genome has changed little over the past 60,000 years, whereas our diets have changed dramatically.
Olga: You say that we are genetically programmed for the paleolithic
nutritional pattern. This is controversial because it is contrary to
contemporary opinion about proper human nutrition, such as low-fibre,
low-calorie or low-carbohydrate diets. Perhaps the single most
controversial point you make is the huge intake of protein recommended.
What evidence do you have that the diet is healthy, particularly since it
is contrary to the notion of a well-balanced diet?
Dr. Cordain: The notion that our present day genome was selected during the Paleolithic era is not controversial among evolutionary biologists or geneticists studying the human genome in diverse world wide groups. I suggest you read the following article that recently appeared in Scientific American: Pritchard JK. How we are evolving. Sci Am 303(4) (October 2010): 40–47. Very few changes in the human genome known to be caused by dietary selective pressures are known. The most notorious is adult lactase persistence (ALP), of which about 35 % of the world’s population maintain.
Five experimental studies in humans have demonstrated that contemporary Paleo diets are therapeutic and even produce superior health effects than the Meditteranean diet in type 2 diabetics. You may want to read the following papers:
O’Dea K. Marked improvement in carbohydrate and lipid metabolism in diabetic Australian aborigines after temporary reversion to traditional lifestyle. Diabetes 33(6) (1984): 596–603.
Osterdahl M, Kocturk T, Koochek A, and Wandell PE: Effects of a short-term intervention with A Ppaleolithic diet in healthy volunteers. Eur J Clin Nutr 62(5) (2008): 682–685.
Lindeberg S, Jonsson T, Granfeldt Y, Borgstrand E, Soffman J, Sjostrom K, and Ahren B. A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease. Diabetologia 50(9) (2007): 1795–1807.
Jönsson T, Granfeldt Y, Erlanson-Albertsson C, Ahren B, and Lindeberg S. A Paleolithic diet is more satiating per calorie than a Mediterranean-like diet in individuals with ischemic heart disease. Nutr Metab (Lond) 7(1) (November 30, 2010): 85.
Frassetto LA, Schloetter M, Mietus-Synder M, Morris RC, Jr., and Sebastian A. Metabolic and physiologic improvements from consuming a Ppaleolithic, hunter-gatherer type diet. Eur J Clin Nutr (2009).
Olga: You state that the Neolithic revolution began only 10,000 years ago and
cannot be compared with the time 2.5 million years ago when people ate
lean meat, fruits and vegetables. Is this eating pattern optimal for us
today, when we know that there are differences between individuals and
what is good for one person is not necessarily good for others?
Dr. Cordain: Clearly, not one size does not fit all. 65 % of the world’s population are lactose intolerant and cannot drink milk without GI upset, yet the USDA My Plate program advocates dairy products for all. Recent randomized controlled trials in children show that high milk diets cause insulin resistance, and numerous large scale studies from Europe indicate that milk drinking in infants and young children increase the risk for type 1 diabetes. About 1 % of the US population has celiac disease and recent estimates show that about 20 % maintain gluten sensitivity — yet USDA recommendations advocate wheat eating for the entire population. Hence, modern day Paleo Diets represent the starting point for good human nutrition, and modifications can be made individually.
Olga: We have certain evidence that the Paleo diet can be beneficial for
humans. However the field of nutrigenomics, which has developed rapidly in
recent years, isassociated with the idea of personalized nutrition based
on genotype. Is it possible if not to reconcile, then at least to find
some common ground between these two very different approaches as to what
the ideal nutritional pattern should be?
Dr. Cordain: Yes. Human dietary requirements are determined genetically, and our genome was shaped eons ago before the advent of modern processed foods, cereal grains and dairy products.
Olga: You write about the balance between acid and alkaline intake as
fundamental to a healthy diet. Today we no longer have available many of
the plants which would have existed 2.5 million years ago, when roughly
200 different kinds of plants would have been consumed. Today we no longer
have so much choice when substituting for vegetables the cereals to which
we have become accustomed. So how can we follow your eating
Dr. Cordain: All fruits and vegetables whether domesticated or wild yield a net acid load to the kidneys whereas cereal grain are net acid yielding. The displacement of fruits and veggies in the diet by cereals promotes a chronic low level acidosis and the variety of health problems known to occur with net acid yielding diets.
Olga: Some nutritionists claim that we cannot recover from the past that
which has been lost, and point out that humans now live three times as
long as Paleolithic peoples, and imitating their diet would not extend
life expectancy. They also claim that 2.5 million years ago, people would
eat almost anything they could find, and it is this variety which is
missing from the modern diet. Would you agree?
Dr. Cordain: The only dietary manipulation known to extend lifespan is caloric reduction. The intent of contemporary Paleo diets is to improve health and reduce the risk of chronic diseases of civilization which run rampant now in all westernized countries including Poland. In western diets the following food items (refined sugars, cereals, refined vegetable oils, alcohol and dairy products products) comprise 70 % of the total caloric intake, whereas fruits and vegetables comprise less than 10 % of our daily food. I agree that by reducing refined sugars, refined flours and processed foods and replacing them with more fresh fruits, vegetables, meats and seafood, the western world’s peoples (including Poland and the US) could dramatically reduce the incidence of the chronic degenerative diseases that afflict us all.
Olga: You recommend eating lots of fruit, but fruit today contains 4-6 times
more sugar than that eaten by Paleolithic peoples. You also suggest that
we should stop drinking milk, which is high in calcium. Would it be
well-balanced diet? What are the advantages?
Dr. Cordain: The quantity of sugar in fresh fruits pales in comparison to the amount of sugar in processed foods. At my website, I provide a table of the amounts and types of sugars in all fruits commonly available in the western world. Except for calcium, contemporary Paleo diets are much richer in all nutrients required by humans and vastly surpass the Food Pyramid in all vitamins and minerals (see attached paper). The reason for this is that fresh, fruits, veggies, meats and seafood are much more nutrient dense than whole grains, dairy products and processed foods. If diets are net base yielding (Paleo Diets), humans reach calcium homostasis at lower calcium intakes without the need for dairy.
Loren Cordain, Ph.D., Professor Emeritus