John McDougall, M.D., whom I’m embarrassed to say I used to take seriously, has written an article attacking the concept of paleo eating: The Paleo Diet Is Uncivilized (And Unhealthy and Untrue). (Hat tip: Ray Sawhill.) McDougall advocates a vegetarian, low-fat diet, and has become blinded by his ideology, which is the most charitable interpretation of his article. It deserves a refutation. Excerpts from his article in block quotes.
Low-carbohydrate (low-carb) diets are fueling the destruction of human health and our planet Earth.
No evidence for either claim. Overpopulation is the obvious cause of environmental decay. The number of people following low-carb diets is so minuscule as to be insignificant to the environment.
The original Atkins Diet is the ultimate in low-carb eating. This diet works by starving the human body of carbohydrates in order to induce a state of illness (ketosis), which can result in weight loss. People become too sick to eat too much.
Dr. McDougall is confused – again, to be charitable. He’s confusing a completely natural and healthy metabolic state, ketosis, with a pathological condition called diabetic ketoacidosis. Most of our paleo ancestors were likely in a state of ketosis a good deal of the time, and they were arguably much healthier than us. One also enters a state of ketosis after an overnight fast. Nothing unhealthy about it at all.
In an attempt to remedy the obvious harms to human health caused by very low-carb eating, apologists (including the Atkins Nutritionals) have added fruits and non-starchy vegetables to their programs. This effort is supposed to disguise, and compensate for, the unhealthy effects of consuming animal foods at every meal.
Atkins, the paleo crowd, and every low-carb advocate I’ve ever read have never advocated zero-carb or omitting fruits and vegetables. Hunter-gatherers ate them. McDougall is dishonest here.
The Paleo Diet book (revised 2011) is “the bible” for followers of this approach (page numbers from this book are found in parenthesis in this article).
Not really. Cordain was an early advocate, but a number of other writers have become better known advocates of paleo than he.
With the development of agriculture about 10,000 years ago, “Paleo experts” teach that human health and longevity plummeted. By no coincidence, the Agriculture Revolution marks the dawn of civilization. “Civilization” encompasses our advanced state of intellectual, cultural, and material development, marked by progress in the arts, music, sciences, languages, writing, computers, transportation, and politics.
Does McDougall have any evidence that what “paleo experts teach” regarding the health effects of agriculture is wrong? No, because they’re right. Agriculture caused a massive increase in heart disease, arthritis, tooth decay, probably cancer, and a definite loss of stature, all as compared to the paleo era preceding it. Why McDougall is trying to obfuscate the issue of diet by bringing in music, the sciences, etc., I don’t know – well, actually I do. Is he saying that primitive humans couldn’t possibly be in better health than civilized humans? if he is, he’s dead wrong.
Primates, including humans, have practiced hunting and gathering for millions of years. I know of no large populations of primates who have been strict vegans (ate no animal foods at all). However, plants have, with very few exceptions, provided the bulk of the calories for almost all primates. This truth has been unpopular in part because of a well-recognized human trait, sexism. Grandparents, women, and children did the gathering, while men hunted. Glory always goes to the hunters.
First, he lumps all primates from lemurs to gorillas to humans, together. Absurd. Then he notes that strict vegetarianism does not occur in primates, yet he advocates the practice. Next he uses shaming language against the human race, accusing it of “sexism”, with no evidence.
When asked about the commonly held idea that ancient people were primarily meat-eaters, the highly respected anthropologist, Nathanial Dominy, PhD, from Dartmouth College responded, “That’s a myth. Hunter-gathers, the majority of their calories come from plant foods…meat is just too unpredictable.” After studying the bones, teeth, and genetics of primates for his entire career as a biological anthropologist, Dr. Dominy, states, “Humans might be more appropriately described as ‘starchivores.’”
Again, evidence? Modern hunter-gatherers do get many of their calories from plants, but they have been pushed into marginal lands by the massive population growth attributable to agriculture – the last item something that McDougall micht want to investigate, since he’s worried about environmental degradation. No agriculture = no population growth.
Paleo diet proponents spare no effort to ignore and distort science. The general public is at their mercy until they look for themselves at recent publications from the major scientific journals:
* Research published in the journal Nature (on June 27, 2012) reports that almost the entire diet of our very early human ancestors, dating from 2 million years ago, consisted of leaves, fruits, wood, and bark—a diet similar to modern day chimpanzees.
Does McDougall – or anyone else – claim that the diet of our “very early human ancestors” of two million years ago is exactly what we’re designed to eat? They had much smaller brains than we do, were only adapted to living in the tropics, and much evolution has occurred since then. And humans are not chimpanzees.
* According to research presented in a 2009 issue of Science, people living in what is now Mozambique, along the eastern coast of Africa, may have followed a diet based on the cereal grass sorghum as long as 105,000 years ago.
“May”, and in any case that’s one datum, and nothing there says that they didn’t eat lots of meat. Eskimos ate no grains and an abundance of meat – and that’s not just one data point – but Dr. McDougall wants to dismiss that. What sort of health were these early Madagascarans in?
* Research presented in a 2011 issue of Proceedings of the National Academy of Science shows that even the Neanderthals ate a variety of plant foods; starch grains have been found on the teeth of their skeletons everywhere from the warm eastern Mediterranean to chilly northwestern Europe. It appears they even cooked, and otherwise prepared, plant foods to make them more digestible—44,000 years ago.
Strawman: who has denied that Neanderthals ate plants?
* A 2010 issue of the Proceedings of the National Academy of Science reported that starch grains from wild plants were identified on grinding tools at archeological sites dating back to the Paleolithic period in Italy, Russia, and the Czech Republic. These findings suggest that processing vegetables and starches, and possibly grinding them into flour, was a widespread practice in Europe as far back as 30,000 years ago, or even earlier.
“Suggest” – perhaps, but nothing indicates that these grains formed a substantial part of the diet or whether they were consumed only seasonally. Optimal foraging theory states that “organisms forage in such a way as to maximize their net energy intake per unit time. In other words, they behave in such a way as to find, capture and consume food containing the most calories while expending the least amount of time possible in doing so.” Unfortunately for vegetarian advocates, foraging for wild fruits, vegetables, and maybe grains isn’t optimal for survival, but hunting animals for meat is.
Dr. Cordain writes, “For most of us, the thought of eating organs is not only repulsive, but is also not practical as we simply do not have access to wild game.” (p 131). In addition to the usual beef, veal, pork, chicken, and fish, a Paleo follower is required to eat; alligator, bear, kangaroo, deer, rattlesnake, and wild boar are also on the menu. Mail-order suppliers for these wild animals are provided in his book.
I don’t find eating organs to be repulsive, and while I have eaten rattlesnake – tastes like chicken! – I’m a stranger to the other stuff. Don’t what McDougall’s point is here. Most humans in history haven’t had any problem with organ meats.
For most of us the thought of eating bone marrow and brains is repulsive. [Bone marrow repulsive? Why?] But it gets worse.
No mention is made by Paleo experts about the frequent and habitual practices of nutritional cannibalism by hunter-gather societies. (Nutritional cannibalism refers to the consumption of human flesh for its taste or nutritional value.) Archeologists have found bones of our ancestors from a million years ago with de-fleshing marks and evidence of bone smashing to get at the marrow inside; there are signs that the victims also had their brains eaten. Children were not off the menu. And we are supposed to eat the favorite meats of our uncivilized, pre-Agriculture Revolution, hunter-gather, ancestors?
God, this is getting ridiculous. No one is advocating the high levels of war and strife of the paleos, or advocating living in caves either.
By nature, the Paleo Diet is based on artery-clogging saturated fats and cholesterol, and bone-damaging, acidic proteins from animal foods.
And yet, one of McDougall’s very links leads to this: The atherogenic potential of dietary carbohydrate. From the article’s abstract:
High-carbohydrate nutrition is shown to have the ability to induce vascular inflammation and plaque formation through an insulin-mediated activation of the RAS, growth factors, cytokines, the SNS, and C-reactive protein and to cause an atherogenic lipid profile in normal humans. Epidemiologic studies as well as studies in experimental animals corroborate an important role of dietary carbohydrate in atherogenesis.
High-carbohydrate diets, particularly in the form of high-glycemic index carbohydrate, have the ability to directly induce atherosclerosis. Based on anthropologic facts, the reason for these dietary-induced, insulin-mediated, atherogenic metabolic perturbations are suggested to be an insufficient adaptation to starch and sugars during human evolution. Restriction of insulinogenic food (starch and sugars) may help to prevent the development of atherosclerosis, one of the most common and costliest human diseases. [emphasis added]
Respected researchers find that those modern-day hunter-gather populations who base their diets on meat, such as the Inuits (Eskimos), suffer from heart disease and other forms of atherosclerosis, and those modern-day hunter-gathers who base their diets on plant foods (starches) are free of these diseases. Osteoporosis, from their high animal food-based diets, is also epidemic among meat and fish consuming hunter-gathers, specifically the Inuits.
No evidence presented – his link goes to a letter that has no abstract, which in turn leads to the study I linked above. In any case, it appears that Eskimos never developed heart disease or cancer until civilization and its foods arrived. Furthermore, vegetarians in India have a much higher rate of heart disease than non-vegetarians, based on studies never quoted by Dr. McDougall.
Furthermore, according to Dr. Cordain, a diet very high in animal protein foods would cause a person to become seriously ill with nausea, vomiting, diarrhea, and eventually death from protein toxicity (also known as “rabbit starvation”). (p 105). For most people the dietary ceiling for protein is 200 to 300 grams a day or about 30 to 40 percent of the normal daily calorie intake. The Paleo Diet is as high as 35% protein. (p 24) Contradicting his warnings, Dr. Cordain consistently and frequently emphasizes that “Protein is the dieter’s friend.” (p 48).
McDougall is totally arguing in bad faith here. Just beacuse too much protein can be unhealthy, that doesn’t even slightly imply that a no-meat diet is healthy, or that a diet higher in protein than the ones Westerners currently eat couldn’t be healthy. Does McDougall think that his readers are stupid?
Eating animal-derived foods causes our most common diseases for many well-established reasons, including the indisputable facts that they contain no dietary fiber, are filthy with disease-causing microbes (including mad cow prions, and E. coli and salmonella bacteria), and contain the highest levels of poisonous environmental chemicals found in the food chain. Remember, disease-causing red meats, poultry, fish, and eggs make up 55% of the Paleo Diet.
Dietary fiber has been studied and found wanting. Microbes on meat are a concern, but so are microbes on vegetables, and in any case they are a product of modern agricultural practices, not inherent in meat. I would guess that hunter-gatherers rarely got food poisoning or dysentery – these come from humans and human interventions.
All large populations of trim, healthy people, throughout verifiable human history, have obtained the bulk of their calories from starch. Examples of once-thriving people include Japanese, Chinese, and other Asians eating sweet potatoes, buckwheat, and/or rice; Incas in South America eating potatoes; Mayans and Aztecs in Central America eating corn; and Egyptians in the Middle East eating wheat. There have been only a few small isolated populations of primitive people, such as the Arctic Eskimos, living at the extremes of the environment, who have eaten otherwise.
Therefore, scientific documentation of what people have eaten over the past thirteen thousand years convincingly supports that starch, not animals, is the traditional diet of people.
Uh, does McDougall understand what “paleolithic” or “prehistoric” mean? Apparently not, because they do NOT refer to the last 13,000 years. And he presents no data on how healthy the peoples he cited were. Sure, they didn’t suffer from obesity, but neither did we until very recently, and to blame that on meat is absurd.
The longest living populations on planet Earth today live on starch-based (low-animal food) diets. These include people from Okinawa, Japan; Sardinia, Italy; Nicoya, Costa Rica; Ikaria, Greece; and the Seventh Day Adventists in Loma Linda, California, who live in what are called the “Blue Zones.”
Mormons live longer than Seventh Day Adventists, and Mormons eat meat, the key being that neither group smokes or drinks – though the not drinking might be a disadvantage. As for the others, none are vegetarians, and they all live lives close to family and community and are religious, some confounding factors McDougall might want to consider.
According to Dr. Cordain, “The Agriculture Revolution changed the world and allowed civilizations—cities, culture, technological and medical achievements, and scientific knowledge—to develop.” (p 43) In other words, if people had remained on a diet of mostly animal foods (assuming our ancestors actually did), we would still be living in the Stone Age. Fortunately, the Agriculture Revolution, with the efficient production of grains, legumes, and potatoes—the very foods forbidden by the Paleo Diet—allowed us to become civilized.
Dr. Cordain finishes his 2011 revision of his national best-selling book The Paleo Diet by warning, “Without them (starches, like wheat, rice, corn, and potatoes), the world could probably support one-tenth or less of our present population…” (p 215) Choose 10 close friends and family members. Which nine should die so that the Paleo people can have their way? There is a better way and that is The Starch Solution.
Here I don’t dispute McDougall. Civilization brought great benefits, but with it came ill health. As for the number of people that a starchy diet can support, I personally don’t plan to compromise my health so that people in the Third World or elsewhere can have ten kids each. That’s their problem.