Robb Wolf has another post up complaining about paleo bashing. This time it is about this article in Scientific American: How to Really Eat Like a Hunter-Gatherer: Why the Paleo Diet Is Half-Baked. Such articles are written because:
People, particularly folks in the academic scene, seem to really have their britches bunched over biochemists, MD’s and others using this evolutionary biology concept to look at nutrition and health.Yeah that's it. The article begins with:
image linkMeet Grok. According to his online profile, he is a tall, lean, ripped and agile 30-year-old. By every measure, Grok is in superb health: low blood pressure; no inflammation; ideal levels of insulin, glucose, cholesterol and triglycerides. He and his family eat really healthy, too. They gather wild seeds, grasses, and nuts; seasonal vegetables; roots and berries. They hunt and fish their own meat. Between foraging, building sturdy shelters from natural materials, collecting firewood and fending off dangerous predators far larger than himself, Grok's life is strenuous, perilous and physically demanding. Yet, somehow, he is a stress-free dude who always manages to get enough sleep and finds the time to enjoy moments of tranquility beside gurgling creeks. He is perfectly suited to his environment in every way. He is totally Zen.
Ostensibly, Grok is "a rather typical hunter–gatherer" living before the dawn of agriculture—an "official primal prototype."
The article is describing the cartoonish Paleo™ and mocking it. Wasn't it the sage Jimmy Moore who said we need to ditch that schtick? Someday someone is going to have to explain to me how eating lean meats and non-starchy veggies and a heckuvalot of supplements is applying evolutionary biology to nutrition and health. Or is that fatty meats, chocolate and buttery coffee? How can Robb Wolf or any of these paleo types be SO sure of their version of paleo? The incredible degree of defensiveness when someone even asks for clarification is telling, and the various purveyors of what I call Paleo™ can't even seem to agree amongst themselves about it. The gist of the article is that Paleo™ is not so much defined these days by what folks eat, but rather what they don't because supposedly these foods were not part of the human diet before the advent of agriculture .... this despite ample evidence of consumption of grains and legumes while the acquiesced to dairy is basically impossible before domestication of animals, and would have been limited to whole milk from mammary glands of lactating prey. I agree wholeheartedly with this from the article:
How do we reconcile the Inuit diet—mostly the flesh of sea mammals—with the more varied plant and land animal diet of the Hadza or !Kung? Chucking the many different hunter–gather diets into a blender to come up with some kind of quintessential smoothie is a little ridiculous. "Too often modern health problems are portrayed as the result of eating 'bad' foods that are departures from the natural human diet…This is a fundamentally flawed approach to assessing human nutritional needs," Leonard wrote. "Our species was not designed to subsist on a single, optimal diet. What is remarkable about human beings is the extraordinary variety of what we eat. We have been able to thrive in almost every ecosystem on the Earth, consuming diets ranging from almost all animal foods among populations of the Arctic to primarily tubers and cereal grains among populations in the high Andes.”
And yet, that's really what Cordain and company do. In a rebuttal written by Loren Cordain he writes:
Unfortunately, a number of fundamental limitations exist with δ13C analysis to evaluate diet. δ13C measurements cannot determine the exact species of either C3 or C4 plants that were consumed, but more importantly δ13C values cannot distinguish if the C3 or C4 signatures originated from the direct consumption of plants or from the indirect consumption of animals that consumed these plants.
This is an interesting statement as it admits uncertainty. The Paleo Diet he developed and trademarked was developed from looking at hunter-gatherer diets in relatively modern times. So we don't know that our ancestors ate this diet to ANY degree of certainty. If we cannot be certain of the origin of the isotope in the human diet -- be it direct from vegetation or indirect from animals consuming that vegetation -- how can we be certain of the animal content of the diet? You can't have it both ways.
In Hominins living on the sedge, Nathaniel Dominy, Anthropologist at Dartmouth , whom Cordain might include amongst colleagues, writes (of another paper written in 2012 by the same anthropologists responsible for the current works):
The magnitude of C enrichment, which, among australopithecines, is eclipsed only by Paranthropus boisei (6), suggests that the carbon in their diet was derived mainly from C plants rather than the tissues of C grazing animals (5). This inference led the authors to focus on sedges, a graminoid plant that is perhaps more promising than grass as a food source for hominins. Indeed, the thickly enameled, low-cusped (bunodont) teeth of A. bahrelghazali and P. boisei would appear to be functionally incompatible with a diet of grass blades (7). Could sedges, then, bring consilience to the C conundrum?
So I agree with Robb Wolf. Before going off on something it is a good idea to read the literature, and it's a good idea to broaden your resources past those so often cited by the Paleo™ community and such.
Robb quotes from a comment left by Kim Hill, PhD on that Scientific American article. His CV is here and here's a synopsis from the first link:
My theoretical interests cover the evolutionary ecology of human behavior, and the evolutionary history of later hominins. I have worked on foraging theory, time allocation problems, food sharing, life history theory, parental investment, divisions of labor, cognition and social status, culture and the emergence of hyper-cooperative behavior. My applied work has included conservation biology and resource management, land rights issues, health issues, and the ethics of anthropological research.
I think it is fair to say that his focus is more of a cultural one than one of discerning the diet of early hominims. What of his work with the Ache? You can find that HERE.
Systematic recording of dietary intake while living in the forest entirely off wild foods suggests that about 80% of the energy in the diet comes from meat, 10% from palm starch and hearts, 10% from insect larva and honey, and 1% from fruits.
This is very interesting because this bears zero resemblance to any diet I've seen in Paleo™ or in the studies on the paleolithic diet that are fruit-heavy. I wonder if palm starch is a safe one, but PHD is the only diet that includes starch. The Paleoista, who introduced paleo foods alongside Cordain on the Dr. Oz show, says that only endurance athletes should consume starch. And eighty percent calories from meat??? Even Eaton/Konner/Cordain/Lindeberg and all the rest don't put it near that high. Actually, this paper by Hill discusses the seasonal variation and puts meat at 47-77% while honey ranged from 0.4-44% of calories (mean calories ~3700/day). What kind of meat? Why armadillo, lizard, deer and monkey. Impossible to find the nutritional info on a whole armadillo, but the meat is quite low fat: 1 oz cooked boneless meat contains just over 1 gram of fat and 8 grams of protein, and the fat is almost half (47%) MUFA and only about 36% SF and 18% PUFA. It is difficult to ascertain the fat content of the diet from the paper I linked, but it, too, varied seasonally and protein intake is likely very high. (I'm efforting other citations and will edit in links if I'm successful, didn't want to hold up the post for them however.)
In any case, here is part of the comment Hill made on the article with Robb's emphasis in bold and mine in bold red:
But the point is that if Hunter-gatherers are lean, and fit (they look much more like serious athletes than do modern people), why? If not their diet and exercise regime, then what does make them lean and fit compared to modern people? Logic suggests that diet is part of the solution (excercise seems downplayed by everyone). So the discussion here should be focused on what we can learn from hunter-gatherers to improve our own health. How do “paleofantasy” critiques contribute to that discussion? I'm not sure, I haven't read the book.
Hill discusses his and his wife's fitness as well and he speaks of the Ache of Paraguay from much experience living among them. Firstly, I'm unsure that modern Americans are the only yardstick of health against which to compare these hunter-gatherers, but scan through the page and see if you don't see what I do. Quite an array of body types and outward appearances of health. I see emaciated and muscled, lean and abdominally obese. The toothed and the toothless.
Hill, himself, describes the activity level of the Ache as one with "extremely high exercise loads" yet later in the comment acquiesces that exercise is downplayed. The thing about all of these cultures is that you can't just take dietary lessons without environmental context -- at least Kruse got that much correct (to some degree anyway).
But I suspect Robb was heartened by Hill's kumbaya and doesn't really care much what the facts are. If the average American were to try to reproduce the Ache diet, they likely couldn't, but replacing armadillo with pork, lizard with livers and monkey with mutton isn't going to cut it. Let alone with the (bordering if not outright eating disordered) fructophobia in the paleo community, and the aversion to starch, what would a Paleo™ Ache-style even look like?
Interestingly, Hill commits the sin Robb Wolf accuses everyone else of -- he hasn't even read Zuk's book, so how can he really comment? One would think that someone like Hill would be more offended by the modern manifestations of some so-called paleolithic diet and the traveling circus it seems determined to be. Which is not to even mention the rampant supplement pushing, laxative abuse, cleanses, fermented cod liver oil worship and aversion for anything modern medicine has to offer. At least the ladies of Paleo are more forthcoming fessing up:
The lady Paleos get understandably defensive when asked about the backlash. They protest that the Paleo diet is just a guideline; it's not supposed to be taken too literally. "I'm not hunting for my food," Sanfilippo says. "We're not trying to live like we're in the Paleolithic era. There's modern technology. But we're just trying to revert to a diet through which our bodies can live in their best and healthiest forms."
Perhaps that's why the tribeswomen are inching away from the term "Paleo." It's just a marketing tool, Sanfilippo admits: "The only reason that I call what I'm doing the 'Paleo diet' is that it helps people understand what I'm teaching them." Fragoso echoes the sentiment: "Honestly, if this wasn't my career, I wouldn't call it anything," she says. "But it's also good that there's a name for it because it helps spread the word." (She suggests renaming it the "Real Food diet.")
"It's awesome that we don't have identical genes to our ancestors," Fragoso says. "I throw my hands up in the air and say, 'Whatever.' We're not cavemen. That's true. I don't care to live like one."
At this point to even use Paleo™ doesn't even equate with a paleolithic diet and eating paleo is not practicing evolutionary medicine. Sorry. According to Robb, it's not the stereotypical strawmen those in the mainstream who have taken note of the diet portray. I just wonder where they get these crazy ideas from. Meanwhile, I contend we don't need to go much further back than my childhood to find the answers to how we can improve our health through diet.