Paleolithic Diet Questions

This is an open "question post" to my readers, many of whom I'm aware are followers of Paleo-derived WOE's.   I'm particularly addressing those that advocate limiting protein and eating a very high fat  (60-80%) very low carb (close to zero) diet.

What research am I missing that counters the work of Eaton?  Links to his works that I've blogged on HERE and HERE.  The first work was even referenced in The New Atkins to indicate that a high fat diet is what we evolved to eat.   Seems Eaton mostly points to a diet a little higher in carbs (~40%) and protein (~35%) and much lower in fat (~25% is the highest estimate) than most of the paleo/primal plans I've seen.  I don't see much reason to question this work.  

Where does the very high fat come from?  What am I missing?  


Anonymous said…
i eat around 65-70% fat, 15 carb, 15-20 protein. too much protein gives me acne/dry skin/eye circles, and not enough fat leaves me feeling hormonally outta whack.

where does the fat come from....yummmmmm...
coconut milk
coconut butter
blanched nuts
full fat fage(semipaleo i know)

its less about quantity more about quality and nutrient density. i am not a big fan of muscle meat and eat a crapload of various organs all cooked in fats

i do not think excess protein is all its whacked out to be as studies soon to come out show it IS in fact related to CVD, not to mention the overload amino acid burden overpowering others like tryptophan which have a hard enough time crossing the BBB etc etc.
CPM said…
Matt Metzgar posted a similar question a while back, but there was not really a Paleolithic argument offered:

I can't speak for anyone else, but I suspect the rationale is due to the influence of Taubes, Eades, and other low-carbers among Paleo bloggers. I believe Kurt at PaNu said that he had an epiphany listening to Taubes. Peter at Hyperlipid seems to be pretty influential, and he follows Kwasniewski's Optimal Diet (high fat, low carb, limited protein).

"Paleo" seems to be in the eye of the beholder, but I think if one were to define it as "avoiding certain key Neolithic foods" like trans fats, seed oils, grains, and legumes, then one could still claim to be Paleo no matter what the macronutrient profiles are. Again though, everybody seems to have their own definition of Paleo.
Jeremy said…
I would read the Perfect Health Diet eBook by Paul Jaminet, who gives extensive breakdowns of research on each macronutrient. The Perfect Health Diet is a paleo diet in that it advocates reducing fructose, grains, legumes and vegetable oils. It is also is a high fat diet by % calories.

Pages 8-102 of the eBook are about optimizing macronutrients, so I cannot do the book justice in a blog comment. But the basic idea is he presents evidence that polyunsaturated fats, carbohydrates and protein promote disease or reduce longevity when eaten as a higher percentage of calories than he recommends. He suggest all saturated fats and monounsaturated fats are safe fats.

I would be happy to buy you a copy of the book if funding is an issue, because I am following his advice and having an informed skeptic read and respond to it would be beneficial to me.

Melchior Meijer said…
Hi Carb Sane,

You might be interested in this analysis by Kuiper, Muskiet et al, posted by the magnificent O'Primitivo:

By the way, you and Lynn are creating a healthy dose of cognitive dissonance ;-).
Paul Jaminet said…
Hi CarbSane,

Just noticed this thread. If you're interested in our book, send me an email with your address and I'll send you a free copy. I would be delighted to get a critical review.

Re your question, since the only published papers are from Eaton-Cordain, including the latest one, there's a risk of investigator bias. Especially since we only know the animals eaten, not what parts were eaten. The original Eaton paper was obviously wrong because it assumed whole carcass eating, and every known hunter-gatherer tribe preferentially eats fat and discards protein. We know Paleolithic bands went to great effort to crack bones to get marrow, so very likely they did the same. Every modern population on earth eats protein to 15% calories, and it seems likely that Paleolithic peoples did the same if they could.

The Eaton-Cordain prejudice has always been toward high protein, lean meats, low fat, anti-saturated-fat. Also Cordain has been anti-starch, another error. Cumulatively these force them into advocating a high-protein diet.

In short, I don't believe Paleolithic peoples would have voluntarily eaten such a high protein low fat diet unless Malthusian population pressures forced them into it.

Best, Paul
Todd Hargrove said…
I glad you are asking this question.

One possible answer is that back in the day the menu looked different. I think the leading theory explaining the disappearance of the mega fauna is that they were hunted down by humans. When you kill a mastodon you're going to eat as much fat as you want. And you'll take the cuts that taste like rib-eye not chicken breast. Of course this is just speculation.

What I find more convincing is Paul's excellent analysis in his book that shows that the body appears to be designed for consuming less protein and carbs than Cordain recommends. At the level of carbs recommended by Cordain, the liver will convert some carbs to fat, right? Why not just eat fat in the first place and spare the cost of high interim blood sugar and extra work for the liver? Same with protein, why eat more than you can use and create extra work for the body to convert it to something more useful? Why not just eat the amounts of carbs and protein that the body will actually use? Mother's milk appears to be a perfect food in this respect.
Colby said…
I know you are looking for their justification but I have a mini rant. I am currently torn between the benefits and communities that the paleo movements are bringing and some of the misinformation they are generating. Some of the bloggers are clearly very intelligent but some are just taking advantage of a buzz word for $.

"As the few detailed ethnographic data show, the diet composition of the individual hunter-gatherer groups varied considerably and ranged from a nearly pure animal-based diet to a diet dominated by plants. All in all the eating behaviour of prehistoric humans was, like that of their pleistocene ancestors, very flexible. Except for focussing on an energy and nutrient-rich diet there was neither specialization in certain foods, nor a typical plant-animal ratio nor a defined macronutrient distribution. Correspondingly, it is impossible to justify details given by representatives of evolutionary medicine on "the Paleolithic diet" empirically. "

I think searching for an optimal "paleo" diet is unnecessary- the paleo principles reflect what a "healthy" diet should anyway, that is focusing on whole foods. Do we need to label this as "paleo" "primal" or "caveman"? No. Ironically even though paleo proponents often criticize nutritional reductionism, they frequently target specific nutrients (like fructose) at which moderate amounts the evidence so far suggests does not hurt us metabolically.

There is clear evidence that we HAVE evolved significantly since agriculture was introduced contrary to what Eaton, Cordain, etc have stated (we didn't have the genomic revolution when their theories were established) so demonizing grains or other foods completely for all people is premature. Before concrete conclusions can be made more research must be completed.
CarbSane said…
WOW!!! Thanks everyone for the comments and input. Welcome to my blog CPM, Paul, Melchior and Todd thanks for reading and commenting.

@Mal: I'll be interested in these studies you are eluding to. Also interested about the eye circles and breakouts. I get these sometimes more prominently than others (I'm a good deal older than you but ...). Haven't correlated that to protein though. I didn't have a break out to speak of for two years doing VLC most days and broke out quite a bit when I first tried IF eating high fat. Go figure??

@CPM: Thanks for the link to Matt's post. I tend to agree with a lot of what is said there. I would agree with your "hunch" about the influence of Taubes and Eades, etc. I also believe once LC'ers discovered gluconeogenesis and protein's insulin stimulating role, many see fat as the only non-fattening macro. Also seems Atkins has gone the way of "high fat" to avoid the stigma of "high protein". Many in the whole paleo/primal circles find their way to that WOE through an LC Diet like Atkins or Protein Power.

@Jeremy: One way or the other I plan to read Paul's book and will share my thoughts. Really looking forward to that. I looked at the general dietary recs on his site, and on first look I'm intrigued by the somewhat different stance on starches. I've always felt that starch had to be available to our ancestors, and is certainly a big part of enough examples of cultures exhibiting longevity. To that end, one of my major quibbles with Mark Sisson's interpretation of what's appropriate would be his shunning of starch. Protein is a little low for me -- I think I would starve and/or eat too much fat to compensate and gain. Looking forward to his take.

@Melchior: Thanks for that link! It seems a major point of contention is just what parts of the animal paleo dude ate. Many claim that modern cultivated fruits and veggies bear little resemblance to those available to paleo dude. I would say the same holds true for the beef and beef fat (even grass fed) that seems to be so prevalently consumed. At the very least, folks need to be eating organ meats, brains, tripe and chiterlins. Yuck. Anyone who can do that after my former line of work is a better person than I!!
CarbSane said…
@Paul: Thanks for that generous offer! Email on the way shortly. Yes, I've noticed the "circular referencing" in a lot of the publications, and I would agree there may well be a fair amount of investigator bias injected there. Cordain's approach in his diet is to try to use modern foods to reproduce macronutrient composition of ancestral diet. In many ways I think this has potential to be better than eating certain modern foods (beef) simply because our ancestors were "meat eaters". Looking forward to your thoughts on protein and why it is limited. *Sigh* I do better on higher protein, so I guess I'll just have to die a few years sooner. ?) I guess when I look at fat consumption in the high fat diets I don't see getting above 55-55% w/o added fats. I have a hard time believing that life was easy enough that protein was left to waste since protein can and does feed nicely into Krebs for energy. Things like olive oil and coconut oil while components of paleo would not be forms available to them. The other thing I'm interested in is your take on PUFA's and I look forward to discussing this with you. I do have a hard time seeing how the O6:O3 ratio was 1-2:1 except in the cold water fish-based cultures.

@Todd: Hmmmm. I don't know about you, but I would rather eat steak tartar than a bunch of fat! Cooked? Yeah, gimme prime rib, but raw fat uggh. Perhaps that's different for the organ meats and brains, but I'll never find that one out.

As for consuming what's useful, on the carb intake, a couple of my blog posts related to this can be found here and here. For a very long time I felt that protein was a poor energy source -- that it would have to be turned to glucose (requiring caloric expenditure of fats) to be used for energy. Not so, as I blogged on in Protein for Energy.

Don't get me started on milk ;) I contend that we humans are a creepy sort when you really think about this one. Milk is infant food, infants having very specific nutritional needs for rapid brain development, etc. What adult mammal consumes the infant food of another species? IMO, eggs are quite a perfect food too, but I doubt they were eaten several at a time daily. Pass the cheese omelet please ;)

@Colby: Thanks for that rant! I agree with much of what you have to say. And I would say that even IF we have not evolved one iota, there's no reason to believe a paleolithic diet was ultimately healthier, it was what they had available. And evidence abounds to a high degree of adaptability. I also agree on the demonization of grains and wheat particularly in the context of obesity. All my elementary school classmates ate sandwiches on Wonder bread for lunch! Fructose ... heck, I've even found evidence that fructose can be protective in normal doses. It is idiotic to extrapolate the deleterious effects of 2L+ a day Coke drinking habits to any fructose consumption in fruits. My bottom line is not to try to mimic that diet per se. Firstly, I'm not that disciplined and you can tear my cheese away from my cold dead hand. But I am interested in the justifications for certain dietary recommendations. For me? Whole foods as much as possible. In the end, if I feel good I know I'm eating well for my body. My body tells me when I'm not!
Todd Hargrove said…

Regarding the raw fat, I agree, not so appetizing, but Richard Wrangham has some compelling arguments in his book Catching Fire that mastodons would have been cooked not eaten raw. He claims that cooking was invented far earlier than is often assumed, and that it was the key step that allowed us get rid of our big guts and get big brains instead. The cooking basically does some of the job of digestion, freeing energy to get a bigger brain.

Regarding milk, my point is not that its a perfect food for adults, but that as a perfect food for infants, we can look to its macronutrient ratios as guidance for the perfect macronutrient ratio for adults. Once you correct for brain size, milk is low to moderate carb for a baby. (I got this argument from Paul's book and hope I stated it correctly.)

Re the protein for energy, thanks for the links, I will have a look.
CarbSane said…

My first thoughts regarding Catching Fire (haven't read it) were that we have a chicken v. egg dilema on our hands. Did pea-brained humans invent cooking to consume the fat to develop higher functioning brains?

I'm not sure we can look at milk -- infant food -- as a model for the perfect food for the adults or even post-weaning-aged members of any species. I would dare say that the macronutrient composition of the adult diet of wild animals differs substantially from that of mother's milk. For one thing, the fat content (MCT's for example) differs significantly from that in meats, etc. Carb is mostly lactose as opposed to glucose/fructose/sucrose and starch in plant foods. Infants have way different needs.

Oddly enough, I've learned that high protein in formulas is linked to obesity later in life, while higher protein diets have been demonstrated to lead to spontaneous decrease in caloric intake and weight loss in adults.
Anonymous said…
Evolution selects for reproductive fitness, not longevity or health in old age. Evolution might well causes us to prefer foods which generate good health through age 50, then cause us to die soon thereafter so as to avoid competing with our children and grandchildren for scarce resources. So the ancestral diet, the one we naturally prefer, might not be the diet that causes us to live to age 100 and be in perfect health until that ripe old age. What I want may not be what Mother Nature wants. Perhaps I have to resist Mother Nature to get what I want.
emu said…
Having done the Paleo diet and currently being somewhat primal, I'm interested in this discussion. Always when reading the books on Paleo/Primal the nagging question in the back of my mind was, is this diet really appropriate for longevity? Sure, we evolved to eat it, but as @revelo says, perhaps it helped us live to 50 and that it's. I believe that Paleo supporters would say that studies of modern hunter gatherers shows them eating similar diets and living long lives. I'm curious what people think of this argument?
CarbSane said…
Welcome emu! I've been a bit deluged with comments lately with scarce time to respond in timely fashion.

In line with what some of us have been discussing re: diabetes, I would add that it seems that humans may well not have evolved since Paleo days, but different groups of humans sure have genetically adapted through the centuries to varied diets, but the predominance of which are higher in carbs and lower in fat, and even if higher fat, different fats (e.g. tropical oils).

So some experience improvements cutting dairy, but others gain no benefit. It seems the more adapted to carbs e.g. Japanese & traditional Pima, the more vulnerable one is to obesity and diabetes when exposed to more fat in the diet. Unfortunately the high fat diet they are exposed to is SAD or SAD-like Western diet, not low carbohydrate so we have no way to really know.

It seems to me that those of us with more "pure" lineages would probably due best to eat a traditional diet of our neolithic ancestors. What of the conundrum for the "mutts"? Well, in one sense perhaps they can handle the crap a little better as they are less sensitive to whatever it is that sets off highly adapted genes. But, OTOH, they could be susceptible to everything.