The very first time I ever heard about the paleo diet was one and half years ago. Now it’s all over the traditional media, blogosphere, and twitter. I just finished reading a long article in the Atlantic magazine, This Is Your Brain on Gluten.
The author, James Hamblin, builds the article around a virtual dialogue between two MDs. David Perlmutter is the author of Grain Brain: The surprising truth about wheat, carbs, and sugar; your brain’s silent killers. I haven’t read the book, so here’s a quick summary from the Atlantic article:
Over the last 40 years, people have become addicted to gluten, Perlmutter’s narrative goes. In combination with carbs, gluten’s influence on our diets explains why we get dementia—and every other common neurologic problem. “Inflammation is the cornerstone of Alzheimer’s disease and Parkinson’s, multiple sclerosis — all of the neurodegenerative diseases are really predicated on inflammation. Who knew?”Sign up for our newsletters
This sounds pretty close to the message I’ve been getting from Michael Rose, Paul Jaminet, and John Durant—my three Paleo gurus (although there are some variations in their views, the overlap between their views on the right diet is over 90 percent; good enough for me).
The second MD in the debate is David Katz. He seems to be pushing the standard line, although it has been eroding recently (in particular, on cholesterol targets and the need for statins). He also says “There actually is an argument to give the Paleo diet serious consideration.” But mostly he disagrees with Perlmutter. As Hamblin reports,
Perlmutter has estimated that the Stone Age diet was 75 percent fat, a claim Katz finds “wildly preposterous.” Anthropological research, he pointed out the work of Loren Cordain, suggests that in the age before cooking oil, humans ate mostly plants with a scattering of seeds and nuts. “Virtually nothing in the natural world is that concentrated of a fat source, except maybe for the brain. Maybe if they just ate the brains of animals? They didn’t have oil. They only started adding oil to the diet after the Dawn of Agriculture. What the hell could they possibly have eaten that would be that fatty?'”
Now the 75 percent number is too high, I agree. But Katz rebuttal is ridiculous. “Humans ate mostly plants with a scattering of seeds and nuts”??? Aren’t seeds and nuts also plants? And what about meat (including seafood)? Evidence for meat eating in the Paleolithic era is extremely robust. Furthermore, we are critically dependent on getting our Omega-3 fats, and main sources of getting this essential nutrient are grass-fed ruminants (e.g., beef and lamb) and seafood.
One underappreciated source of fat is bone marrow (see my blog on this). Katz seems to be pretty clueless about the diet of our ancestors pre-agriculture (at least judging from the way his views are portrayed in the article).
James Hamblin also seems to be pretty clueless. In the end he simply chose the middle ground between Perlmutter and Katz. But, as the Texan saying goes, “There’s nothing in the middle of the road but yellow stripes and dead armadillos.”
One part of the article that amused me was the discussion of the scientific method. The article essentially accuses Perlmutter of only using results when they suit his preconceived ideas. Perhaps. But the definition that Katz gives of the scientific method is hilarious:
“You’re only being a good scientist,” Katz said, “if you say, ‘I’m going to try to read the literature in as unbiased a manner as I possibly can, see where it leads me, and then offer the advice that I have based on that view from an altitude.’”
You owe your readers some pointed elaboration on your closing “Puh-leeze!”
Katz is not providing a definition of the scientific method. In his words “You’re only being a good scientist” if you take that unbiased approach.
His description sounds like a decent, if casual, description of having a scientific mindset. The major challenge we face is being truly unbiased and empirical rather than confirmation seeking. If you’re not doing primary research then you must be unbiased in your search for, understanding of, and consideration of the research that exists.
What approach do you advise that is more scientific in spirit and practice?
Katz is simply lamenting the fact that so many charlatans and cranks out there try to give the pretense of scientific understanding when in fact they’re cherry picking and distorting. They’re data mining, demonizing, and manipulating.
Do you think it is acceptable to deliberately frame an issue and seek supporting evidence in a manner that leads to a pre-existing conclusion?
The scientific approach is to seek DISCONFIRMING evidence. Scientists try to DISPROVE hypotheses and theories. They seek new and novel ways of testing existing notions always open to something that could contradict existing knowledge.
The formal scientific method means advancing explicit alternative hypotheses, based on mechanisms, and collecting data to empirically test theories. While I am not defending Perlmutter (if it’s true that he only uses evidence that fits his theory), being unbiased is a very small part of the scientific method.
Perlmutter is utterly preposterous–far beyond the wildest real anthropologist. Cordain is a top authority and basically right. What we find from actually looking at data is a wide range of diets, but ancient humans probably did live on seeds, nuts, fruits and small animals, with occasional large ones. Lots of fish if there was water around, and early humans couldn’t go far from water. There would have been a very wide variety in dependence on plant materials vs meat and fish. Bone marrow is not abundant enough to be a very significant nutrient source. Remember early humans didn’t have elaborate hunting technology, though they got pretty good spears and so on by 3-400,000 years ago. They would have sought out the most nutrients per hour invested–whatever provided that without too much effort. The various paleo diets are all pretty silly. Ethnographically known hunter-gatherers lived on meat in the high Arctic, but otherwise on plant materials + fish if on a coast or major river.
As I discuss in my blog on bone marrow, the hypothesis is that early humans did not kill their prey, but scavenged other predators’ kills. Evidence for seafood consumption is also very anundant.
Sigh. And of course humans had stopped evolving from paleo times. No change whatsoever. None. Nada.
Our metabolism is exactly the same as 50000 years ago and identical for all human populations. Your race and origins don’t matter. All this stuff about lactose tolerance, alcohol intolerance, high altitude adjustments happens in another universe.
It helped humans to reproduce more. Doesn’t mean that it helped people to live well in old age. I doubt that Alzheimer’s was terribly significant when it came down to evolutionary fitness.
That’s a nice quip, but I fail to see your logic. You seem to be saying that evolution (during the past 50,000 years and specifically changes in metabolism and dietary-related development) would not have resulted in better old age quality of life. You’re implying that evolution wouldn’t address old age quality of life (since few lived to be old and evolution is based on reproductive success). Fair enough.
So then tell us why an even more ancient diet would be better at enhancing old age quality of life? Would not the more ancient diets simply reflect the need for survival / reproduction?
Simply put, evolution had a much longer time to “detoxify” the ancient diet (if there were indeed toxins there). There’s some correlation between traits that help old people live happy lives and evolutionary fitness (as social animals, knowledge does get passed down). It’s just not a very big one.
Here, since I don’t want to waste time typing, I’ll just link to Turchin’s original article that mostly said all this:
In some other article, he noted that plants evolved fruits _specifically_ to be eaten. They evolved seeds specifically _not_ to be eaten. This is especially important for plants as they can’t run, so they needed other defense mechanisms (like poisons or hard shells). So, fruit is definitely safe and good, meat (in responsible quantities) is likely safe, nuts (with their hard shell as a defense & thus less need for poisons) probably are safe (plus humans have been eating them for a long long time), and grains definitely are not.
Thanks, Richard. As I note in my response to lurker, I discuss these evolutionary issues in my first blog on the paleo diet.
What it boils down to is that for me, with my very shallow neolithic ancestry (1-1.5 thousand years at most) and being past 55 years old, the novel neolithic diet is a poison. Which I have experimentally demonstrated for myself over the last 1.5 years (see my posts with periodic updates on how I am doing – search for ‘diet’).
Perlmutter may not be a credible source for Paleo diet, but his version is much closer to the truth than Katz’s.
Read my first blog on paleo diet:
(this is in response to lurker)
Is it really feasible for much of the world to support itself on a paleo diet? Don’t you get more calories per acre with starches, oils and sugars from plants? In traditional peasant societies, the peasants ate mostly starch from grains and roots, along with not-enough protein, fat, and vitamins from other plants, and limited animal protein, while the elite consumed much more meat, and were probably closer to paleo. I wonder if the inegalitarian society of the future is one in which well-educated professionals eat some version of a paleo/foodie diet, while the underemployed poor get ill nourished and fat from a diet of cheap starch, corn oil, and corn syrup, served in large economy-sized portions, with lots of fake cheese and fake grape flavoring.
“Is it really feasible for much of the world to support itself on a paleo diet?”
Nope. Unless we start eating insects in vast quantities (probably a decent portion of the real caveman diet, BTW).
And yes, the world is unequal.
I think you’ve made yourself look a bit silly, and I would have expected better of you after reading some of your earlier material. This article has instigated a lot of doubt about hte rigor of your thought.
To be equally pedantic as your “Aren’t seeds and nuts also plants?” Um, not really – no more than to say eggs are birds. From a nutritional standpoint, it’s completely different to eat a developed live plant as opposed to a seed or not (mix of fat, fiber, vitamins, etc. being completely different).
Further, our paleo ancestors, even if they ate an all-meat diet (disputed), would eat far less fat than the average Westerner does, simply because meat as most Westerners know it comes from mostly sedentary animals, so it has more fat than any wild animals do. Think of venison vs. beef. Dairy also contributes a big chunk of the fat in our diet, and it would not have been available before domesticating animals. Marrow is fatty yes, but it’s also one of the most desirable things for large predators to take, so if we were scavenging food it would probably be mostly gone. Further it is a minor part of the total mass of the animal, so getting enough calories just from marrow would require a rather large number of animals to be killed on a daily basis, and would require leaving behind an extravagant amount of food.
As for seafood, one of the reasons it’s considered a healthy food as opposed to meat is because it has a relatively high protein and low fat content (as well as having a different mix of fatty oils)
A couple of things to add to your description of lean meat in wild animals.
1) I remember reading about the amount of meat men ate during the Lewis and Clark Expedition. It was incredible – up to nine pounds of meat per man per day. Presumably this was because of how lean the meat was. (*)
2) We wouldn’t expect our ancestors to have been squeamish about the “nasty bits” and they well may have gone in first for organs such as liver and brain. So that’s a bit of a counterpoint: Though the animals’ muscle meat would be lean, the question is what the total edible carcass proportions were.
* See: http://www.pbs.org/food/the-history-kitchen/what-lewis-and-clark-ate/
Excerpt: “each man consumed up to 9 pounds of meat in one day. …Bison and deer were prominent during the crossing of the Great Plains, while salmon and a starchy tuber known as wapato kept them nourished as they entered territory west of the Rocky Mountains. …. At Fort Clatsop, elk was in large supply. It was served boiled, dried and roasted for breakfast, lunch and dinner.”
I’m not sure I’d take guidance from the Lewis & Clark expedition for a typical Westerner, even one who works in a physically-intensive job. Furthermore, the nine pounds was a peak level (when game was plentiful), but there were also lean periods, so the average would be considerably less. In all cases, spending all day on rough terrain carrying equipment is far different than the typical office worker’s lifestyle, even if that person gets double the average levels of exercise in our population. Even if you adjust the total portions, I question the appropriateness and the correct nutritional balance for a 21st century lifestyle.
I question this latest fad diet, as I have the random other fads that seem to crup up a couple times a decade. It’s great for selling books, great for building up health care costs, but terrible for the people who follow through with them, especially when they read things like “nine pounds of meat a day” and follow through on that while they sit in their offices half the day and in front of the TV the rest of the day.
Well, paleo doesn’t say that you have to eat 4000 calories a day. In fact, the hard-core paleo guys do semi-fasting.
In any case, eating fruit, nuts, and insects until you’re full (along with some other sources of protein) 5 days a week with semi-fasting the other 2 days is almost certainly better for you than the typical American diet.
It may sound like a fad, but my prediction is that it won’t be. Actually, 2014 is pushing it, I admit. It will take 2-3 more years for scientific studies to begin demonstrating conclusively the value of Paleo diet.
Certainly, I have been on it for 1.5 years now and I have no intention of switching back.
Thx for article! Also check this nice recipes http://www.paleo99diet.com
Thanks for the recipes, John. I am going to try the one for meatballs with sweet potato chips later this week. Hmm, ‘mince’ must be British for ground meat…
This brings something to mind:
I suppose the typical Irish person before the potato famine was quite paleo as well, as most people there ate nothing but potatoes (salt being the only other thing that would be in their diet); The average Irish farmer ate 10lbs of potatos a day. It actually made for a balanced nutritional diet.
The two mainstays of the Irish peasant diet were potatoes and dairy. Almost every household had a cow. Which is a good thing, as you wouldn’t be able to survive on potatoes alone. So the dairy part is not Paleo.
Oh right. Though I read that the years before the famine, the most of the milk was sold off for income.
An alternative perspective:
Bodybuilders know best. And bodybuilders know that if you want to weigh less, you eat less. They’ve known this for some time.
Fat nerds, on the other hand, don’t like to eat less. So they come up with things like Paleo… which ultimately results in them eating less.
If Peter were to restrict himself to 2,500 calories per day for the next 1.5 years while consuming a standard western diet (by composition, not quantity), his health markings would stay the same or improve. But he doesn’t have the gastronomical discipline to carry out this experiment, so it will never happen.
That said, I don’t begrudge anybody their psychological hacks. If Paleo keeps you from being a lard, have at it. But it’s just a concession to human weakness.
Also, you’re going to get old and die, slowly and messily, no matter what you eat, unless you get e.g. hit by a bus. “Health nuts are gonna feel stupid one day, lying in hospital beds, dying of nothing.” –Red Foxx