Meat based diets made us smarter | Hacker News Reader

Meat based diets made us smarter

npr.org

45 pointsbarmstrong66 comments

This title appears to be knowingly misleading. Towards the end it actually goes on to say 'And cooking is what he thinks really changed our modern body'. In fact it could just have easily been cooked starchy foods that had the biggest impact in supplying more calories. Either way it was the additional supply of calories that made the difference - not some magical ingredient of meat. I guess the diet Taliban are a ready audience for a journalist without any actual original research to report on.

It looks to me like the author was building a point about evolutionary bootstrapping of brain growth by eating meat ("but eating meat apparently made our ancestors smarter - smart enough to make better tools, which in turn led to other changes, says Aiello"). Brain growth was later accelerated when early humans gained the intelligence to cook.

From what I understand about brain development from my child's pediatrician, dietary fat is important. I don't think the calorie argument is airtight. There's more to the story than is presented here.

Anyway, the author opens with information from one source who seemed to focus on meat and later includes information from another source focusing on cooking. An editor probably read two paragraphs and wrote the headline. Nothing to get bent about.

> It looks to me like the author was building a point about evolutionary bootstrapping of brain growth by eating meat

He actually spoke to 2 separate anthropologists who had different views about our evolutionary diet and he chose to weave them into his own narrative. The second anthropologist, Richard Wrangham wrote the book "Catching Fire: How Cooking Made Us Human" and as you can see below he strongly contradicts the notion that we ate much raw meat

http://www.nytimes.com/2009/05/27/books/27garn.html?_r=1&...

Instead of writing about the differing opinions the author choses to strongly favor one view hide the fact that other is even in disagreement.

> Nothing to get bent about.

I think that deliberate twisting the of truth is something to legitimately get 'bent' about. The sad thing is the more than 50% of the people who see this will come away thinking they are basically saying 'meat makes you smarter' when neither of the views presented suggest anything of the sort.

The latter anthropologist is actually a vegetarian, so I very much doubt he believes that "meat makes you smarter." That was the part that made me really notice what the author was doing — when he smugly notes that his his source has to settle for a vegetarian meal.

Also is the supply of B vitamins in meat. Children have died on some strict vegan diets (eg, macrobiotic).

And your research comes from...?

...reading the actual article to the end.

...focusing on the facts mentioned and rather than the asides offered by the author.

Here's another reference to the part about starches

http://news.bbc.co.uk/2/hi/health/6983330.stm

Why the downvotes?

When I see the statement, "it was the additional supply of calories that made the difference - not some magical ingredient of meat", I want to see research.

And the phrase "diet Taliban" doesn't belong in this discussion.

Large-scale agriculture and cooking made us even smarter. A good pot of rice and beans will net you even more energy with less work than meat. It's also less likely to spoil and give you any number of diseases.

Have a look at "The Worst Mistake In The History Of The Human Race" by Jared Diamond http://www.environnement.ens.fr/perso/claessen/agriculture/m...

Agriculture was (is?) a disaster for our health.

Edit: I noticed that you spoke about increased energy intake and brain size, not just health.

Thanks for sharing that. What strikes me is that even given all that Jared argues, it's somewhat preposterous to call agriculture the worst mistake in the history of the human race.

Agriculture paved the road the specialization, and hence the progress, diversity, safety and richness we see in our lives today. We can argue over whether these are virtues or not, but we can't turn our heads from the Darwinian view of life. Living as a nomad, with everybody toiling just to feed the mouths doesn't scale. And, Natural Selection says any group that is able to specialize even a little bit gains strategic advantages over non-specialized groups. No wonder hunters and gatherers were driven to extinction.

Is Jared kidding us when he says that social echelons are bad? I guess, he thinks our hunter-gatherer ancestors treated everybody equally and with respect. I guess 30 seconds in front of Discovery Channel would tell him how apes live - alpha males "ruling" over females, and killing other males over food and right to reproduce. I'm quite amazed at his ability to scorn at social echelons and other malices brought upon us by agriculture while giving a silent nod to killing for food in the same breath!

I was speaking primarily about modern day and the future, not antiquity.

Though that paper makes some difficult-to-verify claims.

It might be less a result of the diet's intrinsic problems and more a result of evolutionary pressures favoring dumber people, because work is much easier, so investing in intellect wastes energy that could be spent on other things.

For more on the impact of agriculture, check out "Sex at Dawn." Fascinating stuff.

> increased energy intake and brain size

Human brains have shrunk since the establishment of agriculture. Brains are smaller now than during even the middle ages.

Cooking preceded agriculture in the development of the ancestral line to Homo sapiens by hundreds of thousands of years.

Large-scale cooking though is a more modern innovation.

Especially canning.

Actually, diseases are largely a result of agriculture. Hunter-gatherers were much healthier (and about 6 inches taller) than their farmer successors.

I'd guess that the higher population density in a farming civilization is more to blame for diseases than the food they're eating.

I believe the close proximity of animals and people (for the first time in history) is what was responsible for the new diseases.

Of course, the higher human population density means increased likelihood of contagion.

For most domestic animals, that is a possibility, but not for dogs.

https://secure.wikimedia.org/wikipedia/en/wiki/Origin_of_the...

"Archaeology has placed the earliest known domestication at potentially 30,000 BC, and with certainty at 7,000 BC....Perhaps the earliest clear evidence for this domestication is the first dog found buried together with human [sic] from 12,000 years ago in Israel."

And dogs came with many groups of hunter-gatherers in their intercontinental migrations.

There's also the transfer of diseases from some of the animals we depend on.

> Hunter-gatherers were much healthier

But probably not smarter in the way we think of intelligence. They didn't develop civilisation, agriculturalists did.

That's a convincing argument that higher population density improves collective intelligence, but says less about the individual.

Can you explain how the Mongols fit with this statement?

> They didn't develop civilisation

They didn't make very many durable stone structures. That's about all we know. The complexity and quality of their societies may have generally exceeded ours.

We do know they had transcontinental trading routes and fairly advanced astronomy, in Europe at least.

So your hypothesis is that what differentiates agriculturists and hunter-gatherers is intelligence?

That's an extremely strong statement. Do you have any proof of significant differences in human intelligence amongst populations?

Basically I'm saying you're full of shit. You should read the book "Guns, Germs, and Steel". It was written by someone who took the time to research the issue and develop some convincing arguments.

How about share some of the more convincing of those arguments?

http://en.wikipedia.org/wiki/Fundamental_attribution_error

"In social psychology, the fundamental attribution error (also known as correspondence bias or attribution effect) describes the tendency to over-value dispositional or personality-based explanations for the observed behaviors of others while under-valuing situational explanations for those behaviors."

Look for it and you see it everywhere.

Another theory:

"How much intelligence does it take to sneak up on a leaf?" - Larry Niven (The Ringworld Engineers)

Organic meat may be good in small doses. However most of the meat today is not the same as it was centuries ago. The book "The China Study" does a good job at explaining the diseases caused by meat.

If you believe Dr. Colin Campbell you might want to take a look at these articles:

http://rawfoodsos.com/2010/07/16/the-china-study-my-response...

http://www.proteinpower.com/drmike/cancer/the-china-study-vs...

They're both very well written and put some serious doubt into the validity of Campbell's conclusions.

It's not so much organic meat even, as grass fed, antibiotic free, ranged fed beef, served very fresh has the same benefit.

Things such as Vitamin C decay away in the meat with the current slaughter to serving times, and the corn diet instead of the proper grass diet lead the beef to be made up of Omega 6 instead of Omega 3 fats.

Meat itself may not be perfect, but modern factory meat is horrible. Corn Fed, Trough Locked Cows are horrible for you.

I don't eat much meat - I don't eat beef or pork at all, I eat some fish and chicken. I think too much meat is hard on your digestive tract, and the high caloric density with relatively low micronutrients makes it a bad call for me. Chicken, fish, yes. Beef, pork, other mammals, no.

BUT, the China Study book is very questionable. There's a very thorough rebuttal here:

http://www.amazon.com/review/R2JXW2AQARAXZL/ref=cm_cr_rdp_pe...

It's a very good rebuttal. I agree with a low-ish meat diet, but the China Study book (as opposed to the actual study) is riddled with errors and bad science.

You can also see one which was posted here:

"The China Study: Fact or Fallacy?" http://news.ycombinator.com/item?id=1499447

I don't want to be right yesterday, so thanks for that link. I agree that the book contains lots of promotion, but it still helped me a lot in understanding the role that nutrition has in our lives. My take home from that book is that eating a lot of processed foods and meat is harmful, and it's better to eat whole foods instead, mostly plants.

Edit: I'm not a vegetarian by the way.

> eating a lot of ... meat is harmful

As one of the links explains, the data shows almost the opposite. More meat was weakly protective.

That's funny, I specifically avoid fish (but eat other mammals) because I care more about the mercury in fish (and all aquatic meats) than I do about the non-cerebral badness of meat.

Yeah, nutrition is funny with all the conflicting advice. I did some looking into it and the rates of mercury poisoning are extraordinary low - fish-eating societies like Okinawa and Japan tend to be quite healthy and long-lived, and it takes eating an immense amount of fish to get mercury poisoning (something crazy like 5 servings/day, if memory serves). I feel pretty comfortable eating 1-3 servings of fish maybe 3-4 days per week, chicken or no meat on the other days.

> too much meat is hard on your digestive tract

That's completely crazy. Meat and fat are the easiest things to digest. There is no such thing as an allergy to meat, whereas something like a quarter of people have various allergies to grains, or various nightshade related plants.

Pretty much all plants have various toxins to prevent digestion. That's why plants in general need so much heavy processing and cooking to eat safely. You can eat a freshly killed animal raw reasonably safely. Eating a lot of raw grains or sweet potatoes could kill you.

Yes, there is such a thing as an allergy to meat (generally specific kinds of meat, just like you'll have an allergy to specific kinds of plants).

Perhaps the cooking is key, as stated in this article: http://www.sciencedaily.com/releases/1999/08/990810064914.ht...

Digesting meat is a lengthy process, which I'd have thought would still tire us.

I thought it was pretty conclusive that our digestive systems weren't suited for meat, and that's why there is so much colon cancer.

The raw foodies suggest that cooked food, triggers an immune reaction. Though you'd have thought we might have gotten used to it by now.

You'd have thought the powers that be would have figured out optimal human nutrition by now!

I think that's it's pretty obvious that our digestive systems are suited for meat, since we're completely incapable of digesting most plant matter.

Humans are incapable of metabolizing most of the foliage out there, whether or not we cook it, whereas we can draw nutrition easily from fruit, nuts, and even raw meat.

Our dentition patters are further evidence; we're dentally equipped as omnivores, but our dentition patters learn more towards carnivore than they do herbivore.

While we can eat and digest meat, that fact doesn't address the larger question of what is optimal for us to eat.

Our canine teeth are quite pathetic compared to true carnivores: 4, not very big. Compared to all our molars, side-to-side jaw motion for grinding veggies, etc. Also, compare teeth patterns of our primate relatives with us, and their diets - gorillas and chimps have much larger canine teeth, but their diets are mostly vegetarian.

Also, if we're meant to eat a lot of meat, why are our digestive tracts nothing like carnivores'? Compare length, acidity, and time to digest.

Finally, thousands of people die every year from choking on food. I don't think they're mostly choking on berries, leaves, or rice.

Predators' enlarged canine teeth are for catching and killing their prey, not for eating meat. Interestingly, the teeth that are adapted for meat eating in carnivores, their carnassials, are pretty similar in general shape to our incisors and canines. The carnivores carnassials are more jagged because of the limited room for their cutting action since the are in their cheeks. Human incisors are actually more effective at cutting meat in some ways than carnivores' teeth. And our "side-to-side" jaw motion is quite effective at cutting meat with our incisors.

And humans can choke on anything that is large enough and hard enough.

> Our canine teeth are quite pathetic compared to true carnivores: 4, not very big

You know that people can use tools, right?

Are you suggesting that we've been using tools so long that our teeth have evolved to account for this adaptation?

In other words, are you suggesting that there was a human at one time that had a more canine like mouth?

No, I'm saying that big canines are useful for killing things, not eating meat. People don't kill the way a tiger does, and probably never have. I don't see how it follows that people weren't designed to eat meat.

Is there an example of an animal you have that supports the assertion that it is hunting habit that determine the style of teeth and not diet?

I'm curious because I always thought diet was the driver in mouth design, while hunting was more a factor in eye placement.

Most teeth are for chewing or incising food, and thus I'd expect most teeth styles to be designed for diet. Canines aren't used for eating - they're used for killing. So I'd be surprised to learn that they evolved for diet only. I'm too lazy to do the research, but I'd be happy to be learn I'm wrong. A quick search turned up a somewhat relevant article about large canines in primates (not carnivorous):

http://www.sciencedaily.com/releases/2008/06/080626145058.ht...

It discusses whether they evolved the large canines for fighting or to impress females, but either way it wasn't related to diet.

Actually, if you read further into the article it seems to suggest that, yes, in fact there was a time when hominids had large canines, and we evolved into our current tooth structure.

Interesting link.

Totally right.

Meat and electrolytes, that's what a body needs.

What is this person suggesting?

I'm assuming that the size of a person's brain is based on two things. First, their genes. Second, the environment including diet.

If the researcher is suggesting that diet increases brain size, well that should be easy to measure on living people and will give a fairly definitive answer.

If the researcher is suggesting that eating meat changed our genes, well that needs to be explained.

The older I get the more I realize our biology has an agenda of its own. I wonder if people who smoke cigarettes are really unconsciously building up their immune systems for their great great great grand children for an unforeseen future where the atmosphere gets really bad and they need the immunity to live long lives.

These kinds of thoughts make for great sci-fi.

You know Lamarkism was discredited long ago?

Anyway I do believe a good story could come from there.

That's just biology evolving your brain in such a way that you are hardwired to discredit Lamarkism lest you start interfering with the great plan.

Lamarkism might be seeing a revival. Not really! But something you might see as similar: epigenetics. Scientists are increasingly aware that gene expression is controlled by more than the genes themselves. Some of these control factors may be inheritable.

[citation needed] It's important to be clear what people are talking about when they mention epigenetics. What examples did you have in mind?

He gave you a citation. search on epigenetics. It's seen a lot of headlines in the last couple years.

Where do we see a specific citation in the thread below my question or nearby? A lot of different phenomena have been labeled "epigenetic" in the last few years, without great consistency. I have quite a large number of reference works on genetics at hand in my office, and I was asking specifically which study the HN participant to whom I was replying had in mind.

But could this work with a non-Lamarkian explanation: say most people would smoke, some of them have a random mutation which makes them resistant to it, so they would be more likely to have children and care for them, so the trait would become more common in next generation. Isn't it just darwinian adaptation then?

Except people rarely die before breeding age from smoking (ever?), so no effect.

I guess in older times even dying long after breeding could have had an effect: not being able to look after children => less chance of survival of children carrying same gene.

You are right that in modern society this effect is not so powerful probably, but if we take this reasoning forward, it could mean that diseases of old age will be more and more prevalent as there is no selection pressure for defense against them. Is this happening already?

> Except people rarely die before breeding age from smoking (ever?), so no effect.

Grandparents provide some survival and family size benefits.

with the stigma placed on smoking in many societies smoking could in fact inhibit ones ability to breed (or at least influence it).

Except that the heaviest smokers are often found in the lower classes who also breed more than their rich and middle class comrades.

Epigenetics is the modern incarnation of Lamarkism. While epigenetics doesn't affect the underlying genetic code, some forms of it modify the expression patterns of genes (look up heritability of methylation patterns) which often have an environmentally determined component.

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