

Why do we eat grains? Thermodynamics - lenazegher
http://supplementsos.com/blog/why-do-we-eat-grains/

======
Irregardless
> Eating fewer grain products is not synonymous with popular diets like low-
> carb or gluten-free. It needn’t be borne by commitment to a food movement
> like paleo.

Sure, it doesn't _need_ to be related to the Paleo diet, but that's still
where it all stems from. It's the same as any other fad diet or pseudoscience:
Come up with some reasonable-sounding claims that take advantage of poor
scientific awareness (e.g. _10,000 years isn't enough time for humans to adapt
to eating grains, so we should eat like cave men instead_ ), then make
millions of dollars promoting your diet and selling books to your
unquestioning followers.

There's a common sentiment among Paleo zealots that they finally need to
distance themselves from the irrational underpinnings that started the whole
fad (see here[1] for a FAQ by the 'Paleo diet' inventor). The problem arises
when they go searching for scientific evidence to support their grain bashing,
and then we end up with statements like this:

> It can stem from the simple proposition that fruits and vegetables are
> generally healthier to eat than grains. That’s an argument I’ll cover more
> deeply in later posts.

Oh, how convenient. Save the crux of the argument for another time. We'll all
be patiently holding our breath.

[1] <http://thepaleodiet.com/paleo-diet-faq/>

~~~
michaelkeenan
> 10,000 years isn't enough time for humans to adapt to eating grains, so we
> should eat like cave men instead

One of the details of that argument is that grains contain phytic acid[1],
which humans can't digest. Phytic acid binds with important minerals, such as
calcium, magnesium, iron, and zinc, making them unavailable when digested.
Cows, sheep, goats, and other non-humans produce various phytases, enzymes
that digest phytic acid, but humans don't. Some people (such as Marlene Zuk,
author of Paleofantasy, recently linked on HN) say that 10,000 years is enough
to adapt to a new food, and cite lactose tolerance as an example. But lactose
tolerance is the result of a single SNP, which can occur in at least two
places. To digest phytic acid, humans would need to evolve a whole new enzyme.
You need more than 10,000 years for that.

[1] <http://en.wikipedia.org/wiki/Phytic_acid>

~~~
saalweachter
Two things:

10,000 years is totally enough time for evolution to work on humans. See:
lactose tolerance.

Just as importantly, we've been evolving the living daylights out of every
domestic plant via selective breeding for just as long. Wild potatoes are
poisonous, as are almonds. Maize started out with tiny grain. Apples have been
bred into a bazillion varieties, with different sizes, tastes, and textures.

It's silly to say that it's more natural to eat cauliflower than corn, when
neither properly existed 10,000 years ago.

~~~
jessaustin
_See: lactose tolerance_

GP specifically mentioned that and dismissed it with a seemingly reasonable
argument; care to respond to that? Besides, _most_ humans are not lactose
tolerant as adults. Has there been any research concerning a putative phytic
acid tolerance? If so, have we identified a particular set of relevant genes?
Have we studied the incidence of these genes in various populations?

I sort of assume that humans can handle most compounds they eat on a regular
basis, but it seems that many compounds are harmful when consumed in excessive
amounts.

~~~
saalweachter
Yeah, that was a product of my poor reading; mea culpa and my apologies.

But I do think it is wrong to dismiss lactose tolerance as an example of
recent adaption: most adaptations start as a single mutation with a selective
advantage. It is disingenuous to claim phytic acid would require "a whole new
enzyme", because if an enzyme were evolved specifically to break it down, the
way it'd happen is that an existing enzyme would be duplicated (and there's a
healthy amount of duplication in the typical genome to start with) and a small
number of mutations would specialize this copy for phytic acid. It could be a
single mutation on an already duplicated gene; it could be a series of one or
more random mutations followed by the final mutation which begins to exert a
selective pressure.

But all this is predicated on there being a selective pressure to digest
phytic acid. For lactose, there is a strong selective pressure. For diet-
related prion disorders (kuru), there is a strong selective pressure. Is there
a strong selective pressure to digest phytic acid? Maybe there is, and the
adaptation requires too many mutations to reach. Maybe there isn't, and so
there is no selective pressure to drive an adaptation.

If I am taking the position that grains aren't that bad, then I am also taking
the position that phytic acid -- as it is found in our diets -- isn't
particularly bad. Hence, my position must be that there is no strong selective
pressure to begin digesting phytic acid, anymore than there is to begin
producing our own vitamin C.

~~~
nicholas73
The difference is that the evolution for lactose digestion involves turning
off an already existing gene. Digesting phytic acid involves evolving a new
gene - a new enzyme maker. So you are talking about one random mutation vs.
XXXX mutations.

A genetic study has found that humans did evolve rapidly in the last 10,000
years, but most of the changes were one-off mutations such as these.

------
vanderZwan
" _Scholars continue to argue over whether an increase in population made the
shift towards agriculture necessary, or a shift towards agriculture caused an
increase in population that made a return to a hunter-gatherer society
impossible5. In either case, once the neolithic revolution had begun there was
no turning back._ "

This is an entirely different discussion than what the article is about, but
why are "scholars" assuming those two factors are the only ones to consider?
(assuming they actually are, and this assumption isn't years behind the real
debate going on among the scientists)

There's evidence suggesting that the first time humans cooperated in groups
larger than the default tribe size, it was caused by something completely
different: religion[1]. Göbekli Tepe - the oldest known temple in the world -
predates agriculture[2]. It wouldn't surprise me at all if religion was the
main (if indirect) social driving force behind a lot of these prehistoric
changes in lifestyles that resulted in modern human society.

[1] [http://www.newscientist.com/article/mg21328562.100-the-
god-i...](http://www.newscientist.com/article/mg21328562.100-the-god-issue-
religion-is-the-key-to-civilisation.html?full=true)

[2] <http://en.wikipedia.org/wiki/G%C3%B6bekli_Tepe>

~~~
zeteo
I've been thinking a lot about this and I believe you're correct. Agriculture
appeared in the Near East around 12k years ago, and civilization only around
6k years ago (if we date it by the Uruk period). If agriculture made cities
possible, why did people live in tiny villages for another 6k years after
discovering it?

------
fjorder
Interesting article. Allow me to add a few fun details...

Early agriculturalists actually had it much rougher than this article implies
for a real kicker of a reason:

Wild plants _suck_ as crop plants.

Maize was domesticated from a bushy grass called teosinte (Agriculture arose
independently in the Americas a little later than in the Middle East). Google
that and see how closely it resembles the big juicy corn-cobs you're used to.
Where corn has giant cobs crammed with hundreds upon hundreds of big juicy
kernals, teosinte has a miserly amount of sad, pathetic, and tiny little
kernals. You'd have to grow an entire field full of teosinte to equal the
output of a small patch of corn. If a modern farmer saw one of his fields
being overgrown with teosinte he'd probably spray it with herbicide. If some
contagion wiped out all of our crop plants and we had to go back to wild crops
we would be absolutely _humped_ as a species. Now, imagine how difficult it
must have been to come up with the idea of settling down and growing crops to
live on when the crops you could grow were basically weeds!

In fact, teosinte was so far from being a viable crop that some have proposed
theories about intermediate steps. For example, consider the Beer (or chicha)
theory of civilization! Somehow, somebody discovered that you can ferment
teosinte into something that tastes weird and makes you act even weirder. Fun
stuff! While teosinte was not a crop you could build a viable farm on, maybe
some hunter-gatherers stumbled upon the process of making chicha. At first,
collecting wild teosinte would have taken a lot of work. Far too much for the
calories yielded. However, they probably had the time for the occasional
novelty! Being lazy, these hunter-gatherers probably realized they could
scatter some of the seeds they collected in a specific spot, continue their
wanderings, and find a much denser patch of wild teosinte in the same spot a
year later. They might even have started selecting which seeds to scatter,
either fortuitously preferring the smaller ones for flavor or being smart
enough to deliberately select the mutants with higher yields to sow for next
year. Perhaps the first steps towards agriculture (in the new world at least)
were taken by the paleolithic equivalent of frat-boys! Actually, no
archaeologist would ever say that. They would instead say, "priests and
shamans" used the beer for religious ceremonies. (Hot tip: If archaeologists
have no clue what something they find is for, they usually say it has
"possible religious significance".) It makes no real difference what their
reasons were. In this theory, the selective breeding of teosinte to produce
maize can start long before people actually have to rely on maize to supply
much in the way of calories. Humankind's urge to get plastered may have
ultimately led to civilization!

Wait! There's more! Proponents of this theory have also pointed out that beer
solves a lot of problems early civilizations probably had. Take water quality
for example. If a lot of hunter-gatherer's with no concept of germs or hygiene
were to settle next to a river, you can bet that the river would be pretty
deadly to drink out of before too long. Fortunately, if you take some water,
combine it with grain and ferment it, the result is a tasty fermented beverage
that is safe to drink thanks to the wonders of alcohol! (Early fermented
beverages probably had a pretty low alchohol content and packed a healthy dose
of calories. Perfect for quenching the thirst and nourishing hard working
agriculturalists from dawn till dusk!) I could go on for a while...

TL;DR - Beer, rather than being an evil byproduct of civilization, may be what
gave us both agriculture _and_ civilization! Beer is _good_.

Ham-fisted attempt to tie this back into all-things entrepreneurial: The
development of agriculture was a bit of a chicken-and-the-egg problem. You
can't have agriculture without crop-plants, but how could we have developed
crop plants without agriculture? _Beer_. Sometimes, something that looks like
a total waste of time becomes the foundation of very serious things (TM), such
as the whole of human civilization. Thanks to the adderall-fuelled march of
progress we now get to see this process play out in a matter of years or even
months! Keep your eye on frivolous crap!

~~~
vanderZwan
" _TL;DR - Beer, rather than being an evil byproduct of civilization, may be
what gave us both agriculture and civilization! Beer is good._ "

Similarly, cheese is probably what allowed the lactose-intolerant humans to
transition into lactose tolerance:

[http://www.nature.com/news/art-of-cheese-making-
is-7-500-yea...](http://www.nature.com/news/art-of-cheese-making-
is-7-500-years-old-1.12020)

------
zeteo
Grains are not special because they started being cultivated more intensively
12,000 years ago. They were eaten long before that [1] and intensive
cultivation also applied to veggies [2] and fruits [3] on roughly the same
historical time frame.

[1] <http://en.wikipedia.org/wiki/Ohalo_II>

[2] <http://en.wikipedia.org/wiki/Neolithic_founder_crops>

[3] <http://www.vegparadise.com/highestperch39.html>

------
jond2062
It's unfortunate that a lot of people are so quick to write off a low-carb,
grain-free, or Paleo approach to eating as just another fad. There is actually
an extensive amount of science and research behind the principles.

Yes, some folks are riding the "fad train" and profiting handsomely from the
current popularity. That is true no matter whether it is a diet, a sports
team, or a TV show that is currently en vogue. However, there are quite a few
people who are actually focused on the science and evidence behind human
nutrition and health.

The best book I've come across that dives into the research and nearly every
important epidemiological study in the last 200-300 years is Good Calories,
Bad Calories by Gary Taubes (<http://amzn.to/149HYzi>). It's not exactly an
airplane read and certainly not a "diet" book; however, it completely changed
the way I think about nutrition, exercise, disease, and overall health.

I would also recommend anything by Loren Cordain or Robb Wolf.

Before you make any judgments, do the research.

------
psidebot
"Grains produce more calories per acre than almost all other foodstuffs." -
While this may be true, there are are a couple caveats.

First, the per-acre yields for heritage varietals are much lower than those
cited in the article, and I suspect that some crops have improved quite a bit
more than others.

Second, I would speculate that grains' biggest advantage in neolithic times
was storage duration, not mass or volume. Today if we have a crop-killing
drought we can transport crops from other regions. It's expensive and
inconvenient but not often life threatening. Even as little as a couple
hundred years ago, any society dependent on agriculture would need a crop that
could be stored for multiple years to protect against drought.

------
enigmango
I'm confused about the table in the middle of the article. If rice and corn
have the same amount of kcal per 100g (365), and rice has a higher yield per
acre than corn (7700lbs vs. 6900lbs), how does rice have a lower Calories per
acre number? Is there another conversion I'm not seeing?

~~~
lenazegher
Thank you, fixed. I made an error in unit conversion. Yield figures for corn
are published in bushels/acre, which I had to convert into pounds and then
divide by calories per gram. I'll double check all the other results.

------
SEMW
> Food production has been optimized throughout the entirety of human
> existence. But it has been optimized to solve a problem most people reading
> this article no longer experience. Society no longer needs more food; it
> needs healthier food.

There is an argument that "most people reading this article" shouldn't be
taken in isolation from the rest of the world. The market for food is global.
And there is (according to the UN) a worldwide food shortage[1]. Certainly,
(inflation-adjusted) food prices now way higher than at any point between 1990
and 2007 (though down from peaks in 2008 & 2011)[2].

If demand from first world countries shifts to lower-calorie-per-unit-area
foodstuffs, eventually the global cost of a calorie's worth of food will
increase, exacerbating any food shortage. (Whether that is a good reason not
to move away from grains is a matter for debate -- see the endlessly rehashed
arguments whenever someone brings up food shortages as a reason to be a
vegetarian).

[1] [http://www.guardian.co.uk/global-
development/2012/oct/14/un-...](http://www.guardian.co.uk/global-
development/2012/oct/14/un-global-food-crisis-warning)

[2] [http://www.fao.org/worldfoodsituation/wfs-
home/foodpricesind...](http://www.fao.org/worldfoodsituation/wfs-
home/foodpricesindex/en/)

~~~
dreamdu5t
You're looking at small, recent trends. Food prices adjusted for inflation in
the US are the lowest they've ever been, and Americans spend very little (10%)
of their budgets on food.

[http://familyfarmalliance.clubwizard.com/IMupload/SalemRepor...](http://familyfarmalliance.clubwizard.com/IMupload/SalemReport.pdf)

------
frozenport
>There is nothing intrinsic to lunch that demands bread.

Lunch demands bread, because trying to get 500 calories without a starch is
hard and imbalanced. For example, eating 500 calories of meat is about 50
grams of fat (your done for the day). Eating 500 calories is 10 oranges and a
stomach ache. For the modern day, its not thermodynamics, its because grains
balance our diets.

~~~
romesaz
You seem to associate eating fat with BECOME fat. The two are very different,
and the saturated fat that can be consumed to reach the 500 calories (~70g of
butter vs ~150g of bread) should not be feared.

This too is very much a corner stone of Paleo and the proof is in a lot of
ancient cultures, especially cultures that had to survive through all four
seasons.

------
KirinDave
I can't wait for the followup where the author suggests we all switch to
eating crops that cannot possibly be produced in volume for the world's
population, then that is handwaved away under the implicit assumption that
those people are poor and will probably die of being poor soon anyways.

Because that's ALWAYS where food articles lead when the hosting domain
contains the word "supplements." It's like a 100% probability.

------
venomsnake
I would like to see calories/acre of nuts and olives too - cashew and peanuts
and hazelnuts pack quite the energy punch too. They may be comparable. So
maybe there were other factors at play why grain was chosen as the primary
food source.

~~~
Avshalom
Not a food historian but at a guess: grain can produce a crop from seed in one
season. Fruits/nuts can take years before they produce good yields.

~~~
VLM
You can pack grain away for a typical military campaign pretty well. Nuts go
rancid too fast and fruit rots and is kinda delicate. You can haul wheat from
the north african provinces to london in the roman era pretty well, not so
good for the alternatives.

Its fundamentally a warrior food. You can't conqueror the known world feeding
your legions apples. Wheat, yes, but not pine nuts or oranges.

Sometimes you see this in opposition to non-grain diets, its part of our long
warrior/military tradition, etc etc. You can't have a long term ancient empire
without some kind of grain, otherwise you end up something like Ghengis Kahn
starving horde has to go home. No not the guy Kirk yelled Kahhnn! about, the
much earlier one.

------
confluence
Never really thought about food in this way before - great article.

Which reminds me. Don't you find it funny how some the most important things
to have occurred in history came from the most random places, times and humble
beginnings? I find the fact that such little, seemingly innocuous, random
events go on to have such an enormous impact upon billions of people centuries
into the future absolutely fascinating.

For example have you ever wondered what effectively helped end the need for
slavery and in turn paved the way for women's rights? The steam engine.
Weren't expecting that now then were you?

History is random like that.

~~~
pilsetnieks
On the other hand, you should consider how steam engine development was
prevented in Ancient Greece because of the abundance of slaves. Imagine the
world we'd be living in if that didn't happen.

~~~
meric
The Industrial Revolution didn't happen in China in the 19th century because
of the abundance of cheap labor...

[http://www.voxeu.org/article/why-china-missed-industrial-
rev...](http://www.voxeu.org/article/why-china-missed-industrial-revolution)

"Whereas entrepreneurs in Europe were very eager to develop new technologies
that increased labour productivity via the capital-labour ratio, Chinese
businesses barely had any incentive to do so. "

