
A taste for fat may have made us human, says study - sridca
https://news.yale.edu/2019/02/05/taste-fat-may-have-made-us-human-says-study
======
samatman
Since we’re all throwing out our pet theories today, here’s mine: throwing
rocks.

As the forests retreated, smallish apes were forced onto the grasslands and
had to compete in a different habitat. No claws to work with, no real fangs to
speak of. Just a grasping thumb, an upper body shaped by brachiation, and a
habit of flinging feces at other apes challenging them for territory.

Rocks can drive predators off carcasses and kill smaller animals. Getting
better at throwing rocks brings in more food. An upright posture helps, a
bigger brain for visuospacial processing helps.

Eventually we were bigger apes and picked up persistence hunting, spear
making, ax making, and fire. Persistence hunting was a group cooperative
effort driving us toward protospeech.

True speech is admittedly a bit of a head-scratcher. Lucky mutation maybe?
Fairly confident about the rocks, though. Once you’re throwing rocks, smashing
bones open for the marrow is a pretty obvious move.

~~~
BerislavLopac
My personal favourite is the hypothesis that human ancestors had for an
extended period lived wading in shallow water, which protected them from
climate (i.e. either warm springs in cold climate, or regular water in warm
ones; we can see similar behaviour among modern monkeys and apes in some
circumstances [0]) and possibly from natural predators.

They were not constrained to the water, often leaving it to forage for food
and possibly hunt, but regularly returning to its safety. Eventually the
climate changes forced them to leave the wading lifestyle and adapt to steppes
and other habitats, using their growing intellect to devise adaptations like
clothes, tools and at some point mastery of fire.

This would, in my mind, explain a number of specific development present in
humans in a very rare combination:

\- nearly complete loss of body hair, except on the head (which is consistent
with wading) \- adaptations for both swimming/diving and two-legged walk \-
development of speech and facial expressions as communication tools, which
work the best when the rest of the body cannot be used \- importance of fish
in human diet \- increased brain in children, which causes more difficult
births, which are offset but giving birth in water

This is a variant of what used to be known as "aquatic ape hypothesis" and
widely ridiculed, but more resent research has supported some of its elements
[1].

[0] [https://www.seejapan.co.uk/where-to-go/outdoors/hot-
springs/...](https://www.seejapan.co.uk/where-to-go/outdoors/hot-springs/snow-
monkeys-hot-springs)

[1]
[https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis#Related...](https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis#Related_academic_and_independent_research)

~~~
Swizec
> \- nearly complete loss of body hair, except on the head (which is
> consistent with wading)

It's also consistent with running. Running creates _a lot_ of energy. Like a
lot. You know when it's sub 10 celsius out and everyone is freezing their
butts off? You go for a run in tiny tiny shorts and a tiny little t-shirt and
yes it's freezing your nips off but 3 miles later you're sweating balls and
wishing the t-shirt was smaller and the shorts even tinier.

They say the perfect temperature for a marathon is around 4 celsius. That's
because when you're fast enough, heat dissipation is pretty much the only
limiting factor to how fast you can run. Even an amateur runner like me can
see huuuuuge gains in speed just from running in temperate winter instead of
during summer.

~~~
BerislavLopac
Many animals run and still retain their fur. Pretty much all of the known
mammals that have lost most of their fur/hair are either aquatic (whales,
dolphins, dugongs...) or regular waders (pigs, hippos, elephants...); the only
exceptions live underground or in crevices.

------
DiabloD3
The brain runs almost entirely on beta-hydroxybuterate, and human mitochondria
have a very efficient process to use BHB (instead of glucose) for power.

The most efficient diet for humans is one high in fat, moderate in protein,
and low in carbs; which explains the absolutely curable disorder known as
Diabetes II (aka chronic insulin resistance).

And before anyone jumps on the "keto is a fad diet" bandwagon: if it is,
indeed, a fad, it is a fad that modern humans have eaten for 200,000 years,
and our ancestors have eaten for another 2 million before that. If our taste
for fat did not make us human, it certainly defines a particular trait of ours
that all humans depend on.

~~~
lustysocietyorg
> The brain runs almost entirely on beta-hydroxybuterate

This is not true.

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3900881/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3900881/)

Quote: The mammalian brain depends upon glucose as its main source of energy,
and tight regulation of glucose metabolism is critical for brain physiology.

[https://www.ncbi.nlm.nih.gov/pubmed/27826689](https://www.ncbi.nlm.nih.gov/pubmed/27826689)

Quote: β-Hydroxybutyrate (βOHB), a ketone body, is oxidised as a brain fuel.
Although its contribution to energy metabolism in the healthy brain is
minimal, it is an interesting metabolite which is not only oxidised but also
has other direct and collateral effects which make it a molecule of interest
for therapeutic purposes.

> The most efficient diet for humans is one high in fat, moderate in protein,
> low in carbs;

This is not true.

Scientifically proven best diet: Whole food plant based high carb, low-
moderate fat and low protein.

Unless the body is starving, fat and protein are not converted to glucose (the
main energy source for cells) to cover energy needs.

Fat Consumption is the Only Cause of Weight Gain (2018-07-14).
[https://neurosciencenews.com/fat-consumption-weight-
gain-957...](https://neurosciencenews.com/fat-consumption-weight-gain-9573/)

Why Doctors Don't Recommend A Vegan Diet | Dr. Michael Greger (2015-05-17).
[https://www.youtube.com/watch?v=_d1Ca6SsKfE](https://www.youtube.com/watch?v=_d1Ca6SsKfE)

Dr Garth Davis: Americans have become obsessed with Protein (2015-10-28).
[https://www.youtube.com/watch?v=XQCt3IhaUtU](https://www.youtube.com/watch?v=XQCt3IhaUtU)

Omnivore or Herbivore? [https://livinontheveg.com/omnivore-or-
herbivore/](https://livinontheveg.com/omnivore-or-herbivore/)

Besides:

[https://www.youtube.com/channel/UCGJq0eQZoFSwgcqgxIE9MHw/vid...](https://www.youtube.com/channel/UCGJq0eQZoFSwgcqgxIE9MHw/videos)

~~~
callmeal
>>Fat Consumption is the Only Cause of Weight Gain (2018-07-14).
[https://neurosciencenews.com/fat-consumption-weight-
gain-957...](https://neurosciencenews.com/fat-consumption-weight-gain-9573/)

Wow the sugar industry is still at it. Read the abstract. The study concludes
that mice are incapable of auto-regulating caloric intake because fat
stimulates their pleasure pathways causing them to overeat. Kinda like how
sugar behaves in humans. See the graphical abstract[0] for a pictorial
depiction the authors have helpfully provided.

[0]: [https://www.cell.com/cell-
metabolism/fulltext/S1550-4131(18)...](https://www.cell.com/cell-
metabolism/fulltext/S1550-4131\(18\)30392-9#secsectitle0015)

~~~
lustysocietyorg
You are right to question this study and the conclusion of the article. Still,
the study shows some important points:

\- Professor John Speakman, who led the study, said: “The result of this
enormous study was unequivocal – the only thing that made the mice get fat was
eating more fat in their diets.

\- “Carbohydrates including up to 30% of calories coming from sugar had no
effect. Combining sugar with fat had no more impact than fat alone. There was
no evidence that low protein (down to 5%) stimulated greater intake,
suggesting there is no protein target. These effects of dietary fat seemed to
be because uniquely fat in the diet stimulated the reward centres in the
brain, stimulating greater intake.

Anyway, one has to wonder why the body has a natural tendency to eat carbs
(only in plants like healthy fiber) if they are not part of the natural diet:
Sweet fruits. Sweet vegetables. Sugar. Starch products. Processed meat with
vegetable spices and not just bloody pure meat like carnivores with the
appropriate digestive system.

Sugar and Fat Bingeing Have Notable Differences in Addictive-like Behavior
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2714381/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2714381/)

WHY LOW CARB DIETS ARE A SCAM (2016-11-30).
[https://www.youtube.com/watch?v=1dj-
Wmmt0FE&feature=youtu.be...](https://www.youtube.com/watch?v=1dj-
Wmmt0FE&feature=youtu.be&t=442)

The Science of Cheese Addiction (2017-03-25)
[https://www.youtube.com/watch?v=1hE6lhQu7k4](https://www.youtube.com/watch?v=1hE6lhQu7k4)

~~~
cheesymuffin
You're wrong about most things but it's definitely cool to see cheese
addiction come up in mainstream media. I used to eat whole blocks of the stuff
at a time and when I quit I was literally shivering. That stuff might be
alright in small doses if you have an eating disorder and need to make food
more palatable, but it is not good for adults.

~~~
Robotbeat
As a Midwesterner, I feel attacked.

EDIT: in all seriousness, I appreciate your anecdote. This thread is
convincing me of how little I know.

------
roenxi
The energy density table on Wikipedia [0] says it all really. Sort it by
specific energy, and marvel at how animal fat is baaasicaly jet fuel.

Also take a moment to appreciate exactly what nuclear power implies in terms
of bang-for-buck mining and transport costs.

[0]
[https://en.wikipedia.org/wiki/Energy_density](https://en.wikipedia.org/wiki/Energy_density)

~~~
saagarjha
> marvel at how animal fat is baaasicaly jet fuel

Fat seems to be with the rest of the hydrocarbons in this regard, which is not
surprising since it's one of them.

~~~
cheesymuffin
Fatty acids are _not_ hydrocarbons as they all contain a carboxyl group. Fats
have distinctly lower free energy than hydrocarbons.

Also, animal fat is a tissue, not an organic molecule, so there's a little bit
more complexity here.

~~~
saagarjha
I never was really good at chemistry, but I'm sure I've heard lipids being
referred to as "hydrocarbons". Aren't they mostly long chains of hydrogen and
carbon? Is it fair to call them "hydrocarbons" in this case?

~~~
cheesymuffin
Hydrocarbons are C_nH_m

------
vfc1
Cooking unlocks a lot of calories and nutrients, especially starchy food like
potatoes and other root vegetables.

These are usually not eaten by most animals, and are available almost
everywhere close to year-long, plus they can be stored for later in a dry
place.

The human brain consumes a huge amount of calories, so cooking which was done
millions of years before homo sapiens arrived as definitively a lot to do with
becoming a modern human.

A more intriguing question is, how did cooking start, and how did apes became
intelligent enough in order to know how to cook?

~~~
whatabackend
Cooking is so straightforward that it would be astonishing if it weren't
discovered. There is a fire in the jungle; hungry humans discover a cooked
chicken near the perimeter and realize it was the hot fire that caused it to
smell and taste so good. Next time, they go to a fire, capture it and control
it to cook some meat. From here, it's monkey see monkey do and the rest is
history.

~~~
mrob
Why would it smell and taste unusually good before cooking was invented? Isn't
it more likely that appreciation for the taste of cooked food evolved because
cooked food is safer and more nutritious? If there's no cooked food there's no
reason for this preference to evolve.

~~~
koolba
It may be the stronger smell or the faster delivery of particulates of burnt
fat through the air.

Dogs, wolves, and bears can’t cook or start fires but all of them are
attracted to the smell of cooked food as well. You could argue that dogs and
_maybe_ wolves co-evolved that preference alongside ours, but that doesn’t
hold up for bears.

~~~
BoiledCabbage
Are bears attracted to the smell of cooked food? Or just attracted to the
smell of food, and cooking is how most people treat food out in the
wilderness?

------
crazygringo
> _The paper argues that this theory does not make nutritional sense. “The
> meat of wild animals is lean,” Thompson says. “It actually takes more work
> to metabolize lean protein than you get back.” In fact, eating lean meat
> without a good source of fat can lead to protein poisoning and acute
> malnutrition. Early Arctic explorers, who attempted to survive on rabbit
> meat exclusively, described the condition as “rabbit starvation.”_

What? It's simply not true that lean protein takes more energy to digest than
it produces -- it takes 20-30% of the energy to digest it, not >100% [1]. It's
not celery -- and even the idea that celery is a "negative-calorie food" turns
out to be a myth [2], so it's basically ridiculous to suggest that meat could
be.

And while wild animals can have somewhat leaner meat, there's _plenty_ of fat,
see the table in [3], and seeing as animals really were abundant back then, it
would be easy to eat as much fat as you wanted (remember, it comes in big
chunks) and throw away any excess super-lean muscles.

And to be clear, despite the name, "rabbit starvation" is about _vitamin_
deficiency, not calorie deficiency. [4]

Since these quotes are coming from the paper's author, I'm finding the whole
thing highly suspect... intriguing, but hard to take seriously with such
factual inaccuracies.

[1] [https://www.precisionnutrition.com/digesting-whole-vs-
proces...](https://www.precisionnutrition.com/digesting-whole-vs-processed-
foods)

[2] [https://en.wikipedia.org/wiki/Negative-
calorie_food](https://en.wikipedia.org/wiki/Negative-calorie_food)

[3] [https://news.psu.edu/story/186616/1997/12/10/fat-and-
cholest...](https://news.psu.edu/story/186616/1997/12/10/fat-and-cholesterol-
content-wild-game)

[4]
[https://en.wikipedia.org/wiki/Protein_poisoning](https://en.wikipedia.org/wiki/Protein_poisoning)

------
lucidguppy
Take away fire and starches/grains and you take away civilization. Grazing is
for extracting calories from marginal land. Prime land isn't given to animals
to graze on - it's given to plants. Once we knew how to harvest corms and
tubers and cooked them we became more starvation proof. (Hunting is more hit
or miss).

Starch granule are found in the teeth of many hominid fossils. We produce
amylase in our saliva which breaks down cooked starches when it hits our
tongues. Other omnivores do not have this adaptation.

You cannot have a high fat diet hunting (deer and small game simply do not
have high amounts of fat). We moved on to agriculture because it provided
plenty of calories and didn't run away from us when we tried to kill it.

While we may have eaten fat opportunistically - it's starches and fire that
got us to where we are.

~~~
kingofhdds
The study explores the possible way to sustain a bigger brain well before
invention of tools, and controlled fire. It's also absolutely not about
hunting.

It's always hit or miss when one tries to comment after reading just a
headline ;-)

------
wahern
The crucial driver for the emergence of an utterly and uniquely distinct
intelligence is a source of nutrition available to countless other predators
for hundreds of millions of years? Makes perfect sense... unless you believe
in natural selection.

Natural selection tells us the process typically works in the reverse order:
environmental pressures create a situation where the emergence of increased
intelligence grants the individual an ability to leverage the calorie source
to their _distinct_ reproductive advantage; not just relative to lions but
relative to those in their group. So the marginally improved intelligence
mutation occurs first, _and_ it has to be so advantageous that it can overcome
counterveiling selective pressures such as more aggressive individuals simply
taking the calorie rich source. Were it otherwise we'd be living in Planet of
the Apes, or more likely would never have existed.

Whatever evolutionary strategy our ancestors found themselves pursuing, it
almost certainly must have been unique and special. The notion that we
developed intelligence because intelligence intrinsically provides a
reproductive advantage doesn't make any more sense than the notion that we
developed intelligence because we could eat fat. Such simple strategies are
immediately, incrementally, and perpetually available to countless species,
now, then, and prior. If it were true it would imply that evolution is a
simple escalator for traits like intelligence, but we see no such evidence of
that.

~~~
ppod
> And the only things that could crack open these containers, she adds, were
> the bone-cracking jaws of hyenas or a clever ape wielding a rock.

The authors do mention that. It was written by three professors of evolution
and anthropology at Yale, Oxford, and Uni Chicago, but the first comment here
is dismissive snark.

>We propose that the regular exploitation of large-animal resources—the “human
predatory pattern”—began with an emphasis on percussion-based scavenging of
inside-bone nutrients, independent of the emergence of flaked stone tool use.
This leads to a series of empirical test implications that differ from
previous “meat-eating” origins scenarios.

~~~
wahern
My bone to pick isn't with the scholarship on the particulars of human hunting
patterns. It's with the conclusions related to the evolution of intelligence.

There's a tendency to think that human intelligence arose because of a series
of serendipitous adaptations that permitted intelligence to blossom--eating
marrow, eating meat, having opposable thumbs, bipedalism, complex
vocalizations, etc. But every time a researcher tries to differentiate humans
along an axis, we later discover that these adaptations are actually quite
pervasive.

Tool use, communication, calorie sources, etc... whatever early humans did we
eventually find to actually be quite pervasive in the sense of independently
arising. Which suggests that none of these alone is any sort of bottleneck to
intelligence. And if such adaptations are incrementally available then why is
it human intelligence exploded so? What's the bottleneck? The only response,
again, is some sort of cosmic serendipity along the whole chain, but that's
conclusory without any evidence (i.e. showing the bottleneck that prevents all
these other species from continuing down the same path and, most importantly,
why humans are uniquely capable of squeezing through these bottlenecks time
and again).

The scholarship in the article is interesting and useful, but as it regards
intelligence it doesn't even begin to answer the critical questions.

------
curtis
If you use a rock to smash up a bone to get to the marrow, I wonder if you
also get, as a side-effect, a bunch of bone flakes, some of which are sharp
enough to be used as a cutting implement. Maybe primitive hominids were
smashing bones for sharp flakes before they started flaking rocks to make
cutting tools.

~~~
blihp
Before you get there, the bones would have been used as clubs and sharp broken
bones used as proto-spears or knives.[1] Then after some period of time, it
would seem reasonable that already recognizing the utility of the bones that a
slightly more evolved creature would start to put the pieces together (pun
intended) and find uses for bone chips/flakes for ever more effective tools. I
can't even imagine how much time must have passed before this came together to
get early us even that far.

[1] Which in turn would have come about after a long period of time just using
rocks before those evolving primates discovered their advantages as
tools/weapons.

------
mannykannot
Some years ago, I came across a paper suggesting something similar, except
that the key dietary change was when an ancestor hominin (I don't recall
which, if they identified a specific one) switched from a largely fish-based
diet to one of land mammals. The paper seemed to take as as established fact
that there was, at one time, a hominin with a fish-based diet.

I have not been able to track down this paper again, but the idea that
adopting an aquatic diet was a step in the evolution of homo sapiens seems to
be 'in the air'; this paper seemed to be saying that a subsequent switch away
from that diet was also important. IIRC, it included both a nutritional
argument, and the point that it allowed this hominin to spread beyond lake-
shores and coastlines.

------
avinium
“It actually takes more work to metabolize lean protein than you get back.”

Is this correct? I've never heard this position before.

~~~
darkpuma
Sounds like a reference to "rabbit starvation", which is real but a pretty
difficult situation to get yourself into.

------
xvilka
Now it is a good time to stop then. Both consumption and production (by
organism).

------
vezycash
Carnivores like lions first eat internal organs like liver & kidney.
Apparently these contain a nice mix of fat and protein. Even orcas preying on
whales just eat the liver and leave the rest.

Question is why.

My brief research after reading this article showed that cats can't produce
their own fat or proteins. And are poor in taking energy from carbohydrates.

Since they can't get their energy from carbs, they eat fat along with
proteins.

Say our ancestors couldn't farm. Or were carnivores then it makes sense that
they'd seek fat source by instinct just to stay alive.

The argument that fat eating made us human is fiction.

~~~
saagarjha
Liver is generally high in vitamins (notable A) and minerals.

