8 ms·

A taste for fat may have made us human, says study

60 points by sridca 8y ago

curtis 8y ago
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 8y ago
  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.
roenxi 8y ago
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
- TheSpiceIsLife 8y ago
  Antimatter specific energy: 24,965,421,631,578 Wh/kg! Twenty four thousand nine hundred and sixty five billion watt-hours per kilogram. Weeeeeeeeeeeeeeeeeee!
  - dEnigma 8y ago
    Trillion even. At least when using the short scale. https://en.wikipedia.org/wiki/Long_and_short_scales https://en.wikipedia.org/wiki/Long_and_short_scales
- saagarjha 8y ago
  > 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 8y ago
    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 8y ago
      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 8y ago
        Hydrocarbons are C_nH_m
vezycash 8y ago
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 8y ago
  Liver is generally high in vitamins (notable A) and minerals.
- kopos 8y ago
  Even in countries like Japan, organ meats are relished along with the muscle meats.
wahern 8y ago
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.
- cageface 8y ago
  Exactly. Personally I find the argument that it was cooking that enabled us to evolve a lot more compelling. It's certainly not something any other species does and it unlocks a lot of new calories.
- forgotmypw2 8y ago
  Have you heard of a book titled "the mating mind"?
- ppod 8y ago
  > 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.
vfc1 8y ago
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 8y ago
  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 8y ago
    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 8y ago
      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.
      - peteradio 8y ago
        Why come did bears evolve to steal my pickinickbasket them?
samatman 8y ago
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.
- simonh 8y ago
  selecting good rocks for throwing, collecting them, playing and practicing with them. Breaking up bigger rocks and shaping them to make better ones for throwing. Ouch! Some of those broken off shards are sharp. hmmm.....
- nfg 8y ago
  If you haven’t read William Calvin’s “The Ascent of Mind” you might enjoy it: http://williamcalvin.com/bk5/bk5.htm http://williamcalvin.com/bk5/bk5.htm The “throwing theory” features prominently.
- FrozenVoid 8y ago
  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1571064/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1571064/
- BerislavLopac 8y ago
  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/snow-monkeys-hot-springs https://www.seejapan.co.uk/where-to-go/outdoors/hot-springs/... [1] https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis#Related_academic_and_independent_research https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis#Related...
xvilka 8y ago
Now it is a good time to stop then. Both consumption and production (by organism).
DiabloD3 8y ago
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.
- seekingcharlie 8y ago
  Diabetes II can also be “cured” by a high carb low fat diet. Not all carbs are equal; the problem is refined carbs.
  - ZeroFries 8y ago
    You can cure diabetes with refined rice, fruit, fruit juice, and sugar diet (Kempner rice diet). The problem isn't any particular macronutrient, it's most likely an excess of calories.
- londt8 8y ago
  I have understood that saturated fats are bigger culprit for type 2 diabetes than high carb intake. Also sugars are larger risk than carbs in general.
  - will_brown 8y ago
    Type 2 is insulin resistance. In other words your body produces insulin to clear sugar from the blood but the body no longer responds (actually clears the sugar from the blood) to insulin. The resistance (type 2) is built up over time (historically it was “adult onset”) to insulin spikes. I don’t believe saturated fats introduce sugar into the blood, so they don’t cause insulin spikes, which means they don’t contribute to resistance (at least not directly). In a roundabout way they may contribute to a surplus of calories and the storage of fat, ultimately causing obesity, which does seem to speed up the resistance to insulin. But all things being equal the same surplus of calories on a high carb diet will be more detrimental because there will be insulin spikes and the insulin will also enlarge fat cells allowing the body to store more fat (ie become obese more efficiently).
avinium 8y ago
“It actually takes more work to metabolize lean protein than you get back.” Is this correct? I've never heard this position before.
- darkpuma 8y ago
  Sounds like a reference to "rabbit starvation", which is real but a pretty difficult situation to get yourself into.
  - someone454 8y ago
    If there’s a term for it then it can’t be that hard to get into..
mannykannot 8y ago
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.
lucidguppy 8y ago
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 8y ago
  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 ;-)
- Footkerchief 8y ago
  Human != civilized
crazygringo 8y ago
> 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-processed-foods https://www.precisionnutrition.com/digesting-whole-vs-proces... [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-cholesterol-content-wild-game https://news.psu.edu/story/186616/1997/12/10/fat-and-cholest... [4] https://en.wikipedia.org/wiki/Protein_poisoning https://en.wikipedia.org/wiki/Protein_poisoning

60 points by sridca 8y ago

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 8y ago
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.

roenxi 8y ago

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

TheSpiceIsLife 8y ago
Antimatter specific energy: 24,965,421,631,578 Wh/kg! Twenty four thousand nine hundred and sixty five billion watt-hours per kilogram. Weeeeeeeeeeeeeeeeeee!
- dEnigma 8y ago
  Trillion even. At least when using the short scale. https://en.wikipedia.org/wiki/Long_and_short_scales https://en.wikipedia.org/wiki/Long_and_short_scales
saagarjha 8y ago
> 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 8y ago
  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 8y ago
    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 8y ago
      Hydrocarbons are C_nH_m

vezycash 8y ago

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 8y ago
Liver is generally high in vitamins (notable A) and minerals.
kopos 8y ago
Even in countries like Japan, organ meats are relished along with the muscle meats.

wahern 8y ago

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.

cageface 8y ago
Exactly. Personally I find the argument that it was cooking that enabled us to evolve a lot more compelling. It's certainly not something any other species does and it unlocks a lot of new calories.
forgotmypw2 8y ago
Have you heard of a book titled "the mating mind"?
ppod 8y ago
> 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.

vfc1 8y ago

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 8y ago
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 8y ago
  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 8y ago
    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.
    - peteradio 8y ago
      Why come did bears evolve to steal my pickinickbasket them?

samatman 8y ago

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.

simonh 8y ago
selecting good rocks for throwing, collecting them, playing and practicing with them. Breaking up bigger rocks and shaping them to make better ones for throwing. Ouch! Some of those broken off shards are sharp. hmmm.....
nfg 8y ago
If you haven’t read William Calvin’s “The Ascent of Mind” you might enjoy it: http://williamcalvin.com/bk5/bk5.htm http://williamcalvin.com/bk5/bk5.htm The “throwing theory” features prominently.
FrozenVoid 8y ago
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1571064/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1571064/
BerislavLopac 8y ago
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/snow-monkeys-hot-springs https://www.seejapan.co.uk/where-to-go/outdoors/hot-springs/... [1] https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis#Related_academic_and_independent_research https://en.wikipedia.org/wiki/Aquatic_ape_hypothesis#Related...

xvilka 8y ago

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

DiabloD3 8y ago

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.

seekingcharlie 8y ago
Diabetes II can also be “cured” by a high carb low fat diet. Not all carbs are equal; the problem is refined carbs.
- ZeroFries 8y ago
  You can cure diabetes with refined rice, fruit, fruit juice, and sugar diet (Kempner rice diet). The problem isn't any particular macronutrient, it's most likely an excess of calories.
londt8 8y ago
I have understood that saturated fats are bigger culprit for type 2 diabetes than high carb intake. Also sugars are larger risk than carbs in general.
- will_brown 8y ago
  Type 2 is insulin resistance. In other words your body produces insulin to clear sugar from the blood but the body no longer responds (actually clears the sugar from the blood) to insulin. The resistance (type 2) is built up over time (historically it was “adult onset”) to insulin spikes. I don’t believe saturated fats introduce sugar into the blood, so they don’t cause insulin spikes, which means they don’t contribute to resistance (at least not directly). In a roundabout way they may contribute to a surplus of calories and the storage of fat, ultimately causing obesity, which does seem to speed up the resistance to insulin. But all things being equal the same surplus of calories on a high carb diet will be more detrimental because there will be insulin spikes and the insulin will also enlarge fat cells allowing the body to store more fat (ie become obese more efficiently).

avinium 8y ago

“It actually takes more work to metabolize lean protein than you get back.” Is this correct? I've never heard this position before.

darkpuma 8y ago
Sounds like a reference to "rabbit starvation", which is real but a pretty difficult situation to get yourself into.
- someone454 8y ago
  If there’s a term for it then it can’t be that hard to get into..

mannykannot 8y ago

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.

lucidguppy 8y ago

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 8y ago
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 ;-)
Footkerchief 8y ago
Human != civilized

crazygringo 8y ago

> 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-processed-foods https://www.precisionnutrition.com/digesting-whole-vs-proces... [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-cholesterol-content-wild-game https://news.psu.edu/story/186616/1997/12/10/fat-and-cholest... [4] https://en.wikipedia.org/wiki/Protein_poisoning https://en.wikipedia.org/wiki/Protein_poisoning