Did we evolve to eat meat?

[Dirk]

- How have humans evolved to need supplements? How can we even take up the vitamins and minerals out of supplements as we could from whole foods?

- If we are evolved to eat meat, then why is our digestive tract much longer than that from meat-eaters?

- Why don't I salivate at the sight of an animal when I am hungry? I figure that would be a normal reaction if I was evolved to eat them.

- If eating meat is recommended, why are there tons of people thriving on vegetarian diets?

- Why am I able to build substantial muscle when I eat only 5% of my caloric intake is from protein (at about 3000 calories a day -> 150 calories from protein -> about 35 grams of protein/day) coming from fruits and leafy greens solely?

- Why am I able to feel great and others too when eating a low fat raw vegan diet?

- Why are there differences in what people can and need to eat? Isn't there just one type of diet for all of us, just as with any other species?

To clarify, I do eat meat at the moment.

Edit: By no means I want to troll or challenge your thinking. I genuinely have no answer to these questions in the context you are sketching.

 

[mkrnhr]

Re: Questions

Hello Dirk,
On the minerals in a simple way:
In nature, there is a cycle of minerals: Ground->Plants->Animals in the first movement, then, Plants->Ground and Animals->Ground in the second movement. The minerals are than more or less constant in the ground and in the living forms depending on it.
With the arrival of mass farming, the second step is not fullfilled. So with time, there are less and less minerals and the agricultural products have thus less and less minerals.
We used to learn about nature cycles in school in the 80s (life cycle, carbon cycle, water cycles, minerals, etc.) but today they do not learn that anymore, all has been linearized.

The other questions you can find out by reading, not having a preconceived opinion. The question about salivating to the view of an animal is a very stupid one, unless i don't understand it due to a different cultural background.

 

[Dirk]

Re: Questions

The question about salivating to the view of an animal is a very stupid one, unless i don't understand it due to a different cultural background.

Why is it a stupid one? If I am supposed to eat it, I would say it would be normal to salivate instead of being disgusted by even only the thought of killing it?

 

[Dirk]

Re: Questions

Hello Dirk,
On the minerals in a simple way:
In nature, there is a cycle of minerals: Ground->Plants->Animals in the first movement, then, Plants->Ground and Animals->Ground in the second movement. The minerals are than more or less constant in the ground and in the living forms depending on it.
With the arrival of mass farming, the second step is not fullfilled. So with time, there are less and less minerals and the agricultural products have thus less and less minerals.
We used to learn about nature cycles in school in the 80s (life cycle, carbon cycle, water cycles, minerals, etc.) but today they do not learn that anymore, all has been linearized.

Fair enough, but you agree, farming on ground where the second step IS fulfilled would be better than taking supplements?

 

[Tigersoap]

Re: Questions

Maybe this will be of interest for you :

Burying The Vegetarian Hypothesis

 

[Dirk]

Re: Questions

Maybe this will be of interest for you :

Burying The Vegetarian Hypothesis

What a nonsense article. At least, a nonsense conclusion.

However, total metabolic rate is determined by the size of the organism. As the mass of an organism goes up, so does the heat that it gives off in a neat linear relationship. An animal the size of a mouse gives off less heat than an animal the size of a human, who gives off less heat than an animal the size of a horse. The formula that determines metabolic rate with respect to mass is known as Kleiber's Law, named after Max Kleiber who discovered it. Because of Kleiber's Law, the metabolic rate of any animal can be predicted given its mass.

Nonsense. The heat an animal gives off (assuming body temperature is equal) doesn't scale linearly with mass, but scales linearly with bodily surface, in other words, surface of the skin. This does not only depend on the mass, but also on the shape and composition of the creature.

Given that a large gut is needed to extract enough energy from a vegetable-based diet, regardless of the need for a larger brain size, if a vegetarian diet is maintained, increasing brain size is not possible without violating Kleiber's Law.

Nothing digests easier than fully ripe fruits. If Kleiber's law is true (which might very well not be, see quote above) and due to increased metabolic rate of the brain, the gut size needs to decrease. That means that the body needs foods that are EASIER to digest.

I totally agree that grass, soy, grains or cruciforous vegetables cost a lot of energy to extract energy from. So that is not the way to go. Extracting energy from ripe fruits and leafy greens is easy however.

This article seems like an excellent way to advocate fruitarianism with the addition of leafy greens for adequate supply of minerals. No meat necessary.

 

[Laura]

Re: Questions

- How have humans evolved to need supplements? How can we even take up the vitamins and minerals out of supplements as we could from whole foods?

People didn't evolve to need supplements. However, due to the toxicity of the greed driven Western diet, added to the fact that most foods that are available - even if they are generally "natural" - are devoid of the intense nutritional elements that used to be the characteristic of foods in times before the greed driven Western way of raping the planet took over.

Thus, it is often necessary to utilize supplements to get out of the vicious feedback loop of toxicity. Read Sherry Rogers' book "Detoxify or Die" and Baker's book "Detoxification and Healing." (Many others identify these problems in detail.

- If we are evolved to eat meat, then why is our digestive tract much longer than that from meat-eaters?

I think you are suffering from misinfo. Read:
Burying The Vegetarian Hypothesis
and: The Naive Vegetarian


just for starters. We have a list of dozens of books and hundreds of papers on this topic we can provide.

 

[Mr. Premise]

Re: Questions

Dirk, it also makes sense to view all this in terms of goals and aims. When you refer to biological evolution, the point is just to make sure the organism survives to reproduction (understanding "reproduction" in human terms means some upbringing of children and maybe even some grandparenting). So yes, humans evolved as omnivores, not carnivores, but our aim in this very unique time of cataclysm is necessarily different. In other words we are looking to optimize nutrition to survive extreme stress in order to achieve an AIM.

 

[Dirk]

Re: Questions

People didn't evolve to need supplements. However, due to the toxicity of the greed driven Western diet, added to the fact that most foods that are available - even if they are generally "natural" - are devoid of the intense nutritional elements that used to be the characteristic of foods in times before the greed driven Western way of raping the planet took over.

Thus, it is often necessary to utilize supplements to get out of the vicious feedback loop of toxicity. Read Sherry Rogers' book "Detoxify or Die" and Baker's book "Detoxification and Healing." (Many others identify these problems in detail.

I have a read a ton of this and I see the point here.

I think you are suffering from misinfo. Read:
Burying The Vegetarian Hypothesis

Just commented on that. Highly flawed article as stated above.

The Naive Vegetarian

Flawed article too.

The first evidence lies in the fossil sites. Where hominid remains are found, so also are animal bones - at times in their thousands. If we were not meat-eaters, why is that?

I immediately believe that, but the fact that we ate animals, doesn't mean we have evolutionary adapted to eat them.

Secondly, although modern hunting tribes do eat plants, they have fire. Without it, there are very few plant foods with sufficient calorific value that we could have digested. There were fruits, of course, but there is not one prehistoric site in all Africa that indicates forests extensive enough to have supplied sufficient fruit to meet the needs of its inhabitants. Indeed, there is agreement that our ancestors did not dwell in forests at all but on the savannahs where there were vast plains of grass. However, grass is of no value to our digestive system. Even to live off fleshier leaves would require the much more highly specialised digestive systems of other primates. Compare the shape of the gorilla against that of the man in Figure 3. The area between the chest and the legs of the gorilla is much greater than the same part of the man. This is because the gorilla, a herbivore, needs a much larger digestive system. The walls of all plant cells are made of cellulose, a form of dietary fibre. There is no enzyme in the human digestive system that will break it down. And with the cell walls intact, the nutrients in the cells cannot be digested. Passing unaffected straight through the gut, therefore, all the nutrients in the plant would be ejected as waste.

We do best at temperatures between 20 to 25 degrees celcius. We haven't evolutionary adapted to other circumstances, though we can artificially create them. Only regions where it is consistently 20 to 25 degrees celcius shows us the circumstances that we are evolutionary adapted too. There is plenty of fruit in those regions. Yes, we have lived on other foods and other circumstances, but since we still need a warm climate and lots of sun to be able to thrive without artificially created circumstances my guess is that we also haven't evolutionary adapted to the foods we ate in the artificial circumstances (clothing, heating, etc..).

Fats and brain size

The evidence was already overwhelming that we could not be a vegetarian species. However, in 1972 the publication of two independent investigations really nailed the lid on the vegetarian hypothesis's coffin. The first concerned fats (9) .

About half our brain and nervous system is composed of complicated, long-chain, fatty acid molecules. The walls of our blood vessels also need them. Without them we cannot develop normally. These fatty acids do not occur in plants. Fatty acids in a simpler form do but they must be converted into the long-chain molecules by animals - which is a slow, time-consuming process. This is where the herbivores come in. Over the year, they convert the simple fatty acids found in grasses and seeds into intermediate, more complicated forms that we can convert into the ones that we need.

Our brain is considerably larger than that of any ape. Looking back at the fossil record from early hominids to modern man, we see a quite remarkable increase in brain size. This expansion needed large quantities of the right fatty acids before it could have occurred. It could never have occurred if our ancestors had not eaten meat. Human milk contains the fatty acids needed for large brain development - cow's milk does not. It is no coincidence that in relative terms, our brain is some fifty times the size of a cow's.

The vegetarian will be dismayed to learn that while soya bean is rich in complete protein, and grains and nuts also combine to provide complete proteins, none contains the fats that are essential for proper brain development.

Although the eating of fats today is believed by some to be a cause of heart disease (erroneously, see The Cholesterol Myth ), we know that our ancestors ate large amounts of fat. Animal skulls are broken open and the brains scooped out; long bones likewise are broken for their marrow content. Both brain and marrow are very rich in fat.

This is interesting. I don't have a direct reply to this. I will find do some research and come back to it later.

Toxicity of raw vegetables

The second investigation (10) concerned the inedibility of many of today's plant foods in the raw state which contain many anti-nutrients that can damage a wide variety of human physiological systems. These antinutrients include alkylrescorcinols, alpha-amylase inhitors, protease inhibitors, etc. These must be broken down by cooking, and cooking for a long time, before they can be eaten safely. Beans and other legumes although rich in both carbohydrate and protein, also contain protease inhibitors. Starchy roots - yams and cassava - are common staples today, but if not well cooked are very toxic indeed. The cassava even contains cyanide which must be oxidised by heat to make it safe to eat. And apart from the anti-nutrients above, the starch in cereals - wheat, rice, barley, oats, and rye - are also inedible in quantity if not cooked first. Cooking causes the starch granules in the flour to swell and be disrupted by a process called gelatinization Without this the starch much less accessible to digestion by pancreatic amylase. (11) (See also soybeans below.) Unlike meat, which can be easily digested in its raw state, vegetables should really never be eaten raw and cereals should be fermented and then cooked for a very long time before being eaten to neutralise the phytic acid and other toxic anti-nutrients. That fact that we don't do these things is the reason for so much atopic disease - asthma, eczema, and so on - around today.

The fact that some raw vegetables are toxic doesn't mean we can't be vegetarians. I can't believe what nonsense is brought up sometimes in such articles. I am by no means an advocate of eating toxic vegetables.

'Homo carnivorus'

There is no doubt whatsoever that we cannot be a vegetarian species. From at least the time that Homo erectus appeared in the cold Eurasian continent some 500,000 years ago, we must have lived on and adapted to a diet almost exclusively of meat.

All this evidence points to our being pure carnivores, as are the big cats. However, we are a remarkably successful species. It is unlikely that we would have been quite so successful if we had been forced to rely on only one source of food. It is obvious from archaeological remains that we tended to be more opportunist eaters. We hunted and ate meat primarily but, if meat was in short supply, we would eat almost anything - so long as it did not require cooking. This still precluded some of the roots and most of the legumes and cereals that we eat today. When meat was in short supply, we got our protein from nuts and ate fruits and berries. During our evolution, therefore, when we lived well, our diet was high in protein and fat: during lean times it was richer in carbohydrates.

So, our ideal diet, the one we evolved and adapted to, must also be one which is high in proteins and fats, and low in carbohydrates.

There is one further piece of evidence that really confirms this. That is the design of our digestive organs and digestive enzymes, which are exactly like those of the great carnivores - and nothing at all like those of a herbivore. Click here for that comparison.

The fact that we lived on meat for quite a while doesn't mean we have evolutionary adapted to it.

 

[Dirk]

Re: Questions

Dirk, it also makes sense to view all this in terms of goals and aims. When you refer to biological evolution, the point is just to make sure the organism survives to reproduction (understanding "reproduction" in human terms means some upbringing of children and maybe even some grandparenting). So yes, humans evolved as omnivores, not carnivores, but our aim in this very unique time of cataclysm is necessarily different. In other words we are looking to optimize nutrition to survive extreme stress in order to achieve an AIM.

That's a different story. Especially when you take the suppression of the PTB and the earth changes into account it may be wiser to eat a diet that is different than the one that is evolutionary optimal.

 

[Nienna]

Re: Questions

Dirk, you say the articles suggested are flawed. What is your criteria for them being flawed? Can you please give references?

 

[Dirk]

Re: Questions

Dirk, you say the articles suggested are flawed. What is your criteria for them being flawed? Can you please give references?

I have elaborated on it?

Though, one good reference is the "80/10/10 Diet" by Douglas Graham.

 

[Gaby]

Re: Questions

I think you are suffering from misinfo. Read:
Burying The Vegetarian Hypothesis

Just commented on that. Highly flawed article as stated above.

The Naive Vegetarian

Flawed article too.

Just because you say an article is flawed doesn't make it so. For instance, your explanations come across as merely guesses and speculations. Don't you want to share more about your points of view and research for the sake of discussion?

 

[Laura]

Re: Questions

I think you are suffering from misinfo. Read:
Burying The Vegetarian Hypothesis

Just commented on that. Highly flawed article as stated above.

The Naive Vegetarian

Flawed article too.

Just because you say an article is flawed doesn't make it so. For instance, your explanations come across as merely guesses and speculations. Don't you want to share more about your points of view and research for the sake of discussion?

Indeed. The author of the article did a LOT of research and so did others on our team, checking and cross-checking the available scientific literature. We don't think it is flawed at all. And that is not just opinion, it is based on a lot of evidence AND practical experience from experimentation.

 

[Dirk]

Re: Questions

Just because you say an article is flawed doesn't make it so.
For instance, your explanations come across as merely guesses and speculations. Don't you want to share more about your points of view and research for the sake of discussion?

Psyche, what, in my arguments comes across as guesses and speculations?

I read the articles that are recommended here and what I find is a bunch of inconsistencies in the articles and illogical conclusions.

About: Burying The Vegetarian Hypothesis. Main point of the article:

Inconsistencies:

1. The articles claims that the MBR scales linearly with mass. This is not the case. It scales with the power of between 3/4 and 2/3. Anyway, just stated for completion purposes, since this is unimportant for the argument, but it shows something about the quality of the article. ( see http://en.wikipedia.org/wiki/Kleiber's_law )
2. The article treats Kleiber's law as a physical law. This is not the case. It is a fit of emperical data and individual cases can (and actually DO) deviate from this fit.

Then the writer articles uses this argument:

Total BMR = brain BMR + heart BMR + kidney BMR + GI tract BMR + liver BMR + the remainder of the body's tissues

and since the brain BMR in a human is higher than in another species, and since heart, kidney and liver BMR in a 65kg human are approximately the same as in a 65kg primate and the remainder of body tissues are unimportant the writer concludes the BMR of the GI tract in a human must be lower than in a primate.

If it was a physical law Total BMR 65kg monkey should be equal to Total BMR of a 65kg human. As stated in inconsistency 2 this isn't the case.

Well, anyway, let's suppose that the deviations are actually small (unfortunately they don't give the actual numbers) and that they DO have a point. That the increase in BMR of the brain actually does result in a decrease of BMR of the GI tract.

And then they just conclude:

t doesn't matter what the driving reason is for increasing brain size, it corresponded to an equal decreasing in the size of the gut. And in order to still be able to extract enough nutrition given a smaller gut-size, a higher quality food source was necessary - meat. Increasing the amount of easily-extracted energy source from animal foods allowed us to maintain our total metabolic rate while our guts shrank and our brains grew.

Gut size becomes smaller so a higher quality food source was necessary. MEAT!

What the hell????

Sorry, I really cannot follow that step.

It costs the body much less energy to extract energy from ripe fruits (the fructose and glucose can readily and directly be absorbed) than from meat (where the protein and fats need to be converted into sugars in order to be utilisable for the body as an energy source). So, in my opinion this is an excellent argument for fruitarianism with the addition of leafy greens for adequate mineral supply. Again, it also implies that grains, soy and a whole bunch of other vegetarian foods are indeed not the way to go, because they are to heavy on our GI tract.

Then this:

We can see that, compared to humans, chimps and gorillas have large protruding bellies that hold in their larger GI tract.

Chimps and gorillas eat bark as part of their diet. Luckily that is not on my menu, but I can imagine that a serious GI tract is necessary for digestion of such foods.

Does this clarify?