149 replies to this topic

[JLL]

The majority of people probably wouldn't fit into the "gluten intolerant" category, but many people who have eaten grains for decades suddenly feel better when they stop eating them. Doesn't this suggest that we aren't fully adapted to eating grains?

[Blue]

The majority of people probably wouldn't fit into the "gluten intolerant" category, but many people who have eaten grains for decades suddenly feel better when they stop eating them. Doesn't this suggest that we aren't fully adapted to eating grains?

Many people "feel better" from homeopathic preparations. Just look at iHerb product recommendations. Does not prove it works. Can you cite a study showing less inflammation or any other improvements from removing grain from the diet?

[JLL]

The majority of people probably wouldn't fit into the "gluten intolerant" category, but many people who have eaten grains for decades suddenly feel better when they stop eating them. Doesn't this suggest that we aren't fully adapted to eating grains?

Many people "feel better" from homeopathic preparations. Just look at iHerb product recommendations. Does not prove it works. Can you cite a study showing less inflammation or any other improvements from removing grain from the diet?

Stephan discusses some on his blog: http://wholehealthso.....eolithic diet

But that's all I could find. Everything I could find on pubmed was done on patients with celiac disease.

[Blue]

Why use pubmed when Google Scholar is much better?
http://www.imminst.o...lar-t32996.html

Regarding the study mentioned in the blog it was not a gluten vs. non-gluten study in the healthy, with other factors unchanged, which would be what could say anything. So many differences between the diets in the blog study that impossible to say that reduced gluten was responsible for anything. Regarding the results, CR again raises its head. The paleolithic diet should be given credit for reducing calorie intake but unclear if there was any benefit to it not arising from the CR.

[Skötkonung]

Other species clearly different from us in many ways are not interesting. Gluten intolerance does not "run rampant", even if paleo dieters for ideological reasons like to think so. Almost all people can eat wheat without problems.

...

You have furthermore argued that evolution have not had the time to adapt to recent diet changes. That is clearly wrong for example for lactose intolerance where a tolerance has occurred in populations having a diet including a lot of milk from cows.

There is a large difference between a mild intolerance and celiac's disease. Regarding your comparison to lactose, it should be mentioned the lactose intolerance affects a very large portion of the world:

http://en.wikipedia....erance_by_group

Italians, who one might think of as being very familiar with milk consumption, have upwards of 50% intolerance. Again, demonstrating an insufficient amount of time to become fully adapted to these new foods.

Regarding you isotope study. The diet of the Neanderthals is not relevant, again, very different from ourselves. Regrding the method itself: "Isotopic analysis provides information about the sources of dietary protein over a number of years, even though it does not measure the caloric contributions of different foods. As the method only measures protein intake, many low-protein foods that may have been important to the diet (i.e., high caloric foods like honey, underground storage organs, and essential mineral and vitamin rich plant foods) are simply invisible to this method."

Now this study argues that in Europe 40,000 to 27,000 years ago most of the protein came from animal sources. That does not prove that diet was ketogenic. Furthermore, does not say anything of the time outside this period. Human are very good predators that have often when made many other species extinct when they move into a new area. Like many species made quickly extinct in the Americas when humans moved in. So this time period may only have been a brief period of feast when homo sapiens sapiens sapiens moved into Europe and hunted down all the big game animals. Furthermore, the study says nothing regarding the situation outside Europe.

Do you have any reason to believe paleolithic humans would be living differently outside of Europe? Such as in Asia, Mesopotamia, or Africa? Furthermore, apparently you missed the "early modern humans" part of the title, because that study does address homo sapiens sapiens. And finally, I would argue that comparing neanderthal biology to human biology, specifically regarding nutrition, is probably superior to comparing a rodent to a human. The reasoning here should be obvious.

You also forget that all foods contain proteins, especially vegetables, seeds, nuts, and fruits. One can extrapolate caloric and macronutrient data using current foods that match isotope signatures from ancient humans and hominids. For instance, if we see a 10:1 ratio of chicken (high protein food) to broccoli (low protein food) isotopes in a hominid's bones, we can then deduce the total dietary composition.

Broccoli Raw (per 1g protein):
- 10.3 calories
- 0g fat
- 2g carbohydrate

Rotisserie Chicken (per 1g protein):
- 8.5 calories
- .5g fat
- 0 g carbohydrate

Because these individuals show a high amount of animal food isotopes, lets assume a sample protein intake was maybe 200g. That means they consumed roughly 180g of that protein from chicken, and roughly 18g from broccoli.

This means, such as diet would have been roughly:
- 1,715.4 calories
- 36g carbohydrate
- 90g fat
- 200g protein

This would clearly indicate that these individuals live in ketosis most if not all of the time.

See how deductive reasoning can be used to approximate nutritional values of ancient peoples using isotopic evidence? Sure this is a gross over-simplification and of course there are more accurate ways to estimate quantity of protein consumed. Also, as mentioned in the study, because this type of investigation measures only bulk protein consumption over a number of years, less commonly consumed foods (such as medicinal plants) may be overlooked. But for all intensive purposes, these methods allow us to reasonably deduce what these people may have eaten and in what quantities. Finally, unlike bone, tooth dentin does not alter over a lifetime, and therefore it reflects a specific period of time of formation. Therefore, the isotopic data from a Neanderthal premolar does not reflect a lifetime average, but instead the diet at the ages of later childhood/early adolescence.

Regarding a ketogenic diet, those advocating that there are benefits should cite the evidence. There seem to be no animal studies showing that it increases lifespan in any species. Since animal studies using a ketogenic diet have often included CR it is unclear what benefits a ketogenic diet, if any, provides. If there is no clear evidence of benefits, then there is no reason to advocate it.

I have not said that a ketogenic diet is best for longevity, I have only indicated that it likely lowers IGF-1, through process which I have already explained. You apparently disagree, but have yet to critique the processes that I have described. If you have doubts regarding these specific processes, I suggest you do some research.

Here is a study to get you started:
http://diabetes.diab...8/1816.abstract

Edited by Skotkonung, 05 October 2009 - 08:31 PM.

[TheFountain]

There is no definitive evidence that a high-fat Paleo diet is better than a vegetarian moderate fat, low protein diet for anything, including immediate health. All there is is correlative evidence, but there is plenty of correlative evidence with regard to vegetarian low protein diets too. So my question to Paleo advocators is this. Why is correlation enough for your diet to be proven the best but not for mine? I mean I don't get your reasoning here.

You complain that any studies showing vegetarian diets are poorly constructed and leave out certain factors. But the dietary studies (most of which aren't on humans) leave much to be desired as well. Not to mention the fact that they don't correct for many imbalances in the participants chosen for the vegetariian controls (such as the fact that they may consume bad carbs or extremely high fructose diets).

Please give a logical answer why you think there is ample evidence for high fat paleo diets. There is basically Atkins, a book by Gary Taubes and advocation by Dr. Eades and Weils and a few correlative studies. This amounts to about 5% of a viewpoint versus 95% of the viewpoint that high fat diets are bad for both current health and longevity. Why should one believe the 5% minority position over the established 95% position of the medical community?

I am not advocating the popular view I am just letting you know that many people will have a hard time accepting the minority position and you need to give them solid evidence they should. As far as I am concerned that solid evidence has not been presented. Just vague Isotope studies and correlation. For example when I discuss this with family members and say 'well maybe high fat diets are not such a bad thing' and they say 'where did you hear that' what studies should I point to for their own reference? And what should I tell those family and friends whose doctors repeatedly remind them that high fat=bad that the doctors themselves are uneducated idiots?

Furthermore why believe people on a web forum with the time on their hands to make these inconclusive connections and not a trained nutritionist? Not that my family or friends advocate my diet either, but I believe there is at least a little more acceptance in society that vegetarian diets are healthier than the current western diet than there is that an obscure paleolithic diet is better than same. We need solid evidence of all these blurry claims about the Paleo diet. All I am seeing is alot of blog entries, advocations and a book by someone (Gary Taubes) who is not even trained in the field.

Edited by TheFountain, 05 October 2009 - 09:13 PM.

[Skötkonung]

I am not advocating the popular view I am just letting you know that many people will have a hard time accepting the minority position and you need to give them solid evidence they should. As far as I am concerned that solid evidence has not been presented. Just vague Isotope studies and correlation. For example when I discuss this with family members and say 'well maybe high fat diets are not such a bad thing' and they say 'where did you hear that' what studies should I point to for their own reference? And what should I tell those family and friends whose doctors repeatedly remind them that high fat=bad that the doctors themselves are uneducated idiots? furthermore why believe people on a web forum with the time on their hands to make these inconclusive connections and not a trained nutritionist?

Some people would say that there is no true reality, only perceptions and opinions. Others would argue that there must be some absolute reality or truth. One view says that there are no absolutes that define reality. Those who hold this view believe everything is relative to something else, and thus there can be no actual reality. Because of that, there are ultimately no moral absolutes, no authority for deciding if an action is positive or negative, right or wrong. This view leads to "situational ethics," the belief that what is right or wrong is relative to the situation. There is no right or wrong; therefore, whatever feels or seems right at the time and in that situation is right. Of course, situational ethics leads to a subjective, "whatever feels good" mentality and lifestyle, which can have profoundly devastating or beneficial effect on society and individuals. This is postmodernism, creating a society that regards all values, beliefs, lifestyles, and truth claims as equally valid.

Having spent much time reading Eades, Taubes, T. Campbell, McDonald, Cordain, Sears, Kendrick, Ravnskov, and others, I have come to the conclusion that this is likely the case regarding human nutrition. The physical body is a complex machine and how we feed and maintain it will vary significantly depending on the results we are trying to achieve. Here in lies the problem: For me, what quantifies a superior diet is one that maximizes the cross-section between physical performance / prowess and longevity. For others, it may be longevity, even if that sacrifices physical performance (as is the case with caloric restriction). There are some (such as professional athletes) who are so obsessed with their craft or sport that they would die young to win a few games. And certainly more than a few people augment their diet for ethical or religious purposes. We are all looking for different things and there in lies the disconnect that consumes much of the discourse on this forum.

Because there is no such thing as a perfect study, nor is there a definitive answer for nutrition, we must be agnostic. However, even agnosticism can be weighted.

Based on all of the literature I have read and my understanding of human physiology, I have come to the conclusion that a high fat diet is not bad for longevity, and may even be beneficial. I believe it is especially beneficial in the context of my nutritional goals. Others will likely have different opinions based on their understanding of the human body and their exposure to current medical literature. The only way to have security in your diet is to have security in your understanding, both of how the body functions and what you hope to achieve from it. The more you know about these two items, the more you will feel comfortable with your opinion. If you cannot honestly say that you have read all the literature or understand the primary mechanisms by which the body works, then you cannot be certain in your nutrition decisions.

As medical science continues to progress, some day I may find I am pursuing my nutritional goals incorrectly, and if I am, I will deal with the penalty when it comes. However, for the time being, I have never felt better in terms of my own health and performance, and I have accomplished it all through nutritional augmentation. If I only live to 100 instead of 110, so be it.

EDIT
Remember, doctors are people too and just because they have an advanced degree, does not make them superior to you. As a doctorate candidate (nothing related to biology or nutritional sciences) I learned first hand that even people with advanced or multiple degrees can be wrong or ignorant.

[TheFountain]

Based on all of the literature I have read and my understanding of human physiology, I have come to the conclusion that a high fat diet is not bad for longevity, and may even be beneficial. I believe it is especially beneficial in the context of my nutritional goals. Others will likely have different opinions based on their understanding of the human body and their exposure to current medical literature.

That is what I am asking. What makes people like you, Duke and other's advocating this diet better sources than actual MDs and other's with either degrees or who are well studied in nutrition? I have read a bit of extracurricular literature while attending college myself, does that mean I am a valid source? No. What are your credentials is what I am asking.

The only way to have security in your diet is to have security in your understanding, both of how the body functions and what you hope to achieve from it. The more you know about these two items, the more you will feel comfortable with your opinion. If you cannot honestly say that you have read all the literature or understand the primary mechanisms by which the body works, then you cannot be certain in your nutrition decisions.

Are you telling me that you have read every bit of medical literature out there? Even if you answer with a hypothetical yes, do you think we even know 20% of all we need to in order to make accurate choices?

As a doctorate candidate

More like a super -human. I swear sometimes you strike me as a robot created in a laboratory. I don't mean that as an insult. It's just where do you find the time to be a body builder, a doctorate candidate, have a job and amass all these studies (that you just seem to pull out of a magic hat) with which to argue endlessly on this forum? Unless you sleep like 1 hour a night.

Edited by TheFountain, 05 October 2009 - 10:43 PM.

[Skötkonung]

That is what I am asking. What makes people like you, Duke and other's advocating this diet better sources than actual MDs and other's with either degrees or who are well studied in nutrition? I have read a bit of extracurricular literature while attending college myself, does that mean I am a valid source? No. What are your credentials is what I am asking.

I have no health credentials. I developed my opinions from continually reading both sides of the nutrition "debate." A better question would be, what makes Dr Weil or Dr Pritikin better than Dr Atkins or Dr Eades? Did you ever read "The Protein Debate" between T. Campbell and Loren Cordain? After you read it, did you have a opinion on who was right and who was wrong? That's what I do, and the more I have read, the more these opinion are ingrained.

Are you telling me that you have read every bit of medical literature out there? Even if you answer with a hypothetical yes, do you think we even know 20% of all we need to in order to make accurate choices?

No, I have not read everything, nor do I have enough time or ambition to read everything regarding health and nutrition. Could I be wrong? Sure. Am I wrong about some things? Probably. However, I have read enough to feel comfortable expressing my opinions and applying them to my own circumstance.

More like a super -human. I swear sometimes you strike me as a robot created in a laboratory. I don't mean that as an insult. It's just where do you find the time to be a body builder, a doctorate candidate, have a job and amass all these studies (that you just seem to pull out of a magic hat) with which to argue endlessly on this forum? Unless you sleep like 1 hour a night.

My job and my graduate studies are analogous. After getting my masters degree from Portland State University, I now work full time for the Nohad A Toulan School of Urban Studies and Planning. A perk of the job is spending many hours at or near a computer (note that I rarely post comments outside of regular business hours). The work I am doing with the university involves research towards my ph.d thesis as well as other responsibilities. When work is prioritized correctly, I probably work no more than 50hrs a week, which leaves plenty of time for bodybuilding and other extracurricular activities. I don't think my situation is unusual, I will be 27 on the 8th. By this age, many people have achieved much more than I - for instance, my girlfriend has got her masters degree at age 22 from George Fox University - two years ahead of me. My friend Andrey from the Ukraine (who is studying at Oregon Health and Science University) will have his phd completed this year and he is 26. My degree will not be completed for another two years, and I have yet to achieve any relevant experience working in private industry.

By the way, if it makes you feel better, I don't have many friends

Edited by Skotkonung, 05 October 2009 - 11:34 PM.

[Blue]

Other species clearly different from us in many ways are not interesting. Gluten intolerance does not "run rampant", even if paleo dieters for ideological reasons like to think so. Almost all people can eat wheat without problems.

...

You have furthermore argued that evolution have not had the time to adapt to recent diet changes. That is clearly wrong for example for lactose intolerance where a tolerance has occurred in populations having a diet including a lot of milk from cows.

There is a large difference between a mild intolerance and celiac's disease. Regarding your comparison to lactose, it should be mentioned the lactose intolerance affects a very large portion of the world:

http://en.wikipedia....erance_by_group

Italians, who one might think of as being very familiar with milk consumption, have upwards of 50% intolerance. Again, demonstrating an insufficient amount of time to become fully adapted to these new foods.

Regarding you isotope study. The diet of the Neanderthals is not relevant, again, very different from ourselves. Regrding the method itself: "Isotopic analysis provides information about the sources of dietary protein over a number of years, even though it does not measure the caloric contributions of different foods. As the method only measures protein intake, many low-protein foods that may have been important to the diet (i.e., high caloric foods like honey, underground storage organs, and essential mineral and vitamin rich plant foods) are simply invisible to this method."

Now this study argues that in Europe 40,000 to 27,000 years ago most of the protein came from animal sources. That does not prove that diet was ketogenic. Furthermore, does not say anything of the time outside this period. Human are very good predators that have often when made many other species extinct when they move into a new area. Like many species made quickly extinct in the Americas when humans moved in. So this time period may only have been a brief period of feast when homo sapiens sapiens sapiens moved into Europe and hunted down all the big game animals. Furthermore, the study says nothing regarding the situation outside Europe.

Do you have any reason to believe paleolithic humans would be living differently outside of Europe? Such as in Asia, Mesopotamia, or Africa? Furthermore, apparently you missed the "early modern humans" part of the title, because that study does address homo sapiens sapiens. And finally, I would argue that comparing neanderthal biology to human biology, specifically regarding nutrition, is probably superior to comparing a rodent to a human. The reasoning here should be obvious.

You also forget that all foods contain proteins, especially vegetables, seeds, nuts, and fruits. One can extrapolate caloric and macronutrient data using current foods that match isotope signatures from ancient humans and hominids. For instance, if we see a 10:1 ratio of chicken (high protein food) to broccoli (low protein food) isotopes in a hominid's bones, we can then deduce the total dietary composition.

Broccoli Raw (per 1g protein):
- 10.3 calories
- 0g fat
- 2g carbohydrate

Rotisserie Chicken (per 1g protein):
- 8.5 calories
- .5g fat
- 0 g carbohydrate

Because these individuals show a high amount of animal food isotopes, lets assume a sample protein intake was maybe 200g. That means they consumed roughly 180g of that protein from chicken, and roughly 18g from broccoli.

This means, such as diet would have been roughly:
- 1,715.4 calories
- 36g carbohydrate
- 90g fat
- 200g protein

This would clearly indicate that these individuals live in ketosis most if not all of the time.

See how deductive reasoning can be used to approximate nutritional values of ancient peoples using isotopic evidence? Sure this is a gross over-simplification and of course there are more accurate ways to estimate quantity of protein consumed. Also, as mentioned in the study, because this type of investigation measures only bulk protein consumption over a number of years, less commonly consumed foods (such as medicinal plants) may be overlooked. But for all intensive purposes, these methods allow us to reasonably deduce what these people may have eaten and in what quantities. Finally, unlike bone, tooth dentin does not alter over a lifetime, and therefore it reflects a specific period of time of formation. Therefore, the isotopic data from a Neanderthal premolar does not reflect a lifetime average, but instead the diet at the ages of later childhood/early adolescence.

Regarding a ketogenic diet, those advocating that there are benefits should cite the evidence. There seem to be no animal studies showing that it increases lifespan in any species. Since animal studies using a ketogenic diet have often included CR it is unclear what benefits a ketogenic diet, if any, provides. If there is no clear evidence of benefits, then there is no reason to advocate it.

I have not said that a ketogenic diet is best for longevity, I have only indicated that it likely lowers IGF-1, through process which I have already explained. You apparently disagree, but have yet to critique the processes that I have described. If you have doubts regarding these specific processes, I suggest you do some research.

Here is a study to get you started:
http://diabetes.diab...8/1816.abstract

Why should Italians have had pressure for developing milk tolerance? Their tradional source of fat is olive oil. Milk products is not a staple of the mediterranean diet. That there have developed regional differences in milk tolerance is clear evidence of quick adaption to local diet.

Yes, obviously paleolithic people would have a different diet if they had hunted the big game animals to extinction as compared to feasting on them.

If we include neanderthals, why not tree-living primates? Let us concentrate on the diet of our species.

No, you cannot claim that they had a ketogenic diet even if we agree that most of the protein intake was from animal sources. They may have had a lot of carbohydrates from sources such fruit and honey which have little protein. The article clearly states that the method cannot detect such intake. Furthermore, will even a superhigh protein diet induce ketosis? A ketogenic diet in studies is a superhigh fat diet, not a superhigh protein diet.

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

Edited by Blue, 05 October 2009 - 11:43 PM.

[Skötkonung]

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

The linked study says:
"An IGF-2/IGF-1 receptor autocrine loop operates in β-cells. GLP-1 increases its activity by augmenting IGF-1 receptor expression and by stimulating secretion; this mechanism is required for GLP-1–induced protection against apoptosis."

"The results suggest that glucagon-like peptide-1 may act as a growth factor for the beta cell by a phosphatidylinositol 3-kinase mediated event. Glucagon-like peptide-1 could also regulate the expression of the insulin gene and genes encoding enzymes implicated in glucose transport and metabolism through the phosphatidylinositol 3-kinase/PDX-1 transduction signalling pathway." [source]

Phosphoinositide 3-kinase is linked to the stimulation of IGF-1. But that is another discussion entirely.

Let's look at GLP-1:
Glucagon-like peptide-1 (GLP-1) increases insulin secretion from the pancreas in a glucose-dependent manner. GLP-1 is primarily stimulated by the ingestion of carbohydrate, and to a much lesser extant, lipid and protein.

"The main actions of GLP-1 are to stimulate insulin secretion (i.e., to act as an incretin hormone) and to inhibit glucagon secretion, thereby contributing to limit postprandial glucose excursions" [source]

After a carbohydrate containing meal, it is especially pertinent that insulin be secreted to control blood sugar. While this study was conducted in rodents, the mechanism works in the same way in humans:

"Dietary resistant starch upregulates total GLP-1 and PYY in a sustained day-long manner through fermentation in rodents." [source]

"Oral administration of glucose (50 g) induced a biphasic GLP-1 release peaking at 30-60 min and a biphasic GIP release peaking at 5 and 45 min. This increase paralleled the secretion of insulin." [source]

So if insulin activity parallels GLP-1 stimulation, what happens to insulin levels when the body is in ketosis? Insulin falls. In a condition called diabetic ketosis, sufferers have a chronic lack of insulin and their body is forced into ketosis.

Because of the above listed connections, we would expect a sufferer of diabetic ketosis (and more commonly, diabetes) to have low IGF-1:
"All study parameters except for serum phosphate levels behaved in parallel in both clinical conditions, and abnormalities disappeared with the correction of acidosis except for IGF-1, which remained low in diabetic subjects." [source]

"The more IGF-1 someone has, the higher their bone mineral density," ... "People with diabetes have low levels of IGF-1, and they often have low bone density." [source]

"In contrast, free IGF-1 concentrations (0.72 ± 0.22 ng/mL at baseline) were markedly suppressed during insulin withdrawal to values below the detection limit of the assay (0.08 ng/mL) in 15 of the 17 patients (P < 0.001)." [source]

Interestingly, supplemental GLP-1 is now being investigated as a treatment for diabetes to correct the aformentioned problems.

"The marked reduction in circulating free IGF-1 after insulin withdrawal and its increase after insulin administration suggest that acute changes in IGFBP concentrations induced by insulin are important regulators of IGF-1 bioavailability" [source]

Interestingly, this has implications on evolution:

"It is concluded that IGF-1 takes part in regulation of the carbohydrate metabolism already at early stages of evolution of vertebrates." [source]

These affects on carbohydrate metabolism are also seen in humans:

"A carbohydrate- rich drink given shortly before surgery increases IGF-I bioavailability post-operatively in patients undergoing a THR, but has no significant effects on body composition after 2 months in physically active people. We suggest that, if the operation is postponed for more than four hours on the same day, an additional carbohydrate drink should be given." [source]

Edited by Skotkonung, 06 October 2009 - 02:10 AM.

[Skötkonung]

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

"Specifically, insulin, insulin-like-growth factor-1 (IGF-1), and caloric intake, which can all be affected by diet, are important in prostate cancer biology. We tested the hypothesis that an isocaloric low-carbohydrate ketogenic diet (LCKD), which in humans lowers insulin and IGF-1 levels, would delay prostate cancer growth in a xenograft model." [source]

[Skötkonung]

Why should Italians have had pressure for developing milk tolerance? Their tradional source of fat is olive oil. Milk products is not a staple of the mediterranean diet. That there have developed regional differences in milk tolerance is clear evidence of quick adaption to local diet.

Yes, obviously paleolithic people would have a different diet if they had hunted the big game animals to extinction as compared to feasting on them.

If we include neanderthals, why not tree-living primates? Let us concentrate on the diet of our species.

Neanderthals are part of the same genus as homo sapiens sapiens. This genus is known as Homo. Primates are part of Pan. Neanderthals are the most similar species of the Homo genus in terms of genetics, physiology, culture and is known to have co-existed / co-habitated with Homo Sapiens Sapiens during the Pleistocene and Paleolithic. In regard to other species, they are the most like modern humans and can probably tell us more about our reaction to a certain macro-nutrient than any other species (especially rodent).

"Edward Rubin of the Lawrence Berkeley National Laboratory in Berkeley, California states that recent genome testing of Neanderthals suggests human and Neanderthal DNA are some 99.5% to nearly 99.9% identical." [source]

Regarding lactose intolerance, by your reasoning, Northern Europeans shouldn't have developed a tolerance for dairy because they can get plenty of fat from reindeer and other large mega fauna. Besides, don't the people of the middle east use plenty of dairy in their cooking? What about the Italians? Dairy was not absent from these people's foods either. In fact, the Roman breakfast called jentaculum normally consisted of salted bread, milk or wine, and perhaps dried fruit, eggs or cheese.

Edited by Skotkonung, 06 October 2009 - 03:20 AM.

[Blue]

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

"Specifically, insulin, insulin-like-growth factor-1 (IGF-1), and caloric intake, which can all be affected by diet, are important in prostate cancer biology. We tested the hypothesis that an isocaloric low-carbohydrate ketogenic diet (LCKD), which in humans lowers insulin and IGF-1 levels, would delay prostate cancer growth in a xenograft model." [source]

Unclear what this refers to. A high-fat ketogenic diet isocaloric to a high carbohydrate diet where both diets are CR diets reducing the previous weight of obese subjects as seems usually to be the case in human ketogenic diet studies?

[Blue]

Why should Italians have had pressure for developing milk tolerance? Their tradional source of fat is olive oil. Milk products is not a staple of the mediterranean diet. That there have developed regional differences in milk tolerance is clear evidence of quick adaption to local diet.

Yes, obviously paleolithic people would have a different diet if they had hunted the big game animals to extinction as compared to feasting on them.

If we include neanderthals, why not tree-living primates? Let us concentrate on the diet of our species.

Neanderthals are part of the same genus as homo sapiens sapiens. This genus is known as Homo. Primates are part of Pan. Neanderthals are the most similar species of the Homo genus in terms of genetics, physiology, culture and is known to have co-existed / co-habitated with Homo Sapiens Sapiens during the Pleistocene and Paleolithic. In regard to other species, they are the most like modern humans and can probably tell us more about our reaction to a certain macro-nutrient than any other species (especially rodent).

"Edward Rubin of the Lawrence Berkeley National Laboratory in Berkeley, California states that recent genome testing of Neanderthals suggests human and Neanderthal DNA are some 99.5% to nearly 99.9% identical." [source]

Regarding lactose intolerance, by your reasoning, Northern Europeans shouldn't have developed a tolerance for dairy because they can get plenty of fat from reindeer and other large mega fauna. Besides, don't the people of the middle east use plenty of dairy in their cooking? What about the Italians? Dairy was not absent from these people's foods either. In fact, the Roman breakfast called jentaculum normally consisted of salted bread, milk or wine, and perhaps dried fruit, eggs or cheese.

Neanderthals are clearly different from us many ways. Sure, they are more similar to us than now living primates and rats, but on the other hand we can study these species and the effect of diet directly. The diet and their effects on Neanderthals are just speculations.

Northern Europeans have used cattle as long as they have used agriculture so they have had a need to develop milk tolerance. Reindeers are only used by very small minority in the far north. Regarding the mediterranean counties, the mediterranean diet does not include much cow milk and what it does is in the form of cheese and tradional yoghurt which are not a problem regarding lactose.

I repeat my point a superhigh protein diet is likely not a ketogenic diet since the amino acids can be converted to glucose so there is less need for ketone bodies for the brain. When a ketogenic diet is attempted it is superhigh fat diets with protein and carbohydrates restricted for this reason.

I also repeat my point that you cannot know the paleolithic diet exactly. Even if we agree that (in Europe between 40,000-27,000 years ago) most of the protein intake was from animal sources. They may have had a lot of carbohydrates from sources such fruit and honey which have little protein. The earlier article clearly states that the isotope method cannot detect such intake.

Edited by Blue, 06 October 2009 - 04:08 AM.

[Skötkonung]

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

"Specifically, insulin, insulin-like-growth factor-1 (IGF-1), and caloric intake, which can all be affected by diet, are important in prostate cancer biology. We tested the hypothesis that an isocaloric low-carbohydrate ketogenic diet (LCKD), which in humans lowers insulin and IGF-1 levels, would delay prostate cancer growth in a xenograft model." [source]

Unclear what this refers to. A high-fat ketogenic diet isocaloric to a high carbohydrate diet where both diets are CR diets reducing the previous weight of obese subjects as seems usually to be the case in human ketogenic diet studies?

The researchers wanted to know if a ketogenic diet with normal caloric intake would lower IGF-1 levels sufficiently to slow prostate tumor growth.

[Blue]

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

"Specifically, insulin, insulin-like-growth factor-1 (IGF-1), and caloric intake, which can all be affected by diet, are important in prostate cancer biology. We tested the hypothesis that an isocaloric low-carbohydrate ketogenic diet (LCKD), which in humans lowers insulin and IGF-1 levels, would delay prostate cancer growth in a xenograft model." [source]

Unclear what this refers to. A high-fat ketogenic diet isocaloric to a high carbohydrate diet where both diets are CR diets reducing the previous weight of obese subjects as seems usually to be the case in human ketogenic diet studies?

The researchers wanted to know if a ketogenic diet with normal caloric intake would lower IGF-1 levels sufficiently to slow prostate tumor growth.

Yes, but the study was a rodent study. Their passing remark regarding the human isocaloric low-carbohydrate ketogenic diet must refer to some other study.

[Skötkonung]

I also repeat my point that you cannot know the paleolithic diet exactly. Even if we agree that (in Europe between 40,000-27,000 years ago) most of the protein intake was from animal sources. They may have had a lot of carbohydrates from sources such fruit and honey which have little protein. The earlier article clearly states that the isotope method cannot detect such intake.

Aren't both fruit and honey available seasonally? What do you think these people were eating during the winter months? Particularly the long winter months of a protracted ice age winter. And please clarify for me why isotope studies can't detect fruit proteins while other plant proteins can be detected easily? It seems to me that if the food was undetectable by isotope studies, it would not have been a major contributor to ancient people's caloric intake. Even if ancient humans and their ancestors were in ketosis for 6 months of the year, that would still be significant enough to play a role in the evolutionary development of our carbohydrate metabolism.

[Skötkonung]

You have still not produced any study showing that a ketogenic diet without CR reduces IGF-1. Theoretical speculations are interesting but prove nothing. The study you mention does not mention a ketogenic diet.

"Specifically, insulin, insulin-like-growth factor-1 (IGF-1), and caloric intake, which can all be affected by diet, are important in prostate cancer biology. We tested the hypothesis that an isocaloric low-carbohydrate ketogenic diet (LCKD), which in humans lowers insulin and IGF-1 levels, would delay prostate cancer growth in a xenograft model." [source]

Unclear what this refers to. A high-fat ketogenic diet isocaloric to a high carbohydrate diet where both diets are CR diets reducing the previous weight of obese subjects as seems usually to be the case in human ketogenic diet studies?

The researchers wanted to know if a ketogenic diet with normal caloric intake would lower IGF-1 levels sufficiently to slow prostate tumor growth.

Yes, but the study was a rodent study. Their passing remark regarding the human isocaloric low-carbohydrate ketogenic diet must refer to some other study.

Yes, they acknowledged the effect in humans (likely referring to another study) and then proceeded to test their hypothesis in mice. The researchers used three sample diets: low-fat (12% kcal from fat), high-fat (40% kcal from fat), or a LCKD (85% kcal from fat, 0% kcal from carbohydrates).

Mice were fed on a modified paired feeding protocol to maintain equal calories among the groups. Mice fed the LCKD, despite initially consuming equal calories, lost significant amounts of weight (up to 15% of body weight) relative to the low-fat and high-fat fed mice. Mice on the LCKD were then fed extra calories to prevent further weight loss and to increase body weight to the weight among the other dietary groups. Mice fed the LCKD had significantly longer survival than mice fed a high-fat diet (log-rank, p=0.008).

This is what I find interesting:
There was trend for longer survival among men fed the LCKD relative to a low-fat diet (log-rank, p=0.06), but this did not reach statistical significance.

I wonder if they are referring to the same previous study?

[tunt01]

By the way, if it makes you feel better, I don't have many friends

i been reading this thread and the other diet debate threads, i really enjoy them.

this post made me laugh, thx for the

[Sillewater]

Great thread guys. I've learned so much from you Skotkonung!

[JLL]

What about this one:

http://www.clinexprh...pdf/6FRASER.PDF

Participants on a 7-day ketogenic diet (less than 40 grams of carbs per day, 0.8 g protein / kg body weight), eating 2000-2500 kcal (no CR), weighing around 60-65 kg. Baseline IGF-1 is 16.6, after a week of ketogenic diet it's 9.0.

The other papers I looked at concluded that high protein intake raises IGF-1 and high fat intake less so. Apparently ketosis counters some of this, at least for the first week. After getting used to ketones, maybe it's a different story.

[Blue]

I also repeat my point that you cannot know the paleolithic diet exactly. Even if we agree that (in Europe between 40,000-27,000 years ago) most of the protein intake was from animal sources. They may have had a lot of carbohydrates from sources such fruit and honey which have little protein. The earlier article clearly states that the isotope method cannot detect such intake.

Aren't both fruit and honey available seasonally? What do you think these people were eating during the winter months? Particularly the long winter months of a protracted ice age winter. And please clarify for me why isotope studies can't detect fruit proteins while other plant proteins can be detected easily? It seems to me that if the food was undetectable by isotope studies, it would not have been a major contributor to ancient people's caloric intake. Even if ancient humans and their ancestors were in ketosis for 6 months of the year, that would still be significant enough to play a role in the evolutionary development of our carbohydrate metabolism.

500 g blueberries = 72 g carbohydrates but just 3.7 g protein. Will be a minor protein addition undetected by the isotope method if added to the 200g meat protein diet in your example.

You are arguing that these people were similar to Inuits living in constant very coldregions? I see them more are as following the big game animals which likely migrated substantially to warmer regions in the winter.

Even assuming they ate meat exclusively during the winter, does this really cause ketosis? I repeat my point a superhigh protein diet is likely not a ketogenic diet since the amino acids can be converted to glucose so there is less need for ketone bodies for the brain. When a ketogenic diet is attempted it is superhigh fat diets with protein and carbohydrates restricted for this reason.

I take it you agree, since you have not responded, to my point that relatively short-term changes in diet such as the introduction of milk products for northern Eropeans can cause evolutionary adaptions. Thus, must also look at the diet and evolutionary adaptions to it in the last 10,000 years.

[Blue]

This is what I find interesting:
There was trend for longer survival among men fed the LCKD relative to a low-fat diet (log-rank, p=0.06), but this did not reach statistical significance.

I wonder if they are referring to the same previous study?

Seems likely taken the context that "men" should be "mice". Even abstracts may contain spelling mistakes.

[Blue]

What about this one:

http://www.clinexprh...pdf/6FRASER.PDF

Participants on a 7-day ketogenic diet (less than 40 grams of carbs per day, 0.8 g protein / kg body weight), eating 2000-2500 kcal (no CR), weighing around 60-65 kg. Baseline IGF-1 is 16.6, after a week of ketogenic diet it's 9.0.

The other papers I looked at concluded that high protein intake raises IGF-1 and high fat intake less so. Apparently ketosis counters some of this, at least for the first week. After getting used to ketones, maybe it's a different story.

Unclear what their kcal intake was before the study, even if their BMI was not very high (22-28), so not clear if there were a relative CR to their normal diet. They has a substantial weight reduction of 2.9 kg during the 1 week study. Likely restricted protein intake compared to their normal diet but again we do not know. This was a a true ketogenic diet with superhigh fat intake and low protein and carbohydrate intake. The ketone bodies were greatly increased.

Intersting, but I would really like to see the effect during a more long term study when the metabolism and weight had had some time to be stabilize to the new diet.

"In summary, using a ketogenic diet we
have found metabolic and hormonal ad-
aptations to carbohydrate restriction do
not induce clinical improvements or im-
munomodulatory changes in RA pa-
tients."

One week is far to short a time to make this statement. Give it some time on a stable weight.

Edited by Blue, 06 October 2009 - 10:06 PM.

[Skötkonung]

500 g blueberries = 72 g carbohydrates but just 3.7 g protein. Will be a minor protein addition undetected by the isotope method if added to the 200g meat protein diet in your example.

You are arguing that these people were similar to Inuits living in constant very coldregions? I see them more are as following the big game animals which likely migrated substantially to warmer regions in the winter.

Even assuming they ate meat exclusively during the winter, does this really cause ketosis? I repeat my point a superhigh protein diet is likely not a ketogenic diet since the amino acids can be converted to glucose so there is less need for ketone bodies for the brain. When a ketogenic diet is attempted it is superhigh fat diets with protein and carbohydrates restricted for this reason.

I take it you agree, since you have not responded, to my point that relatively short-term changes in diet such as the introduction of milk products for northern Eropeans can cause evolutionary adaptions. Thus, must also look at the diet and evolutionary adaptions to it in the last 10,000 years.

I understand your point about not being a significant contributor to total protein intake. However, if these people were regularly achieving a medium to high intake of blueberries (or other wild berries which are only seasonally available unless they dried and stored them), I would expect a long term accumulation of these trace proteins that would show in isotope studies. If they were eating them so infrequently or in such small amounts that they do not show in isotope studies, I have a hard time believing they would contribute significantly to their macro-nutrient ratio.

From the aformentioned study:
"Therefore, by comparing the isotope values of omnivores such as humans to the isotope values of herbivores and carnivores from the same site or region, we can determine whether they obtained their proteins from mainly animal sources (carnivore-like) or plant sources (herbivore-like), or a mix of both. The same process applies in aquatic (freshwater and marine) ecosystems. However, as there are often many more steps in the food chain in aquatic ecosystems, top-level aquatic consumers often have much higher δ¹⁵N values [i.e., seals have δ¹⁵N values of 18 to 20‰ (26)] than their terrestrial counterparts [i.e., wolves generally have values between 10 and 12‰ (9)]."

This is what the researchers found:
"Each Neanderthal had δ¹⁵N values that were 3 to 5‰ higher than contemporary herbivores and similar to carnivores (or in some cases slightly higher). In each study, the authors concluded that Neanderthals were top-level carnivores and that their main protein source was large herbivores."

And:

"Although the Neanderthals that have been studied to date come from different regions of Europe and time periods, the isotopic data show that, in each case, they have δ¹⁵N values between ≈3 and 5‰ higher than the local herbivores, and plot close to carnivores from the same or nearby sites. These higher δ¹⁵N values indicate that European Neanderthals had similar dietary adaptations. "

This is interesting to me because it indicates that Neanderthals might have consumed a predominantly (or almost exclusively) animal based diet. But what about humans?

"Early modern humans in Europe have a more varied range of isotopic values that indicates that some of them consumed significant quantities of aquatic foods, both from freshwater and marine sources. The only human contemporary with the Neanderthals that currently provides isotopic data, Oase 1, has δ¹⁵N values that are the highest of all of the modern humans and higher than all of the Neanderthal values."

Because humans regularly buried their dead, it was difficult to find herbivore and carnivore specimens in which to compare isotope ratios. However, in one instance where a neanderthal was directly comparable to a paleolithic human, it was demonstrated that this individual consumed more animal protein.

I understand your argument to be that a diet rich in animal meat would not provide enough fat to be ketogenic. However, you are making the assumption that all wild animals are inherently lean (like chicken) and that they did not consume the internal organs and marrow. However, as Stefansson noted when living with the Inuit, too much protein without fat and or carbohydrate causes sickness. This sickness was called "rabbit starvation," a sickness he had seen among Native Americans when they were forced to live on the relatively low-fat meat of rabbits. Despite this observation, researchers later decided to start a nutrition experiment by asking Stefansson to eat only lean meat. Within two days he was suffering from diarrhoea, nausea and weakness. He recovered when he added fat to his diet, in the form of calves brains fried in bacon grease.

Stefansson mentions in his book, Not By Bread Alone, how the Inuit preferred the kidneys, heart intestinal fat and, especially, marrow. It seems likely that the paleolithic humans and neanderthals would have also known to favor these foods as well.

That said, what was the nutritional composition of paleolithic mega fauna? Unfortunately, most these animals aren't around today but we can compare to modern analogues such as brown bears, polar bears, reindeer, and elephants.

Because archiological evidence indicates that paleolithic man favored hunting cave bear (they were completely decimated due to over-hunting) I tried to locate the fatty acid profile of modern bears. The largest bears that I could find the fatty acid composition for were polar bears, which should be appropriate given that the cave bear lived in northern latitudes. According to the study, Polar Bear (Ursus maritimus) Adipose Tissue Fatty Acid Composition Compared to Fatty Acid Constituents of a Common Milk Replacer, polar bears have on average 30 percent saturated fat, 50 percent monounsaturated fat and 15 percent polyunsaturated fat. These figures don't add up to 100 percent, but they are the figures as presented in the article. Bears are known to carry a significant amount of fat, especially towards the end of summer and into autumn. This seems adequate to maintain a ketogenic lifestyle for at least part of the year.

If you look at the fatty acid breakdown of the horse, a large grass-fed animal similar to what might have been available to paleolithic man, you find a large proportion of saturated fats. Horse fat is about 36 percent saturated fat, 34 percent monounsaturated fat, and the rest polyunsaturated fat. Even rabbits carry over 40 percent of their fat as saturated fat, but rabbits have much less fat per weight than the larger animals and as noted earlier, make a poor source of food when on a ketogenic diet. [source]

At any rate, I do think isotope studies are limited in the capacity that they cannot identify uncommonly consumed foods which might have had cultural or medicinal purposes, however in terms of deducing an average macro nutrient ratio they are more than sufficient when combined with archeological evidence. Specifically regarding your point about recent dietary adaptions, I agree that they are occurring as is evident by some people's ability to process lactose and gluten. However, if these two adaptations are supposed to be benchmarks for progress, than we still have much further to go before we have evolved to live successfully on a predominantly carbohydrate diet.

Edited by Skotkonung, 07 October 2009 - 01:00 AM.

[Skötkonung]

Not that it would be a definitive answer to this debate on ketosis and IGF-1, but I will investigate as to whether my insurance covers (or the exact cost if not covered) for IGF-1 testing. If it is not cost prohibitive, I will voluntarily do a non-CR ketogenic diet for two months and measure my IGF-1 at the beginning and end.

[Blue]

To quote from the isotope study you cited: ""Isotopic analysis provides information about the sources of dietary protein over a number of years, even though it does not measure the caloric contributions of different foods. As the method only measures protein intake, many low-protein foods that may have been important to the diet (i.e., high caloric foods like honey, underground storage organs, and essential mineral and vitamin rich plant foods) are simply invisible to this method.""

So no, you would not see a high intake of low-protein, high-carbohydrate or high-fat foods foods with this method. The study never clams to show that protein intake was exclusively animals. It states, regarding both Neanderthals and humans, "mainly animal sources", which, again, does not exclude a lot of low-protein foods.

Again, Neanderthals are not human. Many differences between are our species.

Did the Inuits have ketosis? That should settle if an almost exclusively animal and high-protein, high-fat diet can cause ketosis.

Edited by Blue, 08 October 2009 - 02:40 PM.

[JLL]

Returning to the issue of IGF-1 in omnivores and vegetarian diets...

Are diet–prostate cancer associations mediated by the IGF axis? A cross-sectional analysis of diet, IGF-1 and IGFBP-3 in healthy middle-aged men

We examined the association of diet with insulin-like growth factors (IGF) in 344 disease-free men. Raised levels of IGF-1 and/or its molar ratio with IGFBP-3 were associated with higher intakes of milk, dairy products, calcium, carbohydrate and polyunsaturated fat; lower levels with high vegetable consumption, particularly tomatoes. These patterns support the possibility that IGFs may mediate some diet–cancer associations.

Insulin-Like Growth Factor I, Insulin-Like Growth Factor I Binding Protein 1, Insulin, Glucose, and Leptin Serum Levels Are Not Influenced by a Reduced-Fat, High-Fiber Diet Intervention

full text here: http://cebp.aacrjour.../15/6/1238.full

Edited by JLL, 10 October 2009 - 02:01 PM.

[lynx]

Take a look at Aubrey deGrey or any other vegetarian, they look like a walking viral infection. All one has to do is look at human teeth to figure out what our diet should be composed of. Vegetarianism is more of an "ism" than a health strategy.