"I will try to express myself in some mode of life or art as freely as I can and as wholly as I can, using for my defense the only arms I allow myself to use -- silence, exile, and cunning." -- James Joyce
While it is true that many paleos on the internet do repeat that "10,000 years ..." line, it certainly isn't central to the point that not all people are fully adapted to certain foods. Extending the period to 30,000 years doesn't change this.The contention of the actual professionals within the paleo-sphere is that there are certainly some people whose genetics are such that they can tolerate certain foods, which is fine, but that not all people have become fully adapted (obviously, there is variation). Whether or not those who are tolerant of certain foods actually thrive on them is a different matter, but clearly those who are not tolerant cannot thrive on these foods (thus it is best that they eschew them altogether). I ate the SAD for most of my life without any noticeable symptoms. However, after I removed gluten-containing foods from my diet for a few months and then reintroduced them, it became very clear that I am highly symptomatic for gluten intolerance (possibly celiac). In fact, things that I thought were totally unrelated (CTS, back pain, edema, hemorrhoids, etc) were entirely linked to my gluten consumption. Once I removed those foods containing gluten (and to a lesser extent casein), all of these ailments disappeared. Diet, like religion and politics, is one of those areas where people can become very fanatical. This often leads the proponents of a certain thing to declare that their way is the only way, and that there is no deviation from it. However, the way that I approach diet, and the way that guys like Mathieu Lalonde and Robb Wolf approach it, is that it is an n=1 experiment. In other words, there is no generally applicable diet that meets all people's needs-- there is far too much variation for that-- but we can identify a basic blueprint as a starting point and then allow for individual experimentation (i.e. reintroducing certain foods and look for specific symptoms). The same applies to micro and macronutrient levels, both absolute and relative. For instance, I know that I thrive on a relatively low-carb diet, only adding in more carbs when I am more active. However, if I were to everyday eat the same amount of carbs that I do when I am very active, I generally just get fat regardless of caloric intake. Obviously, I cannot say that this would be the right approach for you or anybody else, because you just may thrive on a higher carb intake (see the Kitavan diet). Even though I was already generally "paleo" before I ever even heard of the "paleo diet", I still think that this variation method of dietetics is what attracted me to the people working within the paleo side of nutrition. They weren't saying, "this is the only way to eat", instead they were saying, "this is what we know about anthropology, genetics, epigenetics, nutrition and human physiology. Take these and apply them through self-experimentation to see what approach best works for your individual case". After having been immersed in the dietetics literature for many years, this approach to human diet was far more refreshing than the alternatives.
"that not all people are fully adapted to certain foods."Yeah, of course not! My wife's people never herded cattle or sheep, and never grew wheat: she has difficulty digesting those foods. I don't see what that has to do with the typical paleo diet screed that tries to tell me that an Irishman can't digest those things either!Joe, if you're version of a paleo diet is more sensible in this regard, recognize that that is not what we are attacking!
I understand, you're essentially attacking what I often refer to as the "paleo nazis". I'm totally with you on that, I often cringe at what these people say. It's funny, because that whole 10,000 years line was essentially an oversimplification used as a means of marketing the paleo diet, but most of those who continually repeat it are ignorant to this fact and take it as gospel. Really it's just the general period where many of the world's cultures moved from a hunter-gatherer society to an agricultural one. Obviously, this doesn't mean that certain cultures didn't adopt agriculture before or after, or that the foods that were grown weren't eaten before this period (they obviously were, just not as often). My background is equal parts German, Hungarian, Irish and Sicilian. One would think that with this entirely European background that I would be adapted to gluten (and casein), but when one considers that many (not all) European societies were actually pretty late in adopting agriculture, as well as adopting grains as a staple food, then it makes sense that I am intolerant of gluten. In fact, nearly 1/3 of Americans excrete immunoglobulin A in their feces when exposed to gluten-containing foods, and most of these people do not have the genetic markers for celiac disease. I don't know for sure, but my guess would be that most of these people have predominantly European backgrounds. But it's not so easy to say that people from certain regions will have certain traits, because there may have been much mixing of genetic material in that person's genealogy well before they found themselves in that region. For instance, I have a blood deficiency called G6PD. This is a hereditary disease that almost exclusively comes from Africa, the Middle East, and the Mediterranean. One would think that I would have gotten this deficiency from my Sicilian grandfather (this seems like the logical choice), but I actually got it from my Irish grandmother. Obviously, there is a lot more going on with my grandmother's genealogy than meets the eye, there was certainly some mixing of genetic material from other areas before her family found itself in Ireland, even though she has all of the classic Irish features. Interestingly, the Irish have a higher incidence of genetic markers for celiac than most other ethnicities, so it is quite possible that my gluten intolerance also came from her. As I hope that you've gathered, I am quite different than most people who discuss diet (or other subjects) on the internet in that 1) I aim to be intellectually honest, 2) I question every statement, and 3) I actually study the relevant disciplines. Most people just repeat the dogma told to them, which just reveals their ignorance and has a poor reflection on those of us who aim to find the truth. You find this in just about every subject, paleo (diet) is certainly not an exception in this regard.
Absolutely, Joe. The basic idea that our ancestor's evolutionary past can effect what we can and can't digest properly today is absolutely sound. And this was too often neglected in the past. The fact that many southeast Asians are now realizing they aren't adapted to eating dairy or wheat, e.g., is a wonderful thing. So I don't think our takes on this are very different at all.
"... this was too often neglected in the past"That's very true, but you must also consider that most of the relevant disciplines are still very young at this stage. Dietetics, genetics, epigenetics, anthropology, etc, are all extremely new sciences in the relative sense. Even today, many of those within the dietetics profession entirely ignore these other important related disciplines (to their detriment), instead favoring observational food studies for their research. There's nothing wrong with observation, but too often I find that there is much bias and shoddy science being done in these studies: one of the more popular studies showing a correlation between the consumption of animal foods and mortality uses as its test food an Egg McMuffin (!). The controlling of factors is also a great problem, I have yet to have seen a controlled study of any importance in the field of dietetics. Then there is the internet. No doubt, I am a firm supporter of the freedom of information, but I also know that I must keep my bullshit detector on the max setting when surfing the web. Too often, with the full freedom of information, the message meant by a professional within a certain discipline will be taken up by the masses and changed to their desired meaning. A good example of this popped up in both the low-carb and paleo web communities, I'll explain:It's a well-established and scientific fact that the human metabolism does not require the ingestion of carbohydrate energy to sustain life (i.e. carbohydrates are not an essential nutrient). This is not to say that glucose is not required for energy or cell synthesis, the body obviously does need glucose for certain metabolic functions, but the human body has adapted to make its own glucose through gluconeogenesis and the splitting of triglyceride bonds. Pretty cut and dry, and it certainly makes sense when you consider that most of these carbohydrate foods would not have been available year round during our evolution.Unfortunately, the internet paleo-sphere, instead of concluding that there are some benefits to ingesting carbohydrate energy (indeed there are), decided that all carbs are bad. Though shalt not eat carbs, they said, because they are not necessary to life. The problem that arose from this is that while all of the professionals who are proponents of the paleo diet were insisting that your carb intake is based upon many factors (individual physiology, metabolic status, activity levels, etc), this was all entirely ignored and paleo then came to be known as a VLC (very low-carb) ketogenic diet, which is anything but. Robb Wolf attempted to address this in a 3-part series of blog posts on the subject. He essentially concluded that while carbohydrates are not essential for life, they do have certain benefits, especially for those of a certain physiology or lifestyle. He basically said that while ketosis can be a beneficial tool to use in certain circumstances, it certainly is not the natural state for most humans, and it certainly is not beneficial for those who are intensely active (i.e. athletes). He was completely blasted for this and was called many names. People even said that he was "selling out", but to whom I still have not yet identified. It was a situation that revealed rife fanaticism within that small sector of nutritional science. Anyhow, I think this whole thing with the 10,000 years is very similar. The paleo-sphere, instead of concluding what they had been told-- that not all (possibly most) people have entirely adapted to certain grains-- instead concluded that NOBODY has adapted. This simply is not what the pros were saying.