The Paleo Diet – Brilliantly Simple, or Simply Wrong?

Introduction to the Paleo

 According to thepaleodiet.com, “the Paleo Diet, the world’s healthiest diet, is based upon the fundamental concept that the optimal diet is the one to which we are genetically adapted.” Who can disagree with that? After all, it does make sense that the best diet would be one that, according to our genetics, our body can utilize most efficiently. However, is this what the Paleo Diet actually offers?

The Paleo Diet claims to offer “modern foods that mimic the food groups of our pre-agricultural, hunter-gatherer ancestors.” First we have to look at what the Paleo Diet means by our “ancestors.” Being a “paleo” diet, it is referring to our ancestors in the Paleolithic era, which extends from about 2.5 million years ago to about 10,000 years ago, just after the end of the last ice age and around the dawn of the Neolithic – or agricultural – revolution. 2.5 million years is a pretty broad range to select a diet from, but perhaps not so broad on an evolutionary timescale.

One issue that arises when studying the diets of ancient hominids is the fact that archaeological sites aren’t all too common past 10,000 years ago. The reason probably lies in the fact that prior to the Neolithic revolution, people were hunter-gatherers. They didn’t really have permanent settlements. Hunter-gatherers travel to where the food – presumably that which can be hunted (migratory animals such as elk, bison, caribou, etc. depending upon geographic location) and gathered (berries, nuts, shellfish, and so on) – is. This would vary by the season and even by the century as animals permanently migrated to new locations or became over-hunted in their current location. However, when mankind developed agriculture about 10,000 years ago, people began to establish permanent settlements. These settlements, which were fueled by the domestication of plants and animals and thus liberation from hunting and gathering, provide a rich source for archaeological artifacts. It’s difficult to find the few material bits and pieces of a nomadic lifestyle. When people settle for hundreds or even thousands of years in a location, artifacts build up, and the chances of finding something 10 millennia later are much greater.

How do we know about their diet? Archaeological evidence

So, how do we know what the hunter-gatherers ate? One way is to look through the archaeological sites that we do have. Animal bones are often signs that the inhabitants ate meat. Furthermore, we might find tools that could have been used for butchering along with cut marks on the bones that imply that the animal was butchered. Along with this, we can track morphological changes over time. Changes in the size and structure of certain bones, such as the mandible and cranium, might indicate a change in diet. A diet heavier in meat could require a larger mandible and would imply an increase in calories that would be necessary to support a larger brain in the larger cranium.

Osteological analysis, though, is qualitative at best. It’s important to remember that an archaeological site is merely a snapshot in time. For example, a site that was abandoned in the winter (maybe to move somewhere warmer, a death of the inhabitants, or something completely different) might show a heavy use of meat due to the fact that not many plants grow in the colder months. With so few sites, there isn’t very strong evidence one way or the other about diets. Small sample sizes can be incredibly biased.

Stable Isotopes

Another way is to study ancient diets is by using stable isotope analysis. If you remember from chemistry class, isotopes are two elements with the same number of protons but a differing number of neutrons. Because proton (atomic) number defines elemental properties, the two elements are actually the same element, but with slightly different weights. For example, about 99% of the carbon in the atmosphere is C12 – carbon with an atomic mass number (combined number of protons and neutrons) of 12. This is the most stable form of carbon, and thus the most abundant. Carbon has two other isotopes that are relevant to scientific studies, C13 and C14. Though there are many more isotopes, they are found in minute amounts and are so unstable that they decay rather quickly.

You have probably heard of carbon dating, which measures the relative abundance of C14 in an organic artifact and derives an approximate date based on known rates of decay for C14. This works based on the fact that there is a certain ratio of C12 to C14 in the atmosphere, which is taken up by organisms. After the organism dies, C14 begins to decay due to its heavier weight. While this is based on the assumption that C14 to C12 ratios were the same in the past, it can often be cross-verified with other forms of dating, such as stratification, phylogenetic dating, other forms of radiometric dating, and sometimes even early writings (for example, the date derived from carbon dating an item purportedly from some event can be compared to a written, dated historical document describing the event).

Stable isotope analysis works, as the name implies, by measuring a stable, rather than radioactive isotope. Because C13 is not heavy enough to decay (C12 and C13 are the only stable isotopes of carbon, and C14 is the most stable radioactive isotope), it will remain in the bones and teeth in the same C12:C13 ratio as when the organism was alive. Great! Although C12 and C13 are not discriminated in our bodies, some plants distinguish between C12 and C13, ever so slightly. Ribulose-1,5-biphosphate carboxylase/oxygenase – commonly known as RuBisCO – is an enzyme that, in most plants, binds to the CO2 entering the stoma. Rubisco happens to have a slight affinity for C12, meaning the plant – and everything that eats the plant – has a disproportionate amount of C12 to C13. These plants are known as “C3” pathway plants.

In arid climates, where water is even most precious, plants had to adapt. A problem arose due to the fact that water escapes from the stoma when it opens to have rubisco capture CO2. Therefore, some plants, known as C4 pathway plants, evolved to use another enzyme, PEP-carboxylase, to bind CO2. PEP-carboxylase binds much more strongly to CO2 than rubisco, and doesn’t present a preference for either C12 or C13.

Carbon isotopes are used in conjunction with other elemental isotopes, such as nitrogen, to assess relative ratios of plant to meat in diets. This is all based on small differences between heterotrophs and autotrophs, carnivores, herbivores, and omnivores. For example, organisms higher in the food chain tend to have more N15 than organisms lower in the food chain. It is important to understand the isotopic variation of the ecosystem, however, they can vary, especially when environmental manipulation (such as cooking) comes into play. Ultimately, stable isotope analysis has a modest amount of discriminatory power, but is not comprehensive. It utilizes quantitation to make a qualitative claim, and does so on a limited number of samples.

Problems with the logic of a Paleo Diet

Which “paleo” should we eat like? 10,000 B.C.E. Inuit people? 200,000 year old Mitochondrial Eve? 1 million year old Homo erectus? Clearly there were times, and species, of hominids that ate more meat than others. An Inuit living in north Canada survived largely off of seal fat. However, Homo erectus probably lived more off of fruits and nuts. Humans survived and came to dominate the planet due largely to their adaptability, including our omnivorous diet. Our ability to adapt to mostly nuts or mostly blubber has granted us freedom to roam from the heart of Africa to the frozen lakes of Canada. Paleolithic hunter-gatherers simply ate what was available to them.

Many Paleo dieters cite articles discussing health disparities that arose when agriculture entered the picture. While this is true, it’s not necessarily because we stopped eating a “paleo diet.” More likely, health problems arose because we stopped eating such a wide variety of foods. Many ancient peoples went from elk, bison, nuts, and berries to what we could domesticate. Eventually, our domesticated crops and animals grew in variety and things leveled out a little more. This was likely not a rapid transition. Domestication may have started out as simply a way to supplement hunting and gathering before the boom of the Neolithic Revolution. Regardless of your diet, it is important to eat a variety of food in order to encompass all nutritional ingredients. Many people in Westernized cultures today eat a much more monotonous diet than they should.

Are we genetically identical to our “Paleo” brothers and sisters?

One of the main arguments of the Paleo Diet is that our genome has changed little since the end of the Paleolithic period, meaning our bodies are still best adapted to the diet of that time. This argument is a bit short-sighted. To claim that our genome has not adapted to our Neolithic lifestyle is simply incorrect. It is true that our genome evolution lags far behind our cultural evolution, and is often overshadowed by it. However, there do exist some key differences in our genomes from those of a Paleolithic hominid. The two most well known adaptations are the amylase and lactase mutations. Amylase is an enzyme that allows for digestion of starch from grain. As the Neolithic Revolution kicked into gear, those with an extra copy of the amylase gene better metabolized all of the new grain they could grow. This extra gene places amylase in the saliva, helping break down the starch at the beginning of digestion rather than beginning halfway through in the gut.

The second mutation is a regulatory mutation. People are born with a gene that regulates the production of lactase, an enzyme that breaks down the biologically unusable dairy sugar lactose into the biologically usable sugars galactose and glucose. Before animal husbandry practices of the Neolithic Revolution, the lactase gene would be transcriptionally inactive, or “turned off” in most people around the age of 5-7. After this age, the child no longer breast fed, and really had no need for lactase. However, once people began raising dairy animals, such as goats and cattle, dairy products such as milk and yogurt became an important staple food. This seems to have caused positive selection for the genetic mutation that allowed the lactase gene to remain “on” throughout life. Those with the lactase and amylase mutations could better exploit dairy and grain products than those without the mutations. So, while our genomes are not radically different, they are indeed different, and have adapted to some of the Neolithic diet changes.

Microbiomes

Although our genome is relatively similar to our ancestors, our microbiome certainly isn’t. The microbiome is the summation of microorganisms that inhabit us. This might not seem like a big deal, so let me put it in perspective. If we were to take the entire amount of DNA in your body, including that of the microorganisms, human DNA would comprise only about 10%. The other 90%? That would be the microbiome. You are 90% microorganism. With the recent completion of the human microbiome project, expect to see some incredible discoveries about the differences between ourselves and our Paleo ancestors in the near future.

So how do we study the Paleo microbiome? One way is through ancient DNA. Unfortunately (or fortunately, for researchers today), there were no Paleo dentists around, nor were there any Paleo toothbrushes. When people ate, plaque built up and calcified on their teeth. This calcified plaque is called dental calculus, and it preserves the DNA of the microorganisms that made up the plaque along with some of the DNA from the actual food. From this, using Next Generation Sequencing techniques, we can learn more about the kinds of food and the microorganisms that were present in the bodies of our ancestors. By comparing what we find to oral microbiomes today, we can have a better understanding of what Paleo people ate. Also, microfossils can be preserved in the dental calculus, allowing for a visual confirmation of food in the plaque. Again, these are qualitative measures that are inhibited by sample size. But, these are the best methods we have and they are producing some excellent research.

Is the food still the same?

People freak out about GMOs. The truth is basically everything we eat – meats and plants alike – are genetically modified. Over thousands of years we have artificially selected plants and animals for particular traits. As our genome has changed since Paleolithic times, plant and animal genomes have radically changed, largely due to human manipulation. So, even if you eat according to the Paleo Diet, you are eating the modern-Paleo Diet, not the Paleo-Paleo Diet. So, really, you aren’t even eating like you think the ancestors ate. Our modern plants are “human inventions,” as Dr. Christina Warinner – a leading Dental calculus expert at the University of Oklahoma – puts it.

Ultimately, the Paleo Diet, as it is marketed, isn’t really a Paleo Diet at all. There’s no harm, and definitely some benefit, in cutting refined sugars and overly processed meats out of your diet. However, eating modern versions of nuts, fruits, veggies, and more meat isn’t going to make you any more like a Paleo-man or Paleo-woman than if you just eat a normal, balanced diet. If anything, skipping out on legumes, dairy, and multi-grain wheat, which are prohibited in the Paleo Diet, could cause a lapse of certain nutrients. Technological and agricultural advances have produced some amazing foods that our Paleo ancestors could have only dreamt about. If you really want to be Paleo, then take advantage of the advances in food science. It’s what our ancestors would have done.

*A form of this is also published at http://anthronow.com/wp-content/uploads/2016/04/AnthroZine_1601.pdf

 

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Biocentrism – An Alternative “Theory of Everything.”

For a long time, physicists have dreamt of a unifying “Theory of Everything” that would amalgamate every physical aspect of the universe into one packaged theorem. As of now, physics hangs in the balance between Einstein’s Theory of General Relativity (GR), which does a pretty great job of explaining relationships between macrocosmic entities, and Quantum Field Theory (QFT), which does an excellent job of showing that GR is wrong on the microcosmic scale, but we aren’t sure why. Both have tremendous explanatory power (though nobody really knows what QFT is actually saying), but, unfortunately, are incompatible cosmologies. Subatomic particles, explained by QFT, simply don’t fit the laws of GR. God may not “play with dice,” as Einstein put it, but apparently he does roll subatomic dice. Truly, QFT embodies Aristotle’s maxim, “the more you know, the more you know you don’t know.” More recently, physics has also devised String Theory, of which various versions can be incorporated into a multi-dimensioned theory known as “M-Theory.” M-Theory also has incredible explanatory power, accounting for all of the fundamental forces and types of matter. It’s a great hypothetical framework, but lacks a practical aspect that is necessary in any strong scientific theory, making it about as believable as any other cosmological mythology. While these “Big 3” theories are all contained within the realm of physics, Robert Lanza claims there is a 4th, more appropriate explanation. And it lies within the realm of biology.

Robert Lanza is a leading stem cell researcher and Chief Scientific Officer at Advanced Cell Technology. He is one of the world’s most respected biologists, having been mentored by giants in a variety of scientific disciplines, including Jonas Salk (developed the first Polio vaccine), B.F. Skinner (famous psychologist and behaviorist), and Christiaan Barnard (performed the 1st heart transplant). In other words, Lanza has a lot to lose, and likely wouldn’t tarnish his reputation on something he didn’t deem worthwhile.

In his book, “Biocentrism,” Lanza offers a cosmology situated within the field of biology, specifically within consciousness. Regarding Biocentrism, Lanza notes 7 principles. I will list them all and then take a closer look at each one:

  • What we perceive as reality is a process that involves our consciousness. An “external” reality, if it existed, would – by definition – have to exist in space. But this is meaningless because space and time are also not absolute realities but rather tools of the human and animal mind.
  • Our external and internal perceptions are inextricably intertwined. They are different sides of the same coin and cannot be divorced from one another.
  • The behavior of subatomic particles – indeed all particles and objects – is inextricably linked to the presence of an observer. Without the presence of a conscious observer, they at best exist in an undetermined state of probability waves.
  • Without consciousness, “matter” dwells in an undetermined state of probability. Any universe that could have preceded consciousness only existed in a probability state.
  • The structure of the universe is explainable only through biocentrism. The universe is fine-tuned for life, which makes perfect sense as life creates the universe, not the other way around. The “universe” is simply the complete spatio-temporal logic of the self.
  • Time does not have any real existence outside of the animal-sense perception. It is the process by which we perceive changes in the universe.
  • Space, like time, is not an object or a thing, Space is another form of our animal understanding and does not have an independent reality. We carry space and time around with us like turtles with shells. Thus, there is no absolute self-existing matrix in which physical events occur independent of life.

That’s a lot to sort out. Let’s start with the first principle:

  • What we perceive as reality is a process that involves our consciousness. An “external” reality, if it existed, would – by definition – have to exist in space. But this is meaningless because space and time are also not absolute realities but rather tools of the human and animal mind.

The second half of this tenet is incorporated into the 6th and 7th, so I will just take a look at the first half. Yes, what we perceive as reality is a process that involves out consciousness, regardless of the sense that is used to perceive. And, yes, an external reality would need to exist in some sort of space, as it is external from our own perceptive machine, i.e., the brain. Our senses indeed mean nothing without consciousness. Similarly, you can perceive things that are not there, or misperceive a sound for, say, a color. For more information on this, look up synesthesia.

Now for the second:

  • Our external and internal perceptions are inextricably intertwined. They are different sides of the same coin and cannot be divorced from one another.

Again, I don’t see a problem with this statement. What you “see,” “touch,” “smell,” “taste,” or “hear” are all meaningless without interpretation from the brain, or consciousness. If I think about the number 4, the conscious process is not so different from when I see the number 4 and my brain interprets the meaning of the symbol.

So far so good, what about 3?

  • The behavior of subatomic particles – indeed all particles and objects – is inextricably linked to the presence of an observer. Without the presence of a conscious observer, they at best exist in an undetermined state of probability waves.

This one assumes that the physical instantiation of the whole is a sum of its parts. On a basic level, this makes as much sense as anything else. If the subatomic particles exist as waves when unobserved (see the “double slit experiment” for details), then so should the things that they compose. There can be some points of contention for this generality. For example, sodium (Na) and Chlorine (Cl) are both pretty dangerous to humans in elemental form. However, when they come together, they create sodium chloride, or table salt, the main ingredient in those delicious french fries. Perhaps subatomic particles have some yet undetermined attribute that causes their fundamental composition to change when combined together. This, however, seems unlikely. Then again, it’s quantum mechanics. Everything in quantum mechanics seems unlikely. Ultimately, this principle passes on the grounds of simple logic, but could be troublesome due to misunderstood properties of subatomic particles.

The fourth is linked to the 3rd:

  • Without consciousness, “matter” dwells in an undetermined state of probability. Any universe that could have preceded consciousness only existed in a probability state.

This principle follows logically from the third. Namely, matter, composed of subatomic particles, seems to exist as a wave until observed (i.e., perceived consciously). Thus, a pre-conscious universe would exist as a wave, suggesting it exists only as a probability.

The 5th is perhaps the shakiest principle:

  • The structure of the universe is explainable only through biocentrism. The universe is fine-tuned for life, which makes perfect sense as life creates the universe, not the other way around. The “universe” is simply the complete spatio-temporal logic of the self.

Lanza is jumping the gun a little here. Yes, it is possible that life (or consciousness) “creates” the universe, as the the subatomic particles that compose it might exist only as a wave in the absence of consciousness (or a conscious observer). As such, how we make sense of the things we perceive using space and time – the spatio-temporal logic of the self – is essentially the “universe.” The claim is bold, but not completely out in left field.

The 6th explains part of the 5th:

  • Time does not have any real existence outside of the animal-sense perception. It is the process by which we perceive changes in the universe.

For those unacquainted with physics or neuroscience, this seems radical. In fact, it even seems a little radical for those that are in the fields. However, it seems to be true. Time is a tool. Our brains are wired for connecting the dots. In order to connect the dots, we need a connector. This connector is time. Think of time as not so different from measuring length, weight, or any other attribute. If you can’t imagine how time might not exist, try imagining a world in which we cannot measure length. Yes, length exists, but need a ruler to compare them. As for events, they exist, and we use time to compare them. If this still does not make sense, do some independent research on the topic. It’s difficult to explain, and I’m certainly not the most qualified individual to do the explaining. However, it doesn’t defy anything really, so this one can be accepted as well.

And now to wrap things up with the 7th principle:

  • Space, like time, is not an object or a thing, Space is another form of our animal understanding and does not have an independent reality. We carry space and time around with us like turtles with shells. Thus, there is no absolute self-existing matrix in which physical events occur independent of life.

Again, space is how we compare our perceptions. It’s another “measuring stick” for what we perceive, much like time. In fact, quantumly entangled particles seem to defy space and time. They react instantaneously – faster than the speed of light. The faster you move, the smaller space becomes and the less time affects you. So space and time can both be changed depending upon the circumstance. This, taken with the fact that our consciousness is what interprets, and thus “creates” the universe, are Lanza’s main points for a non-existent physical universe. Again, this is difficult to comprehend, and I’m sure I muddy the picture more so than others. But, look into it and you might understand it more clearly.

So, those are the 7 principles of Biocentrism. On the surface, they seem to make sense. At least, as much sense as a physically oriented view of the universe. They’re just incredibly strange and require a complete paradigmatic shift in order to comprehend. The biggest thing that stuck out to me while reading Lanza’s book and claims of Biocentrism was the inception of the universe. According to Lanza, and perhaps other proponents of the Participatory Anthropic Principle (PAP), the universe existed in an indeterminate state before consciousness. Once consciousness arrived, the universe could be observed and thus materialize. However, wouldn’t the consciousness, embodied by a conscious being, only be a probability unless observed? It seems paradoxical.

Now, I don’t necessarily ascribe to biocentrism. I do think it explains a lot in a very interesting fashion, but it lacks the same practical testability and thus falsifiability that M-Theory lacks. Perhaps, as we begin to further understand QFT (or understand it at all) we will be able to better manipulate and experiment upon subatomic particles, thus providing evidence either for or against M-Theory and Biocentrism. Until then, these two cosmologies are too theoretical to act as a standing “Theory of Everything.” At any rate, I would definitely recommend the book. It’s an excellent, thought-provoking read that will challenge the way you see the world. You have to approach it with an open mind. A background in science wouldn’t hurt, but Lanza does a pretty good job of explaining concepts. I’ll end with a quote, again from Aristotle:

“It is the mark of an educated mind to be able to entertain a thought without accepting it.”

Keep that in mind if you read the book.