- I've been a lazy motherfucker about blogging recently, arousing the ire of a bunch of you, but fuck it- I work for free, which means I work whenever the fuck I feel like it, haha.
I know that some of you are still highly skeptical of my initial premise- that people of different racial/ethnic phenotypes are biologically varied enough to justify markedly different diets. First, consider this- natural selection, as an educated person knows, is a phenomenon in nature in which the mean phenotype of a given species moves a fraction of the way towards the local optimum phenotype, while gene flow causes the mean phenotypes to be averaged. Thus, ethnic pheotypes develop first according to environment, and then are gradually modified by gene flow over time. (TPG 118-128) You might think, upon first reflection, that this would merely mean that a person's ethnic diet would rely solely on the area from which his ancestors came and the available flora and fauna therein, but think for a second about what else would occur- the area in which those people lived would also exert a profound effect upon that ethnicities' biological makeup as well. Thus, not only would they develop a prounounced increase in metabolic abolity to digest lean meats if they lived in a rocky, mountainous area like the Caucasus, where goats might be a prevalent source of calories, but the people living there and hunting those goats would develop greater lung capacity and ability to metabolize oxygen, due to the altitude in which they lived. Their physiques would then change over time, both ontogenetically and genetically, to facilitate success in these regions.
It is this way, through both a tradition of very specific diet and exercise, that certain ethnicities developed a genetic predisposition to certain types of exercise- the Kalenjin of Kenya became the world's most dominant runners due to a long and storied tradition of running great distances at high altitudes, the Norse (described throughout ancient texts about the Germanic tribes as 'immense' and 'strong') developed world-famous size and strength, allowing them to dominate modern strength competitions, etc. (PP 171-172, 181)
As you can imagine, these taditional diets and lifestyles would continually reinforce themselves, creating a distinct biological phenotype for that ethnicity. It's not just the placement of their organs or the levels of efficiency displayed therein that would change, though, or simply their skeletal structure. The composition of their muscle fibers, in addition to a genetic predisposition toward an ideal muscular bodyweight, would also emerge, which would then create in that phenotype a distinct biological nutrtitive need.
Stay with me, baby birds.
Examples of titties, type 2, and type 1 fibers, respectively.
The human body is comprised of two major types of muscle fibers- type 1 and type 2. Type 1 muscle fibers are called slow twitch fibers, which are slow to contract, have an abundance of mitochondria and are surrounded by capillaries to bring in nutrients and carry away waste- these are the fibers that facilitate success in endurance sports. Type 2, obviously, would be the type associate with strength, contracting and relaxing faster, having higher glycolytic activity (that means greater use of muscle glycogen, and greater stores thereof, for the slow ones), greater phosphagen stores, and less capillaries.(NT 151) All muscle fibers can respond to athletic training by improving their ability to perform according to the way they're trained. Training aerobically, like the Kalenjin, increases the mitochondria and capillaries in type 2 muscle fibers, while training anaerobically enhances the phosphagen system of the type 1 fibers. Thus, even though most people have a muscular composition of about 50/50 type 1 and 2 fibers, training aerobically or anaerobically can make the fibers unsuited to a certain type of training more akin to those that are. This is what makes those crazy-ass log running Xavante indians in Brazil good at running long distances carrying 200 lb logs. Westerners, however, suck shit at that sport.
Thus, the demands their physiques would place on a phenotype's respective metabolisms would be altered even further. It is this combination- dietary availability, traditional recreational activities, traditional work activities, and basic evironment- that creates the basis on which metabolic types have arisen. It's because we no longer stick to our traditional stomping grounds, due to displacement and migration owing to the general shittiness of modern life, that have left us utterly confused as to how to eat. Well, that and ridiculous subsidies by the asshole peddlers of shit we shouldn't eat, like corn, the makers of Twinkies, and all of the other evil motherfuckers that comprise multinational corporations worldwide.
Next up, the history of metabolic typing, so help me Odin.
Felsenstien, Joseph. "Contrasts for a Within-Species Comparative Method." Modern Developments in Theoretical Population Genetics. Slatkin, Montgomery, and Michael Veville, Eds. Oxford: Oxford University Press, 2002.
Ivy, John, and Robert Portman. Nutrient Timing. Laguna beach: Basic Health Publications, 2004.