Wednesday, 17 October 2012

I don't like fatties, part deux...

Firstly - for those who may have been a little confused by my last post:  
NO - I am NOT a FASCist.  I am a FATist.  

fas-cist (fash-ist)
  1. a person who believes in or sympathizes with fascism
  2. a member of a fascist movement or party
  3. a person who is dictatorial or has extreme right-wing views

fat-ist (fat-ist)
  1. a person who holds  discriminatory views on overweight people 

Right then, now that that is out of the way...

In part one, I admitted by impatience with fat people.  I also admitted that, despite my superior brain to these obviously lazy folk, even I have had no luck in helping to lose weight, get healthy - and stay that way.  

And perhaps this fact led to my growing feelings of empathy for these unfortunate folk and my decision to look at things from another view... 

...and I came across quite a few folks who were looking at things a little differently: basically blaming the ‘obesity epidemic’ on an addiction to sugar. 

And it’s not like this is a new thing.  Fairly new to me maybe, but apparently folks identified food addiction at least as long ago as 1947, when Theron Randolph described it as  a “specific adaptation to one or more regularly consumed foods to which a person is highly sensitive - producing a common pattern of symptoms descriptively similar to those of other addictive contrast to the ordinary conception of food sensitization, the food addict is 'picked up' temporarily after a meal containing his addictant, but is 'let down' subsequently by the delayed recurrence of withdrawal effects or hangover-like symptoms...the addiction cycle, or the time elapsing between meals and the onset of the hangover, depends on the individual's degree of sensitivity and the phase of adaptation to the specific excitant or excitants."  In 1963, British biochemist Robert Kemp, in a series of studies, went further, identifying carbohydrates as the specific macronutrient that is most addictive. 

American researchers Richard and Rachel Heller outlined this concept in their 1991 book The Carbohydrate Addict’s Diet. They have since expanded upon their work in a number of articles and further books. 

But why would carbohydrates be addictive?  Isn’t it a necessary macronutrient?  Why would a biological requirement be addictive?  To answer to these questions, we must understand a little about evolutionary medicine.

Evolutionary Medicine can be described as the “synergistic meeting of anthropology and medicine” that probably began officially with work by Dr. Boyd Eaton and Dr. Melvin Konner, who in 1985 wrote a paper called Paleolithic Nutrition: A consideration of its nature and current implications, exploring how evolutionary concepts could shed light on modern health problems.  It proposed that the selection pressures faced during the long evolution of primitive species to humans could tell us things about the diseases - particularly chronic degenerative diseases - that we face today.  

Criticism of the traditional medical model as mechanistic, materialistic, reductionistic, linear-causal, and deterministic led frustrated scientists to begin looking at medicine and human health from a new perspective, believing the structure and function of an organism cannot be understood until it is studied against its historical background. (Delbriick)

*from this perspective, the roots of evolutionary medicine (and my introduction to the construct) can be traced back to work by Russian geneticist, Theodosius Dobzhansky, who wrote a ground-breaking paper in 1973 titled  “Nothing in Biology Makes Sense Except in the Light of Evolution” which argued that without the binding thread of evolution, biology (and its related ‘biosciences’ such as anatomy, physiology and molecular biology) is just a collection of miscellaneous facts, with nothing to link them together.*

Evolutionary medicine proponents argue that the portion of the human genome that determines basic anatomy and physiology has remained relatively consistent over the past 10,000 years (Cavalli-Sforza et al. 1994; Cordain et al. 1998). Thus, most of the current human genome probably evolved in the physically active hunter–gatherer environment and remains unchanged to this day (Cordain et al. 1998). Anthropological study of hunter-gatherer cultures show that so-called ‘western diseases’ - the 35 major non-infectious, non-communicable diseases we currently take for granted - are extremely rare in these populations.  That recognition forced inquiry - aided by the sciences of genetics and molecular biology - into the differences in diet and activity between Western civilization and hunter/gatherers. 

Around the same time, evolutionary biologist George C. Williams and psychiatrist Randolph M. Nesse came together in 1991 to publish a paper titled The Dawn of Darwinian Medicine, a pioneering work that outlined methods for applying evolutionary biology to modern medicine. They described Darwinian Medicine as the enterprise of trying to find evolutionary explanations for vulnerabilities to disease.  Williams and Nesse expanded on their work, and wrote a ground-breaking book in 1995 called Why we get sick: the new science of Darwinian Medicine.

By now, I’m sure you have figured out that the current ‘paleo movement’ was spawned from these advances in medicine, and this new perspective. It is from the work of a number of the new ‘Paleo’ authors that sheds additional light on why eating copious amounts of sugar may not necessarily be a great idea....

The paleo authors’ basic argument is thus:  the best food for the human species would be the kind of food that was available throughout the majority of our evolution, rather than those that were introduced long after the construction of our physiology. 

Our primate ancestors have been consuming fruit, vegetables, nuts and insects for 50 million years or more. Meat was successively added, with a probable increase around 2 million years ago. Underground storage organs (roots, tubers, bulbs, corms) possibly become staple foods 1-2 million years ago (Lindeberg).

Quick aside on paleo: no one can say with absolute certainty what we have adapted to eat.  It is highly dependent on the era and area studied. When and where do we draw the lines?  i.e. is ‘paleo’ what we ate on the plains of Africa 50,000 years ago, or is it what the ice-dwellers ate 500,000 years ago? Or both? The bottom line is it matters less what our ancestors ate, than what selective forces were at play and how we adapted to them.  There is ample evidence, for instance, that - despite the insistence of many paleo authors to the contrary - that the last 40,000 years have seen the fastest evolutionary rates in history, and we are far more capable of generational adaptation than previously thought.  An example is our relatively recent adaptation to the digestion of lactose (milk sugar).  Historically, humans only produce lactase (the enzyme that is produced to break down lactose) for the first few years of life, as an evolutionary strategy to digest breast milk; however, it is clear now that much of the world’s population maintain this ability throughout their lives.  We also use ideas and technologies unique to our current population to adapt to our environment and to help shape our evolution; an example being how we use technology to make grains and legumes much healthier. Rather than wasting so much of their energy on demonizing a great many ‘neo-lithic non-foods’, paleo leaders would be better suited joining in the real fight: the one against the processed industrial food industry that churns out nutrition-less crap designed to be addictive with no consideration for human, animal, or environmental welfare (McEwen). 

That being said, I have greatly enjoyed reading many of the works of these authors, and would absolutely recommend the books of Cordain, Sisson, Wolff, Taubes, the Hartwigs, and Gedgaugus.  Sisson’s and Wolf’s websites are also quite excellent, and I especially enjoy listening to Wolf’s podcasts.  Despite seeming to be a ‘Crossfitter’, he’s undoubtedly a smart dude.  

My take-away: recognize our shared evolutionary history; be more skeptical of the foods I eat - especially those that are not a part of that history; and through a series of self-experiments,  pay very close attention to how my body reacts to the fuel it receives.

In part three, I’ll break down the science behind why we eat sugar, and why we go back for seconds...and thirds.  And then, we’ll learn how chimps and elephants can help us stay skinny.