The Dude Abides said...
What's your position on saturated fat? That is, do you feel that its consumption is completely benign? Or, do you believe there should be some limits on the amount consumed?
Hi Dude!
I, like most people, used to think saturated fat was bad for us - but now it’s become clear that we have all been misled about
the science on this since the 1950's
the story is a complex one, and one that is at odds with many of the assumptions most of us have absorbed as we have grown up.
but - It’s well documented now that the obsession in the west with fat as a cause of cardiovascular disease was based on the Hypothesis of one guy in the 50's trying to make a name for himself - Ancel Keys.
He presented observational data on dietary intake and cardiovascular disease which he claimed proved a causative link between saturated fat intake and CVD
Around this time government in the USA was starting to be alarmed by rising rates of CVD in the general population - and Keys, an astute political influencer, rose to prominence as a key figure in dietary science.
Today its considered poor science to draw any firm causative links from observational studies - even if they are well done and above board. It’s now accepted that these studies can only demonstrate association and not causality, and that there are always confounding factors that cannot be fully accounted for.
And, on top of this, it turns out, Keys manipulated the data set in his observational study of 7 countries to fit better with his preferred hypothesis.
eg he excluded France - which is known to have a high fat intake and low CVD
and failed to account for various other confounding factors, which are always present in observational studies. including one large and well-known factor - sugar consumption.
However, at the same time as this theory was gaining momentum with policy makers - mass media was exploding in the western world and with it modern marketing techniques.
Big food producers were keen to cash in on this new "science". So many foods that didn't have any fat in them to speak of were now marketed as "Low Fat" an "Heart Healthy" - and over the next decades cereal packets on every breakfast table in the west repeated the same slogan and the dietary fat hypothesis became pretty much an accepted fact.
later - based on this hypothesis and the market opportunity created by the low fat marketing - low fat dietary products and fat replacement products later flooded the market - but sadly, despite the cornucopia of drugs and surgical interventions designed to keep people alive for monger - this did little to slow the rise of CVD in the West
there were also glaring inconsistencies visible in the outside world for anyone who cared to look
for example
-the Inuit have a diet heavily reliant on animal fat - mainly seal blubber - which they literally ladle onto almost every meal - and yet CVD is almost unheard of in their native population
-tribes in Africa live almost exclusively off their cattle herds - eating mainly fat and protein and again CVD rates are exceedingly low
- same for reindeer herders in northern Russia
- native Americans lived of the herds of bison on the great plains etc
And yet when all of these population convert from their traditional diets to western foods – they tend to suffer all the same chronic diseases we do.
Despite this no one seemed to question to received wisdom - and it seems the government were reluctant to back track even when more evidence casting doubt on earlier theories came to light.
the upshot is in my opinion all indicative of a distorted paradigm with which to view food.
ie a reductionist approach - that assumes food is a mixture of individual chemicals that can be broken down into - ie the same basic macro and micronutrients - such that regardless of source - if we consume these nutrients they have consistent effects on our biology
this patently false
-a fat is not a fat
-a carb is not a carb
the mixture is more than its constituent parts - its structure defines how it interacts with our bodies just as much as its constituent parts - so it becomes inherently unreliable to consider food through this lens
in addition, fats are a complex mix of compounds that may be
-saturated or monosaturated or polyunsaturated
-they may be short medium or long chain molecules
-they may be Omega 3 Omega 3 or Omega 9 forms
-processed fats may be hydrogenated or partially hydrogenated to alter their melting points or texture -or they may be trans fats
-Fats (especially polyunsaturated fats) can also be oxidised or damaged –
Proteins are similar
Carbohydrates too
And all food is simply not equal to its constituent parts in the sense that the reductionist approach implies
So, in general, i believe we have evolved to eat naturally available foodstuffs that we hunted and gathered as we expanded around the globe in the 250,000 years that Homo Sapiens have existed.
very little genetic adaptation beyond this has been found in the last 10,000 years – ie the time in which we have been doing any form of farming – and that demarcates the point at which diets high in anything other than animal fat and animal protein became possible. In fact, the practice of farming crops actually took until around 3,500 years ago to reach our ancestors in Western Europe from Turkey where it began. This is only a matter of 150 generations or so – a very short time in terms of evolution and natural selection.
Before this, there were no crops and we were largely hunting game - mostly ruminants and gathering nuts seeds and roots to supplement that largely animal based diet.
Our most dramatic changes in diet, sugar intake, processed food, artificial additives have taken place over only the last 2 or 3 generations- ie no-where near enough time to adapt in evolutionary terms
So, i believe what we see in modern civilisation as an epidemic of chronic inflammatory disease processes such as CVD, Stroke, auto-immune disease, Alzheimer’s - some cancer - are all largely driven by the inevitable chronic inflammation caused in response to deviating from the evolutionary template we evolved with in symbiosis with our environment.
everything we do in modern life that does not fit with that template, be it trans fats, excessive carbohydrates, air pollution, social isolation, pesticide residues, lack of exercise, lack of sleep - all drive inflammatory responses in the body – which, over time, lead to disease
so, in the context of an evolutionary compatible lifestyle - i don't think high consumption of saturated fat from healthy sources causes health issues - even if the quantities are such that it’s the majority of the calorific intake.
but, the consumption of high quantities of factory or feedlot raised meat, which contains a different fat profile to wild or traditionally raised meat, or seed oils, in combination with a traditional western diet high in processed carbohydrates, trans fats, pesticide residues, artificial additives etc may well do.
This is at least how I now think about
it
Sorry for the essay – i struggled to unpack what seemed like a simple question without going back and providing context and the historical setting