Problems with the Paleo Diet May 5, 2016Author: Beach Combing | in : Prehistoric , trackback
We are digital human beings living in caveman’s body. This, at least, is the perspective of a growing number of nutritionists and their followers: who explain problems in human health through our eating Neolithic or, worse, industrial foods. The natural conclusion is that, for our bodies’ sakes, we can surf the internet and drive cars, but that we should return to the Stone Age when we eat. But does this argument really stand up to any kind of scrutiny?
First of all, let’s establish the ideal. Our nomadic ancestors’ – before the great escape from the seasons when we settled and grew things – lived lives that most anthropological and some archaeological evidence suggests was gendered. Men hunted and women gathered. What would a hunter-gatherer’s daily food ration actually look like in the tropic or temperate band of the earth? Archaeological remains favour the big cuts of steak: wild boar bones survive much more easily than, say, berries. But anthropologists looking at hunter-gatherer societies in the nineteenth and twentieth-centuries and today have corrected this bias. A gatherer perhaps brought in as many as sixty different objects to the family fire: an incredible variety of roots, fruit, grubs, fungi etc etc. Meat eating, on the other hand, seems to have been more about the Sunday roast: it was occasional (and unpredictable). In short, hunter gatherers were really gatherer-hunters: if you had to do without one or the other, you ditched the wild game.
After this things get messy. The ‘classic’ proportion of meat in the diet is one quarter: though probably there was no meaningful average. Certainly, modern hunter gatherers have eaten vastly different proportions of animal flesh depending on where they live: traditional Arctic peoples are practically carnivores, for example; some island hunter-gatherers, where stocks of meat were hunted out, became, meanwhile, largely vegetarian. Both populations thrived. Human beings are above all adaptable. There is also controversy about how much was cooked and how much was eaten raw. British anthropologist Richard Wrangham has argued from anthropological evidence (though the archaeological evidence is incomplete) that human are humans because they cooked: namely that we evolved into our present bodies (small mouths, short guts…) over the cinders. Of course, even if we accept this argument – and it is compelling – then we don’t know how much food was cooked. Many things will have been eaten raw for convenience, taste or tradition.
The four points of easy consensus is that hunter-gatherers did not eat starchy rich carbs in any great quantity: they would only begin to do this with the advent of agriculture. So if you wanted to recreate a hunter-gatherer diet grains, for instance, are absolutely marginal. Second, hunter gatherers did not drink alcohol, which arrived at about the same time. No wine, no beer, no spirits… Third, hunter-gatherers did not eat dairy fats: that would come with the so-called ‘secondary products revolution’ and then only in some parts of the world. The far east seems to have never eaten much dairy, for instance. Forget then yogurt, cheese, butter, milk… Fourth, sugar consumption was far inferior to ours: honey was rare, sugar cane was restricted to small parts of south-eastern Asia (and anyway not refined). The result is that it is easier to say what hunter gatherers did not eat than the proportions of what they actually ate. It is the proportions that are the real spanner in the science of the Paleolithic diet: and as suggested above perhaps it is unhelpful to look for them given the amount of variance.
Then, there is another problem. Evolution means that nothing ever stays still. Yes, in our ‘natural state’ as primates we should be fighting saber tooth tigers and eating tree caterpillars. But is that still our ‘natural state’? If you live in Iraq today and you can trace your bloodline in that region, your ancestors have been eating grains for the past two hundred to three hundred generations. There is clear evidence that a change from a hunter-gatherer to a farmer’s diet damaged health initially. But in the long run the evidence ebbs away. In Darwinian terms there is (horrible word) ‘winnowing’: those whose biology reacts against the new diet died earlier and were less likely to pass their genes on to the next generation. In a hundred generations or two hundred generations this has had an impact on the survivors’ tolerance for different kinds of food. Biologists argues about how long it takes for natural selection to have an impact on a given population but the proof of the relevance of human food choices can be found in medical data. For example, celiac condition (where there is an allergy to gluten) grows in western Euro-Asia the further you go from the Fertile Crescent (where wheat was first grown): someone of Irish ancestry is more likely to be celiac than someone of Balkan ancestry. Lactose intolerance grows the further you go from traditional dairy areas in Euro-Asia-Africa: e.g. northern Europe and north-eastern Africa. In other words we are not strictly speaking digital human beings in a caveman’s body. Our bodies are the result of hundreds of generation of choices after our palaeo ancestors had become farmers: choices that, of course, we had no say in.
So how do we determine what is best for us to eat? A useful first principle, and one that pays dividends in health, relationships, and every other sector in our lives is to remember that we are individuals. Our genetic heritage means that our ancestors ate and very possibly benefitted from eating certain kinds of foods. For example, much is made of the Mediterranean Diet as a healthy diet. But there is a real possibility that if you have ancestry from the regions that have eaten the classic Mediterranean Diet as defined by Ancel Keys (Greece and much of Italy) and that have done so for the previous three thousand years (admittedly a brief period in human evolution) then you will be more predisposed to that diet than, say, a Bolivian. Little research has been done on this question, perhaps not least because, in the hands of idiots or racialists, this all could be given a very unpleasant edge. (I take for granted that race is a social construct and that what matters are genes that can still be usefully profiled in groups in some parts of the worlds.) Ethnicity is difficult to trace for most of us today, particularly for anyone whose family has lived for more than two generations in the Americas. The only sensible approach is not to read books or online articles about nutrition but to actually read our bodies as we eat: in any case our genetic heritage is not the only variable. What makes us break out in spots or mouth ulcers; what upsets our digestive system; what depresses us or makes us dozy?
And returning to the original question does it make sense to go on a Paleo diet? Well, there are three obvious benefits. First, the ritual change of foods, dietary placebo, may bring us a sense of well-being: it will certainly concentrate our minds on the rhythms and feelings of our bodies that is hardly a bad thing. Second, the disappearance of dairy and grains may or may not be good for us but they are unlikely to do any harm: and if they are part of a year or a decade long search for what is really good for us as individuals, a learning experience, this is surely to be commended. Third, the one indisputably great thing about the Paleo diet, like the Mediterranean Diet and several other historical diets is that they mean avoiding industrialized food. The diet of most men, women and shamefully children in western societies are disappointing enough that any step in that direction stands as an improvement. In fact, we spend so much time worrying about how we should eat or the magical formula that we forget that there is much in our diet that could be easily dispensed with immediately. (Beach is reminded of a friend who used to lose weight by putting diet coke in her Bacardi.) In short, becoming a dietary caveman is not the worst choice open to a modern man or woman, particularly if it is a transitory choice en route to a more nuanced personal dietary regime.
Other thoughts on the paleo diet: drbeachcombing At yahoo DOT com
5 May 2016: Bruce writes in, ‘I’ve known a doctor, originally from Syria for nearly forty years. When I met him he was about six feet tall and three hundred pounds. He’s stayed about the same size over the years. About a decade ago, he got divorced and discovered the world of gold digging bimbos into which he jumped feet first. Since then it’s been series of diets trying to stay in the game. If a trendy diet came along that made scientific sense to his hormone addled brain he was on it. All were failures.
Roughly three years ago, he discovers the Mediterranean Diet. He couldn’t believe he’d missed it, all the favorite foods of his childhood, it was bound to be a lock. The Doc didn’t bother to weigh himself, he felt so much better. When he finally did he found he was over three hundred and forty pounds and gaining.
If the Mediterranean diet isn’t going to work for a MD from Aleppo, regional and historical fad diets aren’t likely to work for anyone else.’
5 May 2016: James writes in ‘Just a thought: I think they ate whatever they could get their little paws on that didn’t kill them and didn’t taste too bad.Gendered?!?!? Well it is accepted that almost all prehistoric children were birthed by women with the exception of course of Scotland, hence the true reason for kilts.
5 May 2016: LTM on Walt Whitman and the Paleo diet. I hadn’t seen this one coming.