There is a similar phenomenon among the low carb community which disturbs me, since I've been academically trained in both the study of Anthropology (bachelor's degree, University of Chicago) and History (Masters Degree, University of Massachusetts studying under Stephen B. Oates). There is enough data here and now to support the utility of cutting the carbs out of our diet that we don't have to invent an idyllic past to support it.
The two Idyllic Fantasies that bother me the most are these: a) The Paleolithic Perfection scenario and b) The idea that Heart Disease was unknown until very recently. Let's have a brief look at why neither of these arguments are accurate or relevant to us today.
"Paleolithic" refers to all hominids--Neanderthals and modern humans--living before the discovery that plants could be domesticated which took place around 12,000 BC. In the fantasy, Paleolithic people lived on game, ate low carb diets, and were far healthier than everyone ever since.
The fallacy here is that we know very little about real Paleolithic life. All we have are a very limited collection of burials and stone tools with the occasional find of traces of fiber, fossilized seeds, and non-human bones which may or may not be the remains of the hominid meals, since animals often deposit kills in the caves where hominids dwelled at some other time. Most of our beliefs about "paleo" peoples derive from study of isolated groups of early 20th century hunter/gatherers. How similar their habits were were to paleo people of 20,000 years ago is impossible to know.
The argument is made that skeletons of agricultural people from the next, Neolithic, period are shorter than those of the Paleolithic period and show signs of disease not found in the earlier bones. Attributing this to diet makes us feel good about our low carb eating, but it ignores a few key facts: The paleolithic lifestyle winnowed out all but the most healthy and robust very quickly. Human population in the paleolithic period, though it lasted almost 2 million years stayed nearly constant--hominids just barely managed to replace themselves even though females were probably having a baby every 3 years. That's because most babies, all but the most robust--died.
The reason for this is obvious to anyone who has studied the experience modern hunter/gatherer peoples--periodic famine ravaged the population on a regular cyclical basis. The very few hunter/gatherers extant in the early 20th century when they were discovered by anthropologists were those who lived either in extremely isolated environments where agriculture was impossible, or in unusually rich biospheres that made hunting/gathering attractive enough that they did not, like humans in 90% of the rest of the planet, welcome agriculture with wild enthusiasm as soon as they learned of it.
The reason most humans took to agriculture with enthusiasm was precisely because it raised the likelihood of survival. Storing food gets you through famine and allows your children to survive the three months with nothing to eat that otherwise would kill them. It is only after the adoption of agriculture that human population starts to soar.
Those robust skeletons hide another ugly truth. Older individuals or those who have anything wrong with them quickly fall by the wayside when living a migrant paleolithic lifestyle. There is no way a hunting gathering band can carrying along people who can't walk many miles every day. Any severe illness or disability lasting for more than a few weeks will mean that the individual must be abandoned because the group must keep moving to find food. Game isn't stupid and it avoids hunters who stay in one place. Gatherers (i.e. women who supply most of the calories in contemporary hunting/gathering societies) must keep moving because edibles are scarce, seasonal and an area gets picked out pretty fast. So people don't develop the disease of age, like arthritis, because they don't live long enough to do so.
So the apparent "health" of the paleolithic remains is mostly due to the fact that most of the paleo people never made it to adulthood and when they did, they died relatively young--that and the fact that we have very few remains from that period on which to draw our conclusions. Hundreds rather than the tens of thousands from the later period.
The Inuit, so beloved of Paleo fantasists, lived a life of such extreme deprivation that it is hard to understand why anyone would make them the poster child of any diet. While most Native American peoples developed agriculture thousands of years before--the Inuit lived isolated in an environment where it is impossible to grow anything. They did what they could to survive but their numbers were small and their health and that of their children not anything you would envy--their real diet included the stomach contents of their prey--the semi digested vegetable matter now digested since the cellulose had been broken down--and entirely raw meat and fat. No Inuit survived to age 7 who was not metabolically able to cope with that diet. Natural selection works that way.
I urge anyone who romanticizes the Inuit to read The Last Gentleman Adventurer: Coming of Age in the Arctic a fascinating book written by a young man who spent a winter with Inuit living a traditional hunting lifestyle back in the 1920s.
The other fantasy I'm seeing more and more appearing on the health blogs is the idea that heart disease didn't exist until the early 20th century. A good example of this kind of thinking occurs towards the end of this otherwise reasonable blog post: Fat Head: Margarine and Mother Nature. The graph looks impressive, but the reality behind the figures on the graph drains it of the meaning the blogger would like to assign to it.
There are a lot of reasons why heart attack deaths rise. Primary is this: The single strongest epidemiological risk factor for heart attack is age. This is something you don't hear because there is a huge industry devoted to terrifying you, young, about your likelihood of getting a heart attack so it can sell you expensive products and medial services.
But heart attacks have always been relatively rare in people younger than 55. and when they occur they are usually due to specific genetic conditions or side effects of other serious disease processes. Because until the second half of the 20th century a much smaller number of people lived into the decades where heart attacks occur, it should not surprise us that heart attacks were rare.
The reason that Social Security kicks in at 65 is that back when pensions were first instituted (in Germany in the 1880s), not all that many people lived to be much older than 65, so a program that paid pensions to the few rugged survivors was quite economically sustainable. To achieve the equivalent demographic effect today, we would have to raise the age for old age pensions to at least 80, perhaps higher.
People a hundred years ago did not live to die of heart attacks because injury and bacterial infections took a huge toll. An infected pimple could become deadly--my mother remembered children she went to school with dying of just that kind of infection.
Another reason why people did not live long enough to develop heart disease was that until the 1950s there were no effective treatments for high blood pressure so people who developed cardiovascular disease who nowadays might die of a heart attack were much more likely to die of stroke or kidney failure caused by high blood pressure first. When Franklin Roosevelt's blood pressure in 1944 was measured at 210/110 his doctors had no way of lowering it.
The physical labor so adulated by today's gym culture did not lead to a longer life, it wore people out. There is a huge difference between spending an hour or two at the gym and putting in 12 hours six days a week at the steel mill, coal mine, or farm. Physical labor takes a very big toll on the body over time. Add the tuberculosis bacillus to the mix, a disease that preys on overworked crowded populations--or syphilis, one of the most frequent killers in the 19th century, though rarely one that appeared on death certificates, stir in a pinch of cholera, typhoid and other water-borne killers, and you have a very good explanation for the lack of heart disease deaths. Most people didn't live long enough to die of heart attacks.
Heart attacks probably did occur among those lucky enough to make it into their 60s, but in the 19th century and early 20th century differentiating a heart attack from a fatal stroke might have been very difficult. When the death occurred at home as was usually the case, an autopsy would have rarely been performed. When the death involved a person in their 60s or older the diagnosis was likely to be, "Old age."
That people did in fact have nonfatal heart attacks in those times is evidenced by the frequency with which historical sources refer to "dropsy" which sounds a lot like heart failure--the condition that follows nonfatal heart attack. The many older people with "dropsy" probably had serious heart disease. But there was no way of knowing this and when they died of "dropsy," or after a "fit" that was what went on their death certificate.
Finally we should not forget that a major reason for the growth of heart disease in the 20th century was the spread of cigarette smoking which took off after WWI when cigarette manufacturers ensured the troops were given cigarettes along with their rations.
Wikipedia summarizes the epidemiology thus:
The widespread smoking of cigarettes in the Western world is largely a 20th Century phenomenon – at the start of the century the per capita annual consumption in the USA was 54 cigarettes (equivalent to less than 0.5% of the population smoking more than 100 cigarettes per year), and consumption there peaked at 4,259 per capita in 1965. At that time about 50% of men and 33% of women smoked (defined as smoking more than 100 cigarettes per year). By 2000, consumption had fallen to 2,092 per capita, corresponding to about 30% of men and 22% of women smoking more than 100 cigarettes per year, and by 2006 per capita consumption had declined to 1,691; implying that about 21% of the population smoked 100 cigarettes or more per year.In fact, with all the horrors of the modern diet, heart attack death rates in the age group most prone to heart disease have been dropping steadily over the past two decades. This is largely due to anti-smoking efforts and the advent of effective blood pressure medication.
There is no question that cutting down on carbohydrates makes a huge difference in the health of people with diabetes and pre-diabetes. There is no question either that the frankenfood industry is selling products full of highly unhealthy lab created chemicals to an unwary public, and that some of these foods, like the margarine described in the blog post cited above, do worsen our health.
But let's not fall into the trap of imagining that over all health was better in the past and that the reason for this was dietary. For most of human (and hominid) history, food was scare and hard to come by. Starvation was always a possibility. For anyone dwelling in the latitudes where winter brings snow, six months of the year were the "starving time" and agriculture was all that made it possible for large populations to colonize those areas successfully.
Living long enough to develop the "diseases of civilization" was, in many ways, a triumph. You have only to look at the curve of population over the past twenty thousand years to see, in evolutionary terms, which diet and lifestyle made people the most successful in terms of reproductive success.
Diet is an important tool for controlling diabetes, but it is not a panacea, and there is a huge understandable, human tendency to hope that by controlling what we can control--the food we put into our mouth, we can somehow live forever. Those of us with diabetes actually do have a condition where what we eat makes a huge difference in our health outcome but most other human ailments, however, do not fall into this pattern.
Let's do what we can to improve what we eat. Let's avoid foods that obviously harm us, but let's not resort to fantasy and nostalgia to back up our dietary arguments. There is plenty of good data in the present to do so.
Making inflated arguments, or imposing "truths" that are true only for those of us with disrupted glucose metabolisms on everyone blows up in our face. The main reason so many studies of the effectiveness of the low carbohydrate diet come up with tepid (though positive) results is that they involve groups of people that do not have blood sugar problems, for whom the low carb diet is not any more effective than other diets. Were researchers to evaluate the low carb diet as a treatment only for people with abnormal glucose, not as a panacea for all humans including the majority whose glucose metabolism is normal, we'd end up with much more compelling data.
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