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Longing for a past that never existed

There once was a time when all food was organic and no pesticides were used. Health problems were treated with folk wisdom and natural remedies. There was no obesity, and people got lots of exercise. And in that time gone by, the average life expectancy was … 35!

That’s right. For most of human existence, according to fossil and anthropological data, the average human life expectancy was 35 years. As recently as 1900, American average life expectancy was only 48. Today, advocates of alternative health bemoan the current state of American health, the increasing numbers of obese people, the lack of exercise, the use of medications, the medicalization of childbirth. Yet life expectancy has never been longer, currently 77.7 years in the US.

Advocates of alternative health have a romanticized and completely unrealistic notion of purported benefits of a “natural” lifestyle. Far from being a paradise, it was hell. The difference between an average lifespan of 48 and one of 77.7 can be accounted for by modern medicine and increased agricultural production brought about by industrial farming methods (including pesticides). Nothing fundamental has changed about human beings. They are still prey to the same illnesses and accidents, but now they can be effectively treated. Indeed, some diseases can be completely prevented by vaccination.

So why are advocates of alternative health complaining? They are complaining because they long for an imagined past that literally never existed. In that sense, alternative health represents a form of fundamentalism. Obviously, fundamentalism is about religion and the analogy can only go so far, but there are several important characteristics of religious fundamentalism that are shared by alternative health advocacy. These include:

  • The desire to return to a “better” lifestyle of the past.
  • The longing for a mythical past that never actual existed.
  • An opposition to modernism (in daily life and in medicine).
  • And the belief that anything produced by evolution (or God, if you prefer) is surely going to be good.

Advocates of alternative health bemoan the incidence of diseases like cancer and heart disease without considering that they are primarily diseases of old age. That both cancer and heart disease are among the primary causes of death today represents a victory, not a defeat. Diseases of old age can become primary causes of death only when diseases of infancy and childhood are vanquished, and that is precisely what has happened.

Alternative health as a form of fundamentalism also makes sense in that it has an almost religious fervor. It is not about scientific evidence. Indeed, it usually ignores scientific evidence entirely. All the existing scientific evidence shows that all of the myriad claims of alternative health are flat out false. None of it works, absolutely none of it. That’s not surprising when you consider that it never worked in times past; advocates of alternative health merely pretend that it did, without any regard for historical reality.

Alternative health is a belief system, a form of fundamentalism, and like most fundamentalisms, it longs for a past never existed. It is not science; it has nothing to do with science; and it merely reflects wishful thinking about the past while ignoring reality.

Posted in: Science and Medicine

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494 thoughts on “Longing for a past that never existed

  1. Samuel says:

    Does this criticism of the ‘average lifespan of 100 years ago’ make sense?
    http://www.youtube.com/watch?v=qHx1b5MFYkg

  2. My understanding is that the vast majority of that difference in lifespan is accounted for by infant mortality and, to a lesser extent, deaths from other childhood diseases. (As you mention, obliquely, above.) Once you made it to adulthood, life expectancy was basically the same for them as it is for us — most people lived to their seventies, which is why the Bible, for example, gives the average life expectancy (in ancient Israel) as “threescore and ten,” or “if they be strong, fourscore.” Not that the authors of Psalm 90 had access to good statistics, but the numbers seem to give a good indication of what was understood to be a normal lifespan at the time.

    So I’m not sure the “they only lived to 35!!!” argument is really useful. There’s nothing wrong with lauding our modern accomplishments, but there’s also nothing wrong with critiquing some new developments as being less conducive to health than things that were done in the past.

    And many things are mixed blessings. Modern agriculture — and especially modern agricultural policy — makes food available cheaply, but the cheap stuff is mostly BAD food. We could change that situation, and in the process reduce the risk of diseases like diabetes (NOT a disease of old age these days).

    So why not look at human evolution as a guide to what kind of food we likely evolved to eat, and use that understanding as part of a scientific evaluation of nutrition? What’s wrong with pointing to our evolutionary history as an explanation for why vegetables and lean meat are better for you than Twinkies and Froot Loops? The past has a role to play in our understanding of the present — and hence in the shaping of policy.

    Also, I’m not sure that lifespan alone is the only valid indicator of where we’re at as a society. You say that the past was “hell” — is that really true? In all times and all places? You can’t imagine someone coming from some past — any past — looking at modern America, and deciding to return to their own time? Really? The past may not have been a golden age, but it doesn’t follow from that that we have nothing to learn from it.

    Is it not possible, and reasonable, to say that human lifespan has been greatly increased by childhood vaccination and other useful medical interventions, but also that our average lifespan (not to mention happiness) could be increased still further if, for example, we tried eating and working and living in a manner more in line with our biology? Why are those two things contradictory?

  3. Dash says:

    Basically he’s saying life spans haven’t really increased, it’s just that lots of children used to die. Personally, I think children surviving is a pretty good indication that we have a healthier population! Or, as Amy says, we are now able to cure or prevent the things that children used to die from, something that ‘ancienct wisdom’ couldn’t do.

    From a completely anthropological point of view – life expectancy in ancient populations isn’t worked out from a mean of the whole population, it’s worked out from the tiny percentage of fossils we find. So the majority of skeletons are in their 30s, giving us an average life expectancy around 35. I’m out of date here, I haven’t done anthropology in several years, but I doubt the method has changed much.

  4. beatis says:

    This is not the first instance in history where we see a strong longing for a better, more “natural” world.

    The Industrial Revolution saw the rise of the romantic movement, in which the role of man in Nature was evaluated and strongly criticized and an essential ingredient was a strong desire for a way of life that was pure and “natural.”

    Quite a number of thinkers – one of them being Alain Finkielkraut – have argued that the roots for various kinds of fundamentalism lie in the idealism of the romantic movement, for example the “Volksgeist” and the “gesundes Volksempfinden,” important principles of the romantic movement in Germany which have inspired national-socialist thinking and can still be seen today in various political circles. I consider the concept of the “mommy instinct” as a branch of this tree.

    Ruth Scurr in her book “Fatal Purity” has written about the ideals of the French Revolution, which were inspired considerably by the philosophy of proverbial romantic JJ Rousseau and how these ideals could lead to a reign of terror.

    Finkielkraut, Scurr and many others have argued convincingly in my opinion that fervent idealism, i.e. an intense desire for purity – be it religious or otherwise – is often paired with with intolerance and bigotry and carries the seeds of terror.

  5. KGelling says:

    A quick check of the internet for Infant Mortality Rates in the 1800s threw up these two figures – 3/10 infants died before the age of 1 and 50% of children died before adulthood. Although appalling, this is probably in line with mortality rates in other ape and primate species.

    Medicine’s great achievement has been to stop children dying.

    But what was the average lifespan of *those that survived to adulthood*?

    A quick ‘back of a fag packet’ calculation suggests that to achieve an overall average of 35, the remaining 5 (of 10) adults had to have reached 70 years of age.

    The female menopause, which kicks in at 50, is also evidence that our ‘time gone by’ relatives lived well passed 35.

  6. beatis says:

    I have not worded my previous comment accurately enough; I don’t mean to say that “mommy instinct” equals national-socialism, but that it is part of the way of thinking that consistently overvalues “natural” vs “scientific”.

  7. BillyJoe says:

    “Does this criticism of the ‘average lifespan of 100 years ago’ make sense?
    http://www.youtube.com/watch?v=qHx1b5MFYkg

    :D

    This video reminds me of a Monty Python skit but in reverse.
    You know the one: “What have the Roman’s ever done for us”

    As long as you take out all the people who died early, people in the 1900s lived just as long as we do today.

    Good one. ;)

  8. Stroh says:

    It’s very simple to disprove the modern-medicine-does-us-nothing-good-fallacy even by anecdotal evidence. Simply ask yourself: have I ever been seriously ill? If yes, odds are you would already be dead if you had lived in the 19th century.

    I’m among those people. I suffered a bad case of mononucleosis when I was six years old, bad enough to put me on IV for several days. It took me months to recover the lost weight. Would I be alive today without SBM? Perhaps. But probably not.

    If you have never ever been seriously sick, then congrats: you might have lived on to a ripe old age even in the 1800s. But to extrapolate incredible fortune or genetics to the extent that all medicine is futile is incredibly shortsighted and selfish. Most of us are not that lucky!

  9. beatis says:

    My previous comment makes no sense as the original comment is held for moderation. Sorry.

  10. Zoe237 says:

    “Today, advocates of alternative health bemoan the current state of American health, the increasing numbers of obese people, the lack of exercise, the use of medications, the medicalization of childbirth. Yet lifespan has never been longer, currently 77.7 years in the US.”

    As usual, this post is as overly simplistic as the “all nature is pure” folks’ viewpoint. It might help if you had a specific example.

  11. thehandsomecamel:

    ” Once you made it to adulthood, life expectancy was basically the same for them as it is for us — most people lived to their seventies”

    Although infant and child mortality is responsible for a very substantial proportion of deaths in nature, there is no evidence that most people lived into their seventies. Just consider what we know of historical figures. How many historical figures (generally the best fed and the most well off people in their societies) attained the age of 70?

    Consider that while Presidents Adams and Jefferson lived to an advanced age, William Henry Harrison died of pneumonia only 10 days after his inauguration. Queen Elizabeth lived into her 60s, but her brother Edward died of tuberculosis at the age of 16, her uncle Arthur, the Prince of Wales, died in his late teens of an unspecified illness, and her sister Mary died of unknown causes in her early 40s. Some of the ancient philosophers lived to old age, but Alexander the Great died of an infectious disease at age 33.

    Medical advances have had the greatest impact on disease of childhood, but the impact on diseases of adulthood has been substantial. Who dies of tuberculosis these days? How about dysentery, smallpox, or even plague?

    Malnutrition was endemic, almost always compromising health. For most of human existence, and in some places to this very day, human beings have faced periodic severe food shortages, permanently stunting growth and creating additional health problems. At the simplest level, very few people were able to keep their teeth into middle age, let alone survive that long.

    Hobbes was talking about politics when he wrote that life in the state of nature was “solitary, poor, nasty, brutish and short” but his words are equally true of health conditions.

  12. thehandsomecamel:

    “So why not look at human evolution as a guide to what kind of food we likely evolved to eat, and use that understanding as part of a scientific evaluation of nutrition?”

    Because that’s a naturalistic fallacy. There is no reason to think that what we ate was the ideal diet; it was merely the available diet.

    The insights being gained from the field of evolutionary medicine contrast dramatically with the evolutionary claims of “alternative” health advocates. It is axiomatic in “alternative” health that the human body represents evolutionary perfection and that if we only hark back to nature we will be healthier. Evolutionary medicine, in contrast, recognizes that the human body is the result of competing evolutionary pressures and changing pressures of natural selection.

    Moreover, the critical driver of evolution, natural selection, does not favor perfection or even health; it favors reproductive success and it tolerates a massive amount of wastage. The most “successful” human beings in evolutionary terms are those that leave the most offspring, not those that live the longest.

    This is what I mean when I refer to “longing for a past that never existed.” It is simply a myth that life in the state of nature was “perfect” or even tolerable.

  13. “Quite a number of thinkers – one of them being Alain Finkielkraut – have argued that the roots for various kinds of fundamentalism lie in the idealism of the romantic movement, for example the “Volksgeist” and the “gesundes Volksempfinden,” important principles of the romantic movement in Germany which have inspired national-socialist thinking and can still be seen today in various political circles.”

    Karen Armstrong, who has written extensively on religious fundamentalism, has emphasized that religious fundamentalists idealize the past in similar ways and consider themselves to be returning to that past. Of course, that past never existed.

  14. Scott says:

    The post would be strengthened by an examination of the evidence that shows ancient life expectancies. The people I know who take this perspective insist that life expectancies in hunter/gatherer societies were 100+ years, and that while medicine has increased them drastically over the past 100 years, that’s only partially making up for the horrible health effects of civilization.

    When pressed, they can’t provide any actual EVIDENCE for that proposition, of course. But in my experience the sticking point is precisely what was simply asserted without any detailed discussion – “For most of human existence, according to fossil and anthropological data, the average human lifespan was 35 years.”

  15. mxh says:

    Great post. This reminds me of a presentation I attended by a dermatology resident who was into all natural treatments (not sure how she got into derm). She said that using soap daily is unnecessary, claiming that all it does is damage our skin. She pointed to our prehistoric ancestors and said that they were fine without using soap. She ended her presentation with “and how was their health different from ours.” Expecting everyone to say not much, she was a little shocked when I shouted, “They died at 30.” Got a nice laugh from the audience.

  16. bluedevilRA says:

    Stroh raises a good point. The problem is, most people don’t even realize when they receive treatment for life threatening diseases.

    Secondly, the “we evolved to eat only what we could hunt and gather” gambit is a ridiculously romantic portrayal of early humanity. Sure, hunting and gathering sounds fun. Who wouldn’t want to gather food with Racquel Welch in 10,000 BC? But unfortunately, that is not reality. Reality is starvation, scavenging, and scurvy. As Dr. Tuteur aptly states, we evolved to eat what was available. There was no choice involved in the matter.

    Furthermore, this argument that we evolved to only eat pre-civilization food is a complete misunderstanding of evolution. We *evolved* the use of tools and the development of agriculture. This has made us fitter as a species. Fitness is about the production of successful offspring and the population boom in the last 100 years has clearly shown that the evolution of agriculture benefited us as a species.

    In fact, the development of agriculture is arguably the greatest accomplishment of the human species. It enabled us to create cities and the specialization of labor, which subsequently allowed us to to develop modern science and medicine.

  17. LovleAnjel says:

    Amy, citing a royal family of Europe as “the most likely to live long” is probably a bad idea, since they were terribly inbred and had many people gunning for their thrones. Medieval medicine being what it was, on some level I’d rather be a peasant without a doctor than nobility with someone who will bleed me repeatedly and make me take gross, unproven remedies.

  18. Alex Knapp says:

    What a disappointing post in what is overall a wonderful site. When I come to SBM, I’m used to seeing citation to peer-reviewed research and analysis. I’m used to a thoughtful consideration of points. Not just polemic.

    This point is particularly bad:

    The difference between an average lifespan of 48 and one of 77.7 can be accounted for by modern medicine and increased agricultural production brought about by industrial farming methods (including pesticides).

    While it’s true that modern medicine has improved life expectancy, particularly for infants and children, the idea that agriculture is an unequivicol good from a medical standpoint simply lacks support. The archaeological evidence suggests, for example, an almost uniform crash in average heights when populations make the transition from hunter-gatherer to agriculture (in Crete, for example, average heights for men went from 5’9″ pre-agriculture to 5’3″ afterwards).

    Anyone familiar with contemporary medical literature at the turn of the 20th century also knows that native African and Asian populations suffered very little from diseases such as diabetes, cancer, heart disease and cavities, but saw rapid increases in all of these diseases upon the adoption of the Western “industrial agricultural” diet.

    So it’s impossible to state that the difference in life expectancy is due to BOTH modern medicine AND industrial agriculture. Not without a study that compared groups of people with access to modern medicine, but with one living on a traditional diet and the other on a diet of food produced by “industrial farming methods.”

    Absent that study, you can have an opinion, but it won’t be a science-based one.

  19. Zoe237 says:

    Actually, the movie Avatar could be used as an example in popular culture. Basically, a Native American civilization on another planet are portrayed as the good guys, while the evil technology driven armed forces attempts to exterminate them. As the highest grossest movie of all time, I think it’s relevant to where we’re at as a culture. Historically speaking, nature vs. science is a very interesting push-pull, with people on both extremes. Both sides use life expectancy through history as some sort of “proof” for their false cause associations. In essence though, it’s kind of like nature vs. nurture, or phonics versus whole language.

  20. Galadriel says:

    Something I find as an interesting snapshot of the state of health pre-modern medicine is to open up Wikipedia to a page on someone I find interesting…then to look at what we know of that person’s family. This is hardly rigorous nor is it an impeccable source, but it does, I think, provide some insight.

    Take, for example, the Bronte sisters. They were 3 out of 6 children. Their mother died of cancer, age 38. The two oldest children died of tuberculosis age 9 and 10. The one brother died of tuberculosis age 31. Emily Bronte died (TB) age 30, and so did Anne. But hey, Charlotte lived to be 38! She died during pregnancy, either of typhus or a pregnancy-related condition. Their father outlived them all, living to the age of 84.

    So sure, yeah. If early childhood illness didn’t get you, and early adulthood illness didn’t get you, and middle age illness didn’t get you, you certainly could live to a ripe old age.

  21. Zoe237 says:

    “Fitness is about the production of successful offspring and the population boom in the last 100 years has clearly shown that the evolution of agriculture benefited us as a species.”

    I agree that agriculture benefitted us as a species. I would go back even further, to the Neolithic revolution, around 10,000 years ago, (if we’re looking at hunter-gatherer societies versus farming), when population started growing exponentially.

    Of course, the advent of agriculture wasn’t all good. Smallpox, for example, became widespread, and the hunter gatherers (along a few groups were farmers, but not of livestock) of North America were decimated by it. Other diseases also became more widespread because people lived closer together in one spot. Tradeoffs.

    Jared Diamond’s book “Collapse” talks about some of the “one with nature” myths about traditional societies.

    The National Academy of Scienes series Dr. Novella posted about a few weeks ago on evolution has some really cool articles on aging and disease.

  22. David Gorski says:

    My understanding is that the vast majority of that difference in lifespan is accounted for by infant mortality and, to a lesser extent, deaths from other childhood diseases. (As you mention, obliquely, above.) Once you made it to adulthood, life expectancy was basically the same for them as it is for us — most people lived to their seventies, which is why the Bible, for example, gives the average life expectancy (in ancient Israel) as “threescore and ten,” or “if they be strong, fourscore.” Not that the authors of Psalm 90 had access to good statistics, but the numbers seem to give a good indication of what was understood to be a normal lifespan at the time.

    While it’s certainly true that declining infant mortality and conquering of childhood diseases were huge factors in increasing life expectancy, adult life expectancy has been increasing as well. For example, John Graunt reported on life expectancy in London in the 1500s and 1600s, one of the earliest examples of vital statistics. In 1662, he published Natural and Political Observations Mentioned in a Following Index and Made Upon the Bills of Mortality. In this book, Graunt was the first to attempt to construct life tables and mortality tables based on the numbers of births and reported deaths in London. As a tercentenary tribute stated:

    300 years ago John Graunt, a London draper, published some “Natural and Political Observations on the Bills of Mortality.” These observations represent the 1st, as well as an extremely competent attempt, to draw scientific conclusions from statistical data. The present study illustrates Graunt’s careful scientific approach, his ability to extract the essence from what by modern standards are distinctly untrustworthy demographic data, and his intuitive appreciation of the amount of interpretation his findings would tolerate. Based upon ratios and proportions of vital events and consideration of the way in which these changed in different circumstances, his analysis is amazingly free of major statistical errors. His statistical understanding was consideration. He is responsible for the 1st scientific estimates of population size, the concept of the life table, the idea of statistical association, the 1st studies of time series, and a pioneer attempt to draw a representative sample. Graunt’s book continued to be worthy of reading today, for it laid the foundations of the science of statistics.

    So what did John Graunt find?

    Graunt found that the average life expectancy in London was 27 years, with 65% of people dying before age 16, the vast majority due to childhood infectious diseases, diseases, I note, that have now been largely brought under control by vaccines, antibiotics, and advances in medical care. Steve Rappaport reports in Worlds Within Worlds: Structures of Life in Sixteenth-Century London that, a century earlier in the 1500s, of men who made it to age 25 to 26, the ages at which most men became full citizens, the average further life expectancy was 28 years, meaning that men who made it to adulthood would have had about a 50-50 chance of living to be older than 53 or 54. One-tenth died by their mid-30s, and only around one-third lived to be older than sixty. I’m not quoting these statistics for precision, but merely to show that life expectancy sucked until fairly recently even for adults. Only about 1/3 of people who made it to their 20s made it to age 60, and many fewer still to age 70 or 80, about 12-15% and 2-3% respectively. (I’m guesstimating from looking at a graph in the book.) In all fairness, I note that life expectancy was significantly higher in the countryside, at least as far as the data we have suggest. Still, people who lived to adulthood did not make it to their 70s and 80s at anywhere near the rate that they do now.

  23. rosemary says:

    Scott, “But in my experience the sticking point is precisely what was simply asserted without any detailed discussion – ‘For most of human existence, according to fossil and anthropological data, the average human lifespan was 35 years.’”

    Coming up with solid evidence about what things were like in the past, especially evidence that is meaningful to the general public, is very difficult. The further back you go the more difficult it becomes. However, there is a lot of evidence in our very recent past, even in my experience and that of the generation that preceded me, which is very convincing. Some examples, my maternal grandparents both died in their 40s in the 1930s, one from a stroke probably caused by hypertension, the other from pneumonia. Several other relatives died prematurely from TB. I personally remember the polio epidemics. Before you start shouting ANECDOTES!!!, I’d like to point out that I’m pretty sure you can find very reliable statistics about the number of deaths caused by these diseases in the not so distant past. I had breast cancer in 1984. My cousin has had Type 1 diabetes since childhood. She is now in he 50s. What do you think would be the odds of our being alive today without scientific medicine? How about my dog who has hypothyroidism? Want me to go on? I haven’t gotten to my cats yet.

    mxh, referring to a dermatologist, “She pointed to our prehistoric ancestors and said that they were fine without using soap.” She gave a citation right? From the Prehistoric Journal of Dermatology, maybe? Doesn’t anybody read anymore? Off the top of my head I can remember reading about a young Polish girl deported by the Russians along with many other Poles to Siberia during the Second WW where there was no soap, Cambodians living without soap and British nurses held prisoners by the Japanese during WWII who didn’t have any. They weren’t “just fine” and neither was their skin. Of course, they also suffered from other things which could affect their skin, such as, in some cases malnutrition or just very poor diets. While it would take studies to determine, whether or not, or to what degree, the lack of soap was responsible for their skin diseases, if I remember correctly, all really missed soap and were very happy when it was again available. IMO, even that pleasure should account for something that even the prehistoric derm should recognize as valuable.

    I think that one of the main reasons that the past is romanticized by so many in the general public is because in addition to having no education in science, they also lack any in history and they seem to do very little reading. In GROWING UP, by Russell Baker, starting on p. 50 he has a few very informative pages about life and death in backwoods America in the 1920s before scientific medicine reached there. Just one quote from p. 52, “In Morrisonville death was a common part of life. It came for the young as relentlessly as it came for the old. To die antiseptically in a hospital was almost unknown. In Morrisonville death still made house calls.”

  24. bluedevilRA says:

    Alex Knapp, for being so critical of Dr. Tuteur’s lack of citations, you do a poor job yourself. Please include a citation for us to review the Crete archaelogical evidence.

    Further, the ability to accurately diagnose coronary artery disease (which is the form of heart disease you seem to be claiming comes from a poor diet) was not developed until the late 1950′s or early 1960′s via use of cardiac catheterization. We cannot retroactively determine the prevalence of CAD from hundreds of years ago.

    However, we know that CAD typically affects men over 60 and women over 65. If people died before that age, then of course CAD would be rare. They wouldn’t reach the age to develop clinically significant occlusions in their coronary arteries!

    Diagnostic problems apply to cancer as well. How do you know cancer did not exist? We weren’t very good at identifying cancer before the development of modern medicine.

  25. “While it’s true that modern medicine has improved life expectancy, particularly for infants and children, the idea that agriculture is an unequivicol good from a medical standpoint simply lacks support. The archaeological evidence suggests, for example, an almost uniform crash in average heights when populations make the transition from hunter-gatherer to agriculture (in Crete, for example, average heights for men went from 5′9″ pre-agriculture to 5′3″ afterwards).”

    The best measure of evolutionary success is population growth, and by that measure, agriculture was an extraordinary triumph. Prior to the advent of agriculture, human populations were probably measured in the tens of thousands, dropping as low as 10,000 individuals during certain times of hardship. In contrast, agriculture allowed for a population explosion that has been continuing to this day. Medicine has allowed for an acceleration of that population explosion.

    “Anyone familiar with contemporary medical literature at the turn of the 20th century also knows that native African and Asian populations suffered very little from diseases such as diabetes, cancer, heart disease and cavities, but saw rapid increases in all of these diseases upon the adoption of the Western “industrial agricultural” diet.”

    Diabetes (type II), cancer and heart disease are predominantly diseases of old age. The rise in incidence of these diseases is a sign of SUCCESS, not failure. When the average life expectancy is low, the rate of chronic diseases of old age is low. When the average life expectancy rises, the incidence of diseases of old age rises too. That’s hardly a bad thing.

    As for the incidence of cavities, that’s a bunch of baloney.

  26. “I think that one of the main reasons that the past is romanticized by so many in the general public is because in addition to having no education in science, they also lack any in history and they seem to do very little reading.”

    Absolutely. In addition, as a culture we tend to disparage history. The expression “that’s history” means “that’s irrelevant” so people often ignore history. When people know very little history, they tend to imagine that the way things are today is the way that they always were. Nothing could be further from the truth.

  27. Alex Knapp says:

    @BluedevilIRA -

    Please include a citation for us to review the Crete archaelogical evidence.

    My mistake – it was Greece and Turkey, not Crete. Citation is from a 1987 article by Jared Diamond. Full copy of the article can be found here:

    http://jeffweintraub.blogspot.com/2005/09/jared-diamond-on-why-invention-of.html

    Further, the ability to accurately diagnose coronary artery disease (which is the form of heart disease you seem to be claiming comes from a poor diet) was not developed until the late 1950’s or early 1960’s via use of cardiac catheterization. We cannot retroactively determine the prevalence of CAD from hundreds of years ago.

    No, but you can look at turn of the century comparative research on heart attacks of native v. western populations within the same region. Ditto for cancer. They may not have had the best cancer diagnostics in the 1920s, but they could and did find tumors during autopsy, and they could and did compare the prevalence of tumors in the “native diet” v. “western diet” among the same population in the same region. I have cites in my other office but not on the computer I’m working from now. If I get a chance, I’ll post those citations.

  28. Sid Offit says:

    Amy you’re clueless. A reduction in infant mortality is responsible for any increase in average lifespan and that increase had nothing to do with any of your imagined medical miracles – unless you believe not drinking filthy water to be a medical miracle

  29. “A reduction in infant mortality is responsible for any increase in average lifespan and that increase had nothing to do with any of your imagined medical miracles”

    Sid, you’re just the kind of person about whom I am writing, those who imagine an idealized past without bothering to acquire any knowledge of what the past was actually like.

    How about some scientific evidence in support of your claim? Surely you have something to offer besides your personal opinion.

  30. rosemary says:

    Alex Knapp, “So it’s impossible to state that the difference in life expectancy is due to BOTH modern medicine AND industrial agriculture. Not without a study that compared groups of people with access to modern medicine, but with one living on a traditional diet and the other on a diet of food produced by ‘industrial farming methods.’”
    Absent that study, you can have an opinion, but it won’t be a science-based one.”

    I disagree and think this is an example of the problem of using SBM as opposed to EBM to evaluate health interventions. (Yes. I realize that I may not correctly understand what is meant by EBM although from a quick glance I suspect that it isn’t written in stone and that different institutions give it different definitions.) If I understand Alex’s interpretation of SBM, the lack of one very high quality study controlling for all variables, means that there is insufficient evidence to draw any reasonable conclusion. That is where I disagree. I think there are degrees of evidence which provide us with levels of certainty on a continuum with the kind of study he says we need at one end and opinion at the other.

    I suspect that there is a lot of evidence that shows that before the introduction of “modern methods” of farming, many people died of starvation because enough food could not be produced the old way. (The Irish Potato famine comes to mind.) If so, the evidence of all those deaths caused by the inability of farmers to feed everyone, is very good evidence that what replaced the old method saved, prolonged and improved a great many human lives. Additionally, countless hours and labor had to be spent growing food the old way prevented people from engaging in other, perhaps more valuable, pursuits.

    I suspect, but do not know, that Alex and others are concerned about the dangers of “industrial farming”. However, I believe that is another topic, one for now and the future, not one to use to measure how science, agricultural science and chemistry, benefited past generations.

    Sorry if I’m not sounding terribly clear, but it is that kind of topic.

  31. Alex Knapp says:

    Amy,

    The best measure of evolutionary success is population growth, and by that measure, agriculture was an extraordinary triumph.

    I didn’t say that agriculture was unequivocally bad. I said that it wasn’t unequivically good. Until the 20th century, humans in agricultural societies suffered more malnourishment and health problems than humans in agricultural societies. But yes, there were more people in agricultural societies. But is mere numbers of people the only measure of health?

    Medicine has allowed for an acceleration of that population explosion.

    I didn’t dispute that, either. I think that modern medicine is a wonderful thing.

    Diabetes (type II), cancer and heart disease are predominantly diseases of old age.

    While the indicence of type II diabetes definitely increases with age in the United States, I have a hard time describing a disease that impacts 10.8% of the population between the ages of 40-59 as a “disease of old age.”

    (see http://diabetes.niddk.nih.gov/DM/PUBS/statistics/#allages)

    Ditto heart disease, which afflicts 7.7% of people between 44 and 65 in the United States. (http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5606a2.htm)

    Additionally, the stuides done between native and westernized populations in the early 20th century were controlled for age and still found lower prevalence of diabetes, cancer, and heart disease in those eating a tradtional diet vs. a western one.

    As for the incidence of cavities, that’s a bunch of baloney.

    It’s well documented that the incidence of cavities is lower in hunter-gatherer populations vs. agricultural populations. See e.g. Cassidy CM. Nutrition and health in agriculturalists and hunter-gatherers: a case study of two prehistoric populations. in Nutritional Anthropology. Eds Jerome NW et al. 1980 Redgrave Publishing Company, Pleasantville, NY pg 117-145, or just this Archaeology textbook (http://books.google.com/books?id=Nw4eqX0pIt0C&pg=PA246&lpg=PA246&dq=cavities+hunter+gatherers&source=bl&ots=n9GN8fd-B8&sig=bVUFLadeezDNbiHGadeDC-B7cw8&hl=en&ei=A2l9S73hGIb08QanwpXDBQ&sa=X&oi=book_result&ct=result&resnum=3&ved=0CAwQ6AEwAg#v=onepage&q=cavities%20hunter%20gatherers&f=false)

    In addition, as a culture we tend to disparage history.

    I think it’s as dangerous to romanticize the present as it is to romanticize the past. We should take as much knowledge as we can and study it in order to live the best lives we can. To blithely assume that modern life is, in every respect, superior to life in the past based on life expectancy alone is ridiculous. There are trade offs in everything. It may be that aspects of life in the past, coupled with modern advancements, would lead to a healthier life. But we’ll never know it unless we study it instead of just automatically assuming that everything we do now is the best way people have ever lived.

  32. Alex Knapp says:

    Rosemary,

    If I understand Alex’s interpretation of SBM, the lack of one very high quality study controlling for all variables, means that there is insufficient evidence to draw any reasonable conclusion.

    I think that, given the available evidence, it’s more reasonable to assume that advances in health are almost solely due to modern medicine and not the industrial methods of farming. I say this because modern farming produces food that is less nutrient dense and higher in sugar content than existed even 50 years ago–to say nothing of extensive medical research in the early 20th century comparing the heath effects of native vs. western diets. As a consequence, I’d have to see a highly controlled study that shows the superiority of a modern diet, because the observational evidence goes the other way.

  33. Sid Offit says:

    @David

    the vast majority due to childhood infectious diseases, diseases, I note, that have now been largely brought under control by vaccines, antibiotics, and advances in medical care.

    —————————

    except these declines all took place before vaccination, antibiotics or “medical care” See Richard Lewontin’s Triple Helix P104-05

  34. Michelle B says:

    I am glad that science based medicine and agriculture did not really make a difference in longevity, because if they did we would have an overpopulated world.

    Lol.

  35. Sid Offit says:

    A reduction in infant mortality is responsible for any increase in average lifespan

    Let me correct myself. Medicine has increased lifespan but not from the fanciful 35 years Amy imagines. Yet without the Western diet, many wouldn’t need medical interventions to survive.

  36. Alex Knapp:

    “But is mere numbers of people the only measure of health?”

    Not the only measure, but one of the best. The unhealthy die prematurely. It’s difficult to be less healthy than when you are dead.

    “I have a hard time describing a disease that impacts 10.8% of the population between the ages of 40-59 as a “disease of old age.”

    But in reproductive terms, age 40 is old age. Consider that childbearing began in the late teens. It is possible to raise several children to their own reproductive age by age 40. Death after that would not be an evolutionary disadvantage.

    Remember, evolutionary success is measured by number of living offspring, not by length of life. Natural selection does not select for health, it selects for reproductive outcomes.

  37. “It’s well documented that the incidence of cavities is lower in hunter-gatherer populations vs. agricultural populations.”

    Not exactly. Although eating cariogenic carbohydrates is a risk factor for developing cavities, it’s not the only factor.

  38. Sid Offit:

    “See Richard Lewontin’s Triple Helix P104-05″

    Sorry, but that’s not a scientific citation. Surely you can do better than that when advancing a claim that is absurd on its face.

  39. Sid Offit:

    “Medicine has increased lifespan but not from the fanciful 35 years Amy imagines. Yet without the Western diet, many wouldn’t need medical interventions to survive.”

    Yes, we know that’s what you believe but you need to provide scientific evidence in order to convince anyone else. Where’s the evidence?

  40. Sid Offit says:

    http://www.cepr.org/pubs/bulletin/DPS/DP121.HTM

    Mckeown effectively demonstrated that advances in medical science, such as the immuno- and chemotherapies which form the basis of today’s clinical and hospital practices, played only a very minor role in the late nineteenth century mortality decline: most of the important diseases involved had already disappeared in England and Wales before the date at which the relevant medical innovations occurred.

  41. Sid Offit:

    “Mckeown effectively demonstrated …”

    No, no, no, that’s not how you support a claim with scientific evidence. You need to quote the relevant passages, discuss the limitations of the study or report, and compare it to the larger body of scientific evidence on the topic.

    Copy and pasting a link, which might impress lay people, carries no weight here.

  42. Alex Knapp says:

    Amy,

    “But is mere numbers of people the only measure of health?”

    Not the only measure, but one of the best. The unhealthy die prematurely. It’s difficult to be less healthy than when you are dead.

    Okay, but now we’re unjustifiably conflating life expectancy with population size.

    I’d highly recommend you read the Cassidy article I cite above, which compared the archaeological evidence of two groups of native Americans in the same region, of which one was a hunter-gatherer society (referred to as “Indian Knoll”) and the other was agricultural (referred to as “Hardin Village”). Here’s the summary of the authors’ findings:

    1. Life expectancies for both sexes at all ages were lower at Hardin Village than at Indian Knoll.
    2. Infant mortality was higher at Hardin Village.
    3. Iron-deficiency anemia of sufficient duration to cause bone changes was absent at Indian Knoll, but present at Hardin Village, where 50 percent of cases occurred in children under age five.
    4. Growth arrest episodes at Indian Knoll were periodic and more often of short duration and were possibly due to food shortage in late winter; those at Hardin Village occurred randomly and were more often of long duration, probably indicative of disease as a causative agent.
    5. More children suffered infections at Hardin Village than at Indian Knoll.
    6. The syndrome of periosteal inflammation was more common at Hardin Village than at Indian Knoll.
    7. Tooth decay was rampant at Hardin Village and led to early abscessing and tooth loss; decay was unusual at Indian Knoll and abscessing occurred later in life because of severe wear to the teeth. The differences in tooth wear and caries rate are very likely attributable to dietary differences between the two groups.

    However, it was true that the population of the agricultrual society was higher. However, it came at the price of a lower overall quality of health. Why can’t we learn from that? Why must we blindly disparage “the past” because they had a lower life expectancy? Why doesn’t this merit more study in a modern nutritional context?

    But in reproductive terms, age 40 is old age. Consider that childbearing began in the late teens. It is possible to raise several children to their own reproductive age by age 40. Death after that would not be an evolutionary disadvantage.

    Why not? Prior to the invention of writing, people over the age of 40 would serve as a repository of knowledge, customs, culture, and stability. This is why elders are revered cultures without a written language, and it may well be that the survival of that knowledge garners an evolutionary advantage to humans. I’m not saying this is true, I’m saying that given that humans are social animals, there may be evolutionary advantages to longer life spans beyond mere reproductive age and accordingly it’s dangerous to write off over 40 as “old” from an evolutionary perspective. Additionally, when comparative studies have been done of people who do not follow western diets, the prevalence of diabetes and heart disease is diminished even among the elderly compared to those with western diets.

    Natural selection does not select for health, it selects for reproductive outcomes.

    I’m sorry, but this is an incredibly simplistic view of evolution that doesn’t take into account selection among social animals, particularly mammals and primates.

  43. Alex Knapp says:

    Amy,

    Not exactly. Although eating cariogenic carbohydrates is a risk factor for developing cavities, it’s not the only factor.

    While that’s true, it doesn’t change the fact that the archaeological evidence demonstrates that the incidence of cavities is lower in hunter-gatherer societies than in agricultural ones. That doesn’t mean that H-Gs have no cavities. Just that they have fewer.

  44. “Okay, but now we’re unjustifiably conflating life expectancy with population size.”

    Unjustifiably? Please explain.

    “which compared the archaeological evidence of two groups of native Americans in the same region, of which one was a hunter-gatherer society (referred to as “Indian Knoll”) and the other was agricultural (referred to as “Hardin Village”). Here’s the summary of the authors’ findings:”

    And why should we believe that the findings of one study about two native American villages can be extrapolated beyond those two villages?

    “this is an incredibly simplistic view of evolution that doesn’t take into account selection among social animals, particularly mammals and primates.”

    I’m not sure what you are referring to. Could you elaborate?

  45. “While that’s true, it doesn’t change the fact that the archaeological evidence demonstrates that the incidence of cavities is lower in hunter-gatherer societies than in agricultural ones.”

    But not in all of them. For example, research from Asia indicates that the switch to a predominantly cultivated rice diet did not result in a deterioration of dental health.

  46. Alex Knapp says:

    “Okay, but now we’re unjustifiably conflating life expectancy with population size.”

    Unjustifiably? Please explain.

    I would argue that a larger population with a lower life expectancy is indicative of worse health, but that’s the pattern we see time and time againt when socieites move from Hunter-Gatherer to Agriculture. It wasn’t until the adoption of modern medicine and santiation that agricultural societies showed greater and more robust health.

    And why should we believe that the findings of one study about two native American villages can be extrapolated beyond those two villages?

    Because the archaeological record is replete with similar stories, as are historical accounts. The Cassidy study I particular recommend because of how comprehensive it is, but it’s far from the only study demonstrating the same result.

    But not in all of them. For example, research from Asia indicates that the switch to a predominantly cultivated rice diet did not result in a deterioration of dental health.

    True, but when they started refining the rice it did.

    I’m not sure what you are referring to. Could you elaborate?

    Among social animals, the survival of individuals is dependent on the survival of the social group as a whole. Children are helpless for the first decade of life, so the survival of genes is dependent on there being a large support network to ensure the survival of children, even if their parents die. Thus, there’s an evolutionary advantage to long-life in humans, because pre-writing, the knowledge and experience of the elderly allowed for knowledge to be used and passed on to enhance the survival of the group and therefore children. Group dynamics also get selected for from an evolutionary perspective. (Van Der Waal has some interesting insights from a group of chimps where the most aggressive males were killed in an accident, leaving the “beta males” behind to reproduce. The result was a much more cooperative, less aggressive social group that ended up having a larger population than similar chimpanzee groups because there was less violence among the chimps.)

  47. Harriet Hall says:

    Amy, while I agree with your main points, I have to question one statement you made: “All the existing scientific evidence shows that all of the myriad claims of alternative health are flat out false.”

    I think it would be more accurate to say that all the existing scientific evidence is compatible with the hypothesis that no CAM treatment works better than placebo, except for some herbal remedies which would probably work even better if they were approached by the time-tested methods of pharmacology with isolation and purification of the active ingredient.

  48. Alex Knapp:

    “The archaeological evidence suggests, for example, an almost uniform crash in average heights when populations make the transition from hunter-gatherer to agriculture (in Crete, for example, average heights for men went from 5′9″ pre-agriculture to 5′3″ afterwards).”

    Accepting this and the implied causal relationship as fact for the sake of argument: Can you provide any support for the notion that a decrease in average height is detrimental in any way other than it makes it harder to reach the top shelf in the kitchen?

  49. bluedevilRA makes a good point as well: “The problem is, most people don’t even realize when they receive treatment for life threatening diseases.”

    You may realize you owe your life to modern medicine if you have/had juvenile diabetes, asthma, certain severe allergies, needed surgery, etc, but…

    Let’s put it this way,

    Have you ever taken an antibiotic?
    Have you ever had a tooth extracted or filled?
    Have you ever applied an topical antiseptic or antibiotic to a cut or open wound?
    Have you ever had a vaccine?
    Had required an injection of epinephrine?
    (This list could go on and on…)

    If so, foregoing any of these would have increased your risk of, if not led directly to, a potentially fatal outcome

    “Reality is starvation, scavenging, and scurvy.”

    Yes, reality in the past also favored survival of those physically strong enough to survive and provide for themselves. In modern times, we consider ourselves better off that people like Stephen Hawking are around to think about things.

  50. wales says:

    Amy said “No, no, no, that’s not how you support a claim with scientific evidence. You need to quote the relevant passages, discuss the limitations of the study or report, and compare it to the larger body of scientific evidence on the topic. Copy and pasting a link, which might impress lay people, carries no weight here.”

    That is a fine list of requirements, but apparently Amy is exempt from these requirements? Or are we to assume that there is no scientific evidence for her post here, since she has not supported her sweeping claims via: quoting relevant passages, discussing limitations of studies and reports, making comparisons to the larger body of scientific evidence and providing citation links?

    Amy’s criticism of Sid is ironic given that his link to an article by Dr. Simon Szreter of Cambridge is relevant, educational and on topic, more so perhaps than the opinions she has generated here. BTW, the emphatic repetition of “no” is best confined to discussions with toddlers.

  51. Alex Knapp says:

    Karl,

    Accepting this and the implied causal relationship as fact for the sake of argument: Can you provide any support for the notion that a decrease in average height is detrimental in any way other than it makes it harder to reach the top shelf in the kitchen?

    All else being equal, stunted growth is typically symptomatic of malnourishment.

  52. wales says:

    Oh I nearly forgot, here’s the Szreter paper that Sid’s link discusses. For those of you who like to consult primary sources anyway. http://shm.oxfordjournals.org/cgi/pdf_extract/1/1/1

  53. “I think it would be more accurate to say that all the existing scientific evidence is compatible with the hypothesis that no CAM treatment works better than placebo, except for some herbal remedies which would probably work even better if they were approached by the time-tested methods of pharmacology with isolation and purification of the active ingredient.”

    Agreed!

  54. bluedevilRA says:

    Thanks for the citations. I will look into them tonight (I’m at work currently).

    Zoe, I didn’t mean to paint the agricultural revolution as one event (I was describing all the agricultural revolutions and advancements that have occurred in human history). Also, I agree that the spread of disease was an unfortunate side effect of the growth of cities, the increase in farm production, and the increase in trade.

    I think the EBM vs SBM debate is very relevant here. The theory put forth by Alex and others seems to be that H-G’s were more fit to survive because they lived long and healthy lives. They had fewer diseases compared to modern man and were therefore superior.

    I believe this theory is clearly debunked by the growth numbers. H-G’s struggled to survive. If they had lived long, happy and healthy lives their population would have grown. It did not.

  55. Alex Knapp:

    “All else being equal, stunted growth is typically symptomatic of malnourishment.”

    Accepting this as fact for the sake of argument, can you provide support for the implied assumption that the reduction in average height you mentioned was a result of stunted growth?

    One other obvious possibility is an increased survival rate for smaller, weaker, less physically gifted, and shorter individuals (assuming height is an indicator of optimal physique) for one reason or another. This could, perhaps, be due to better, more readily available nourishment, or maybe it was due to a lower probability of being killed by one’s prey if you were tall and strong (assuming tall=strong & fit). Without support, my speculation is as valid as yours.

    If you are going to call someone out for not supporting their position with peer-reviewed research and analysis, you’d better make sure your not standing in a glass house when you do it.

  56. There are ways to limit population growth besides having a baby every year and letting half of them die (the agricultural model). My understanding is that in hunter-gatherer societies it is more typical to have a baby every four years. There is no reason to assume that the reason hunter-gatherer groups are smaller than traditional agricultural groups is that their death rates are higher. (Though that might be the case, it is a hypothesis that has to be tested in each group.) They may be using various methods to reduce birth rates to keep group size manageable. This isn’t necessarily a sign of doing things wrong. Even with a lower growth rate, human hunter/gatherer societies managed to cover most of the planet.

    I don’t think it’s necessary to assume that everything about hunter-gather societies was perfect to recognize that it drove most of our evolution, and that significant deviations from the lifestyle may need to be compensated for – for instance, through technology. For instance, hunter-gatherers tended to get more exercise than cube-farm dwellers. The cube-farm dwellers suffer health effects from lack of exercise, so they use their agriculture-and-fossil-fuel-enabled technology to build themselves gyms and take sulfonylurea drugs.

    Or, hunter-gatherers moved around and didn’t have to worry much about sewage. Agriculture made cities possible and urbanites spent thousands of years suffering from life in various quantities of s*** before flush toilets and rotavirus vaccine were invented. In the meantime, life in crowded medieval and industrial cities could be quite disgusting and unsanitary, killing babies and otherwise-healthy young people. Other animals, such as ants, for instance, can live in large communities without having the same s***-related problems that humans do. Ants evolved to live in large, stationary communities. Humans did not. That doesn’t mean I’m romanticising life as an ant.

    While it’s theoretically possible for a particular human community to be hunter-gatherers while having access to modern medicine, modern medicine is dependent on agriculture and fuel. So that will always be a non-option for humans generally. Either we have agriculture and modern medicine and technology; agriculture without modern medicine and technology; or hunting/gathering without modern medicine and technology.

    The potato famine is not something that was caused by poor agricultural practices. It was caused by extremely successful agriculture that supported a large (but impoverished) population that could not be supported by anything else. In the absence of potatoes, the Irish either had to leave (like good hunter-gatherers) or use capital (which they didn’t have but the English did) to import food.

    We’re going to be facing that again in the coming decades. Fertilizer and pesticides are going to become increasingly expensive and our huge agriculture-supported human population is going to be scrambling.

  57. Sid Offit says:

    Amy says:

    The difference between an average lifespan of 48 and one of 77.7 can be accounted for by modern medicine

    Everybody else says:

    Fertility and Mortality in the United States
    Michael Haines, Colgate University

    http://eh.net/encyclopedia/article/haines.demography

    The mortality decline since the late nineteenth century seems to have been the result particularly of improvements in public health and sanitation, especially better water supplies and sewage disposal. The improving diet, clothing, and shelter of the American population over the period since about 1870 also played a role. Specific medical interventions beyond more general environmental public health measures were not statistically important until well into the twentieth century

    ——————————————————————–

    https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/936/WP90-07_Childhood_Mortality.pdf

    The two extreme explanations of child mortality decline are on the one hand that the improvements are due to medical science and on the other that they are due to general improvements in economic and social conditions

    The first view, giving preeminence to medical advances, was the conventional wisdom until the 1950s, but has, since then, been largely discredited. As has been seen in the previous section, child mortality fell from a number of diseases (e.g., tuberculosis, pneumonia) in the early part of the 20th century for which there was no effective therapy or immunization

  58. “I would argue that a larger population with a lower life expectancy is indicative of worse health”

    Where is your evidence that this is what happened during the transition to agriculture? I can’t imagine how a pre-technological society could grow substantially in population without an increase in lifespan. Are you claiming that hunter-gather societies contained small numbers of individuals who lived to old age but had only a few children, all of whom survived to adulthood?

    “Because the archaeological record is replete with similar stories, as are historical accounts”

    Really? Name 5.

    “Children are helpless for the first decade of life, so the survival of genes is dependent on there being a large support network to ensure the survival of children, even if their parents die”

    Where’s the evidence that parental longevity leads to increased child survival? How does a support network prevent perinatal death, infectious disease and starvation in time of famine?

  59. Menopause: If I have a baby every four years until I’m 45 and then I die, who is going to look after my younger children and raise them until they’re sixteen? Menopause makes most sense if you assume that it makes at least a small core of women not tied down with infant care available to guide and support a group of younger mothers. My impression is that non-reproductive grandmothers are a prominent feature of the hunter-gatherer societies we know today. Otherwise, if you assume that women contribute to a healthy (=large?) society primarily or solely by the number of infants we generate, there would be no menopause. We would just keep popping them out until we keeled over.

  60. Anecdote: I attended a meeting yesterday about sensory integration in young children. Several attendees expressed disdain for modern civilization and technology because children no longer have to do the “hard sensory work” previously required for survival. In the peacefully idyllic past, evolution actively tuned children to be in harmony with their pre-civilization environment. Today’s technology and urbanism undermines this perfect balance and fails to honor our evolutionary history.

    There may be a germ of a point buried in there somewhere, but do we entirely discard 10K+ years of technology to return to nasty, brutish, and short? I live in a very cold climate, and have a great deal of concern about interruption in the supply chain to my local coffee roaster. It’s not as if I could grow my own beans here. Nasty and brutish indeed.

  61. Sid,

    Those quotes are meaningless One is from an encyclopedia and the other is someone’s opinion.

    Data, Sid, we need data!

  62. Sid Offit says:

    Amy

    No, no, no, that’s not how you support a claim with scientific evidence. You need to quote the relevant passages, discuss the limitations of the study or report, and compare it to the larger body of scientific evidence on the topic.
    Copy and pasting a link, which might impress lay people, carries no weight here.

    ———————

    Let’s simplify things. Show me a infectious disease that you believe would still be an important cause of infant/childhood mortality were it not for modern medicine and I’ll demonstrate you how you’re incorrect

  63. Sid Offit says:

    …and I’ll give you lots of data

  64. “Menopause makes most sense if you assume that it makes at least a small core of women not tied down with infant care available to guide and support a group of younger mothers”

    Actually, there is another explanation that makes more sense. Ova degrade in quality over the course of a woman’s life making the risk of giving birth to a child with a severe genetic defect (like Down’s Syndrome) increasingly common, particularly over age 40. Since children with genetic defects tend to die very early, and since childbearing is associated with a high risk of death, it makes biologic sense for ovulation to wind down when the quality of ova diminishes.

  65. “Show me a infectious disease that you believe would still be an important cause of infant/childhood mortality were it not for modern medicine and I’ll demonstrate you how you’re incorrect”

    Smallpox.

  66. lillym says:

    @ Allison – Menopause: If I have a baby every four years until I’m 45 and then I die, who is going to look after my younger children and raise them until they’re sixteen?

    I’d assume that there would be remarriage and the stepmothers would take care of the younger children as well as any children she had. I’m also assuming that the father would marry a younger woman. Or the children could be sent to live with relatives who could afford to take care of them.

  67. showmedadata says:

    Amy, I’ve been a reader of SBM for half a year or so and enjoy your articles. I must say though, that you’ve taken quite a condescending and belittling tone with Sid as you demand citations for evidence..

    “No, no, no, that’s not how you support a claim with scientific evidence. You need to quote the relevant passages, discuss the limitations of the study or report, and compare it to the larger body of scientific evidence on the topic.
    Copy and pasting a link, which might impress lay people, carries no weight here”

    In addition to an air of arrogance, you entirely fail to present such evidence in your own article! Thus, you have a very interesting opinion piece, full of fun speculation and plausible inference, but no Level Ia evidence for which you press Sid.

    D. Joo, MD

  68. dang typos:

    “…you’d better make sure your not standing in a glass house when you do it.”

    Corrected: “…you’d better make sure you’re not standing in a glass house when you do it.”

  69. Karl: Stunted growth:

    It doesn’t take a lot of food restriction to stunt growth. Children have a lot of demands on the limited amount of food they can consume: physical maturation, exploring, learning, fighting disease, hunting and gathering. They grow with what’s left over. Assuming malnutrition in agricultural societies is what caused people to be shorter is entirely consistent with what we know about nutrition and changes in population heights today. For instance, all those 3rd-generation east-asian immigrants in North America who are so much taller than their grandparents. Or the Dutch army recruits who were conceived after the Hunger Winter of 1946 and who were significantly shorter than the recruits born earlier and later.

    Agriculture may lead to:
    — More sewage to deal with, more water-borne disease to fight off, therefore less energy available to fuel growth even with the same amount of food.
    — More children per mother, leading to earlier weaning of infants and more competition for food among children.
    — More dependence on local crops, so a boom-and-bust cycle of feast and famine.
    — More dependence on grain and less consumption of meat.

    Also:
    — More staying at home, better housing, cleared land and fewer (not more) predators.

    Even if agriculture can support more people, it wouldn’t be surprising if they were smaller, at least in some circumstances. (Pygmies are hunter-gatherers. They aren’t very big.)

    This is actually a testable hypothesis, so someone with anthropological savvy (not me) can probably go and look up the data. In populations with nutrition-related growth restriction, men and women are of similar height because there is not enough surplus food to fuel a complete male adolescent growth spurt. Back in my university days I had a professor who used to talk about that phenomenon being quite visible in Newfoundland, where sex differences in height in the older generation were less pronounced than in the younger generation.

    We also haven’t been talking about pastoralists, who are probably the healthiest of the preindustrial groups. They’re tall, mobile and have ready access to animal protein. They can accumulate capital, which offers protection against lean times.

  70. showmedadata:

    “no Level Ia evidence”

    Are there any empirical claims in the piece for which you would like to see scientific citations? I’d be happy to provide them.

  71. Calli Arcale says:

    Allison Cummins:

    Menopause: If I have a baby every four years until I’m 45 and then I die, who is going to look after my younger children and raise them until they’re sixteen?

    Your family. Humans are social animals, and even in hunter-gatherer groups, children are looked after by more than just their parents. But if you think survival is impossible if people die at 45, consider the fact that in societies without good access to medical care, the maternal death rate can be as high as 10%, so clearly there is a fairly significant risk that a child won’t just become motherless before 16, but may come into the world motherless. Yet our species survived. This is because traits do not survive only if they guarantee survival. They don’t have to be perfect; they just have to improve the odds.

    The “grandmother hypothesis” has been floated before to explain menopause, but while I find it plausible, I am not yet convinced. In any case, even if true, it doesn’t mean women usually made it past menopause (nor does it mean that men did). One potential complicator: men and women both care for the children, but although male fertility does decline with age, they don’t really have any equivalent to menopause. Why? Shouldn’t it be just as bad to father a child at 75 and guarantee the child will be fatherless at 16?

    There may be another reason why menopause developed. It’s long been known that parental age is associated with the rate of birth defects; as the parents get older, so goes the idea, their gamete-production-systems accumulate genetic defects, some of which will be fatal to the offspring. For a while, it was held that autism was associated with advanced maternal *and* paternal age, but interestingly, a newer study has largely exonerated the fathers; it’s advanced *maternal* age, not paternal, that is associated with an increase. It’s not yet certain that this is causal, but it has me wondering: is menopause adaptive from the perspective of reducing birth defects?

    (Mind you, the two explanations are not mutually exclusive.)

    I’ve rambled a bit here, but my point is that you can’t point to menopause as evidence that people were generally healthy five thousand years ago. I think it’s safe to say that people *were* generally as healthy then as they are today, as long as they didn’t have any serious accidents, get seriously ill, eat spoiled food, drink tainted water, get snakebit, die in childbirth, get in infection, be unfortunate enough to have a congenital defect, etc. Like most species, we cope with our premature death rate by having enough babies to make up the difference, but it’s probably fair to say our wild life expectancy was in the order of 70 years, barring illness or accident or famine. Our modern life expectancy *is* higher than that (reaching 80 is not considered extraordinary anymore — 90 is the new 80, you might say), but not 35 years higher.

  72. bluedevilRA says:

    I suspect people romanticize our H-G ancestors because they fancy the idea that if we had to return to those uncivilized times, then they would be the one’s who survive. People like to be counted among the strong. Civilization apparently makes us weak.

    I’m guilty too. That’s why I like a good zombie survival story. Everyone likes to imagine they would be the sole survivor during a zombie holocaust.

  73. lillym on motherless infants:

    I’d assume that there would be remarriage and the stepmothers would take care of the younger children as well as any children she had. I’m also assuming that the father would marry a younger woman. Or the children could be sent to live with relatives who could afford to take care of them.

    In fact, when life is hard, the new young wife is often not at all keen on looking after another woman’s children. Think of all the Evil Stepmother stories from preindustrial Europe. There seems to be an atavistic response that survives today. My sister was taken into care by the children’s aid because it was feared that her stepmother would kill her and her older sister. Sure, that’s unusual and extreme, but stepmothers are unreliable.

    When I lived in Africa, children who could not live with their mother (mother died, or mother remarried and new husband was not interested in supporting another man’s child) were sent to live with their maternal grandmother. If this wasn’t possible, they might be adopted by a childless aunt. Otherwise they would be sent to live with someone who needed a small child to fetch wood and carry water. This was definitely a last resort, though. In many cultures a motherless girl can be betrothed and sent to be raised by her future mother-in-law at any time.

  74. Zoe237 says:

    “But is mere numbers of people the only measure of health?”

    Dr. Tuteur:

    “Not the only measure, but one of the best. The unhealthy die prematurely. It’s difficult to be less healthy than when you are dead.”

    Hmm, sub-saharan Africa must be the healthiest in the world then!

    It would be nice to see one shred of evidence to prove Dr. Tuteur’s assertions, especially that modern agriculture is primarily responsible for an increase in life expectancy. Dr. Gorski and Alex Knapp are the only one who have provided any backup for his statements. Further, it’s rather odd that the claims in the blog are taken as true with no research evidence, but anybody who questions the conclusions must provide iron-clad data (although these commenters are rising to the challenge, even if it’s not reciprocated). There is tons of debate among historians and scientists about the role of agiculture in evolution and population growth and life expectancy, so there’s no shortage of evidence.

    I do agree with Dr. Tuteur that there is no evolutionary advantages to having people live past reproductive age.

    Alison, I also have read that hunter-gatherers cannot carry their children long distances, so they tend to have less of them (due to lactational ammenorhea, assuming). A transition to urban areas and close quarters made possible by agriculture most certainly INCREASED population at first, but lead to decreased life expectancy. All of Dr. Tuteur’s points apply to post neolithic societies.

    The diseases of hunter gatherer societies DON’T tend to be influenza, tuberculosis, smallpox, but things like chagas disease.

    There are some skeptic authors (like Michael Shermer) who like to see the EBM approach applied to areas such as history. Obviously there are no RCTs, so the subject of this blog post is different than the usual.

    I agree with whoever said that it’s ALSO dangerous to romanticize the present. Before modern sanitation, agriculture most likely lead to increased population, but decreased life expectancy.

  75. Amy on menopause:

    “Ova degrade in quality over the course of a woman’s life making the risk of giving birth to a child with a severe genetic defect (like Down’s Syndrome) increasingly common, particularly over age 40. Since children with genetic defects tend to die very early, and since childbearing is associated with a high risk of death, it makes biologic sense for ovulation to wind down when the quality of ova diminishes.”

    If a living mother has no value, it makes no difference whether her children are at higher risk of Down syndrome. It only makes sense to reduce childbearing to spare her life if her life has value to the population beyond the infants she can produce.

  76. Zoe237 says:

    Calli Arcale:

    “Like most species, we cope with our premature death rate by having enough babies to make up the difference, but it’s probably fair to say our wild life expectancy was in the order of 70 years, barring illness or accident or famine. Our modern life expectancy *is* higher than that (reaching 80 is not considered extraordinary anymore — 90 is the new 80, you might say), but not 35 years higher.”

    That was my impression as well. Is there a “ceiling” for human lifespan? Why do we die, evolutionarily speaking? I’ve seen lots of debate among scientists about theories of aging- fascinating stuff.

  77. showmedadata says:

    Amy,

    Since you offered:

    1. Your basic premise is that life expectancy has increased from 35 to 77 due to modern medicine and agricultural advances. Although I don’t doubt this, you give no evidence. Furthermore, there’s haziness in your assertion that “for most of human existence” the life expectancy was 35 years.. How far back does that go? How reliable are the indicators we use to determine that value?

    2. Regarding life ‘back then’, you state “It was hell”. Again, likely true because life has always been a battle of survival. Evidence? Presumably there were some pretty decent parts then as there are now.

    3. The most flagrant of your assertions, somewhat mitigated by Harriet’s comment with which you agreed:

    “All the existing scientific evidence shows that all of the myriad claims of alternative health are flat out false. None of it works, absolutely none of it”

    As this is a blanket, absolute statement, a single example to the contrary will suffice. Laser therapy for chronic neck pain (Ia Evidence).

    Chow RT, Johnson MI, Lopes-Martins RA, Bjordal JM. Efficacy of low-level laser therapy in the management of neck pain: a systematic review and meta-analysis of randomised placebo or active-treatment controlled trials. Lancet 2009;374(9705):1897-1908.

    Medicine and reality are not worlds of absolutes (at least to our current state of understanding). The more black-and-white the opinion, the more I slot it into the “fundamentalist” or “religious fervor” category.

  78. wales says:

    Amy said to Sid “Those quotes are meaningless. One is from an encyclopedia and the other is someone’s opinion.”

    1) Referring to the “encyclopedia” comment, which cites a paper by Michael Haines of Colgate University, here is a link to papers by Haines on this topic. http://www.nber.org/authors/michael_haines
    (the Economic History Association might quibble with their online encyclopedia being deemed “meaningless”).

    2) Amy dismisses the paper “The Decline of Childhood Mortality” by Kenneth Hill of the Johns Hopkins School of Public Health as “someone’s opinion”.

    Question: if Dr. Hill’s academic paper, which includes two pages of reference citations, is deemed “mere opinion” then how should we categorize Amy’s undocumented claims? Mere speculation?

    Dismissing legitimate academic papers as “meaningless” and “mere opinion” is beyond the pale. What is Amy smoking/imbibing?

    So far Sid’s citations are the most educational thing about this post.

  79. passionlessDrone says:

    Hi bluedevilRNA –

    Everyone likes to imagine they would be the sole survivor during a zombie holocaust.

    So true. Why is it, though, that a zombie holocaust is fun to imagine, but most other forms don’t romanticize so easily?

    And on a related note, what might the zombie apocalypse to do our average lifespan? Does your timeframe as a brain eating zombie count?

    - pD

  80. lillym says:

    In fact, when life is hard, the new young wife is often not at all keen on looking after another woman’s children. Think of all the Evil Stepmother stories from preindustrial Europe. There seems to be an atavistic response that survives today. My sister was taken into care by the children’s aid because it was feared that her stepmother would kill her and her older sister. Sure, that’s unusual and extreme, but stepmothers are unreliable.

    But for every extreme and rare case there are those situations where children were raised by their father’s second (or sometimes third) wives.

    I can point to my own famiy history where my grandmother has an older half-sister, my great grandfather’s first wife died, he remarried to my great grandmother and she raised her stepdaughter and her own children.

    There’s also a great-great-great (I think I’ve got that right) uncle who had 17 children by three different wives. His second and third wives were actually younger than the oldest children.

    Then there’s also the fact that at least one grandparent of mine and both parents were raised with their cousins when the cousins’ parents either died or were unable to afford to care for them. In one case a great aunt died of pnemounia when she went to care of her sister who was dying of breast cancer. As a result all of those children (I believe about eight) were sent to live with various relatives, I don’t think any of the siblings ever lived together after that.

    This doesnt’ cover what happens when a father dies, in the case of one of my grandfathers when his father died his older sister married at the age of 14 and he and his younger sister were sent to “schools” because their mother had no money and no desire to try and care for them.

  81. Plonit says:

    More children per mother, leading to earlier weaning of infants and more competition for food among children.

    ++++++++++++

    Surely it’s the other way round? Earlier weaning of infants leads to more children per mother, all other things being equal.

  82. Amy on parents:

    “Where’s the evidence that parental longevity leads to increased child survival? How does a support network prevent perinatal death, infectious disease and starvation in time of famine?”

    Ooh, I really wish I could go to the McGill Medical library right now and look it up. (Which I have in the past.)

    In times of war and famine, children who are with their mothers are less vulnerable to malnutrition than are children who are with aunts, grandmothers, fathers, stepmothers or some random stranger. Mothers will go further to save a baby’s life than anyone else will.

    You can challenge me and I will be helpless before you, but this was part of my senior thesis. (Back in the eighties. There might be better work done now, which I would be glad to hear of.)

    From a slightly different angle: One sociological study of an agricultural village looked at all kinds of variables upside down and sideways — family size, father’s family size, mother’s family size, size of land available to family, distribution of land, quality of land — to find variables that would identify children at risk of malnutrition. In that village the only variable they could find was whether the mother had a cash income or not. If she had income she could buy snacks for her children and they would eat twice a day. If a mother didn’t have her own income, her children breakfasted on leftovers from supper — and that was it until they were old enough to stay up and eat supper with the grownups and get two meals a day. Agriculture is a lot of work, and food preparation is a lot of work, and there just isn’t the availability to provide children with food all through the day.

  83. Alison Cummins,

    I never maid any claim that food restriction does not result in stunted growth.

    In fact, I accepted the statement, “All else being equal, stunted growth is typically symptomatic of malnourishment.” as fact for the sake of argument since its factualness is not relevant to my point.

    My point was that Alex Knapp provided no support for the implied claim that reduced average height in the population of the scenario he presented was a result of stunted growth in the same thread in which he criticized Amy for not using citation to peer-reviewed research and analysis.

  84. Plonit says:

    With regard to diabetes, this world map makes interesting viewing

    http://www.worldmapper.org/display.php?selected=239

  85. Plonit on chickens and eggs:

    Surely it’s the other way round? Earlier weaning of infants leads to more children per mother, all other things being equal.

    One of the means a society can use to space births is a taboo against sex for lactating women which may be a two to four year period. In agricultural societies the taboo is typically shorter, less stringent, and may even be absent.

    Hunter-gatherer children don’t eat porrige, so they often can’t be weaned as young as agricultural children. Not weaning them delays mothers’ return to ovulation, absolutely. (However, we all know examples of the imperfection of this method!) If everyone knows they *must* not be weaned then the extended lactation period will be actively protected. (Even to the extreme of infanticide of a child born before the older child is ready to be weaned.)

  86. lillym on stepmothers:

    “But for every extreme and rare case there are those situations where children were raised by their father’s second (or sometimes third) wives.”

    Yes, and thank you for giving me the chance to agree with you!

  87. Calli Arcale says:

    Heh — I was menstruating two months after childbirth, both times, and I breastfed both my kids for over a year. It definitely is not reliable as a form of birth control.

    There is no reason to kill a child because a new child has been born while the first is still nursing; women can generally support two babies, milk-wise, and by then the older child is not exclusively drinking breastmilk. (If they did, they’d be malnourished; you really do need to start solids prior to age 2. Even the Muslims, who as an article of religious doctrine, are expected to nurse for two years, will introduce solids by six months. There is, after all, nothing saying it has to be the only source of nutrition.) I am doubtful that this happened very often even in ancient hunter-gatherer societies, especially given the paleontological evidence even in Homo erectus of taking care of seriously disabled tribe/clan members, and, more notably, the fact that it isn’t common in modern hunter-gatherer societies (what few still exist).

  88. Sid Offit says:

    Amy, you lack imagination.

    Let’s start with this:

    Infant and child mortality in the past By Alain Bideau, Bertrand Desjardins, Héctor Pérez Brignoli P31 (Google Books)

    …one must remember that smallpox had begun to diminish before vaccination. In Sweden smallpox mortality declined by close to half between 1770 and 1800.

    …in England the disease was in decline before the end of the century, as was the case in Geneva.

    —————–

    For actual data see Welch and Miller homage to vaccines, Acute contagious diseases

    http://books.google.com/books?id=fOc0TmQsPRkC&printsec=frontcover&dq=acute+contagious+diseases&cd=1#v=onepage&q=&f=false

    P109 England – falling mortality and rising population

    P 106, 111 Sweden – declining mortality

    —————–

    Besides for smallpox to live up to its reputation as the speckled monster, we’d need to return the squalorous conditions plaguing the people of the 17 and 1800s.

    As to temporal declines occurring after vaccination remember correlation does not equal causation

    Finally this is not to say vaccination, when practiced properly with actual vaccine, did not work or have an impact, simply that, as a major cause of mortality, smallpox was on its way out vaccine or not

  89. Sid Offit says:

    @Wales

    To listen to Amy you’d think this guy was Cliff Clavin spouting off at Cheers

    http://faculty.jhsph.edu/default.cfm?faculty_id=310

  90. Sid Offit:

    “For actual data see Welch and Miller homage to vaccines, Acute contagious diseases”

    No, YOU need to present the data and make the arguments. It is not enough to cite papers and books that you think make your point.

    Indeed, I would venture to guess that you keep throwing out citations because constructing an argument to support your claim is literally impossible.

  91. bluedevilRA says:

    Oh no, Sid, don’t do the “well the diseases were on their way and vaccines had little effect” gambit. This is awful Bill Maher garbage. Vaccines didn’t eradicate polio. Polio eradicated itself!

    Modern medicine didn’t get rid of diseases. They all just magically disappeared! The woo alarm in my head is ringing so loud I can barely hear myself think.

  92. Sid Offit says:

    I know this is just from a book but I couldn’t resist

    The Burdens of Disease
    By J. N. Hays P 279

    “Government compulsion did not…mean effective administration, and the rapid elimination of smallpox certainly did not result.”

    “National administration of a vaccine faced daunting practical problems in the 19th century. For much of the period adequate supplies of the vaccine could not be relied on, and their quality varied widely.”

    “Even after the serious epidemics of the early 1870s quality and quantity could not be assumed.”

    ——————-

    bluedevilRA

    I don’t want to get into polio, so for now I’ll say you’re right. If however you have another infectious disease eliminated by modern medicine I’d love to hear about it.

    Wooo hoooo!

  93. thehandsomecamel on pre-industrial life expectancy:
    “Once you made it to adulthood, life expectancy was basically the same for them as it is for us — most people lived to their seventies, which is why the Bible, for example, gives the average life expectancy (in ancient Israel) as “threescore and ten,” or “if they be strong, fourscore.” ”

    Israelites were pastoralists. Very clean, very well-nourished. I’m not surprised they thought 70 was a normal lifespan.

    David Gorski on pre-industrial life expectancy:
    “Only about 1/3 of people who made it to their 20s made it to age 60, and many fewer still to age 70 or 80, about 12-15% and 2-3% respectively. (I’m guesstimating from looking at a graph in the book.)”

    This is seventeenth-century London, a filthy place! If 12% of adult Londoners were able to survive to 70, I’m impressed. Really.

    David Gorski on pre-industrial life expectancy:
    “In all fairness, I note that life expectancy was significantly higher in the countryside, at least as far as the data we have suggest.”

    Right, so outside of urban areas, which have their own urban ills, people did much better. And most people did *not* live in cities in the 16th and 17th centuries.

    These are three very different modes of life, none of which are hunter-gatherer. The past is a big place.

    Amy Tuteur on *all* modes of pre-industrial life:
    “Far from being a paradise, it was hell.”

    Maybe, maybe not. For some people, clearly yes. For others, clearly no. Kind of like living in a modern industrial city is hell for some people (life expectancy of 57 for DC African-American men) and very nice for some people, thank you very much (life expectancy of 92 for affluent Asian-Americans).

    If you want to talk about what is good or bad about something, you need to be able to clearly define what the something is. Once you do that, you’ll probably find both upsides and downsides. (17th century London? Sounds awful to me, but people moved there because they liked it. At least some people apparently thought the risk of disease was worth it.)

  94. Plonit on infanticide:
    “There is no reason to kill a child because a new child has been born while the first is still nursing; women can generally support two babies, milk-wise, and by then the older child is not exclusively drinking breastmilk. … I am doubtful that this happened very often even in ancient hunter-gatherer societies.”

    You’re right that it probably didn’t happen very often. It depends on the alternatives to breastmilk.

    Agriculturalists have access to grain. Grains supply approximately 2-4% of their calories as protein and 1-4% of calories as fat. Legumes are even higher in fat and protein.

    Agriculturalists often have access to milk; pastoralists definitely do.

    Hunters and gatherers don’t eat much grain. They eat leaves, roots, fruits, tubers, nuts and meat. If you don’t have nuts where you live, the plant material available for your baby is low-protein and low caloric density. Bananas are the highest-protein fruit at about 2% of calories. With a little supplementation, an adult can live on bananas. A baby can’t. A baby with this range of plant food choices needs substantial meat or breastfeeding for the first 30 months, otherwise they are at high risk of kwashiorkor.

    In a traditional lifestyle, some people really do face horrible choices. In these circumstances the taboo against sex with a lactating woman is very strong.

  95. Plonit says:

    Not me! Calli Arcale said that….

  96. Sorry Plonit!

    Calli, consider yourself cited.

  97. Point of clarification (sorry if I missed this earlier)

    Lifespan is the maximum age an individual may live
    Life expectancy is the average age a population lives.

    Amy meant “life expectancy” in the article – not lifespan. These two terms have then been used interchangeably in the comments.

    So – human lifespan has actually not changed much. But life expectancy has increased – for every age group. If you are 40 now your life expectancy is greater than if you were 40 in 1800. This is not explained by decreased infant mortality.

    But it is true that decreasing infant mortality has had a disproportionate effect on life expectancy, since saving one child may add 70-80 years to their life.

    However, as someone pointed out, do you know anyone who is literally alive due to modern medicine?

    Also – if you look at individual diseases – cancer survival is increasing, heart attack survival is increasing, stroke survival is increasing, etc.

  98. “Also – if you look at individual diseases – cancer survival is increasing, heart attack survival is increasing, stroke survival is increasing, etc.”

    But Steven, the naturalists insist those diseases didn’t exist in olden times; they are all a result of our modern, unnatural lifestyles. They will probably counter that, yes, today we are getting better at finding ways of living longer with our unnatural, unhealthy lifestyles.

    Apparently there are people who believe that back in the day, ancient man lived a long, strong, and healthy life up to the minute he just dropped dead of old age one day in the middle of running around hunting and gathering nuts.

  99. ryanodine says:

    “Remember, evolutionary success is measured by number of living offspring, not by length of life. Natural selection does not select for health, it selects for reproductive outcomes.”

    Natural selection isn’t the only factor. Sexual selection would select for health.

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