Situation Normal, All Clueless
Irradiated by LabRat
Commenter Geodykt left a long but well worth it response to my last post, fleshing out the history of medicine, its practices, and the reason that bloodletting seemed like such a good idea beyond “variable reinforcement”, as well as pointing out one other common ailment that bloodletting would probably have given a positive immediate result for, if not a real treatment as we’d understand it- chronic hypertension.
One of the things he touches on that I wanted to expand upon is the idea that for a very long time in medicine and still to a frightening degree today, one of those gaps in medical knowledge that no one really thought about or thinks about much now is our idea of what “normal” is. One of the reasons he cites for why bloodletting seemed so harmless is that, for a long time, no one really knew how much blood an adult human is toting around- and believed it to be around twice as much as we actually do. Medicine focuses on pathology, not normality; almost all studies and research, then and now, focuses on what a human that is unhealthy in some way looks like. We also have an extreme distaste for cutting into the dead to examine them; medicine and anatomical study was the only justification, no culture that I’m aware of has ever treated autopsy with more affection than distaste, and the idea of dissecting the dead just so medical students can learn from them has always sat a little uneasily even if the doctors have mostly won that argument these days. It is much better now than it was then- for a long time, medical schools and pathologists had three sources of corpses: criminals, those too poor to pay for funeral arrangements, and those who died for unknown reasons that cry out for answers*.
One modern way in which this focus on the pathological plays out is studies linking particular genes to particular pathologies; I intend to go into this much more in a later post, but the relevant point to this one is that we much more often start from a point of pathology or undesirability- heart disease, particular types of cancers, criminal behavior- and try to find genes that lots of people who exhibit that pathology have, rather than asking how many people have that gene and are entirely unremarkable and normal. In my perfect world, the Human Genome Project’s purpose would be to sequence as many genomes as possible so that a complete picture of what “normal” can look like, much as the bone collections of physical anthropologists strove to do before people started to think that body-snatching was wrong even if it was from some foreign culture we didn’t think much of.
One particularly sad consequence of the lack of knowledge of what “normal” really looks like involved our spending a really alarming number of decades irradiating childrens’ throats, which led to just about as much thyroid cancer down the road as you imagined. It began with the corpses of the poor in medical schools.
At the close of the nineteenth century, a thing that was worrying doctors was the growing recognition of healthy infants simply up and dying as possibly having had some cause other than a dastardly parent smothering the child. We call it Sudden Infant Death Syndrome now and we still have no good ideas about what does it other than a vague idea we shouldn’t let infants sleep on their stomachs, but at the time pathologists were busily looking for a cause. They managed to find a difference between the tissues of the infant corpses they had who had died of SIDS, and those that had died and wound up in their autopsy bay for other reasons: the SIDS babies had significantly larger thymus glands, a structure in the neck that was at the time very poorly understood. The theory was: these infants with enlarged thymus glands stopped breathing in their sleep because that bloated thymus gland was compromising their airway. A new disease was born: status thymicolymphaticus. The treatment: shrink that thymus! The method: surgery at first, but it is really very difficult to cut down or remove a thymus gland in an infant; when “roentgen therapy” (irradiation) came on the scene, it was a godsend to children with status thymicolymphaticus, as the thymus could be shrunk with radiation. Much better than surgery.
We know several things now that we didn’t know then. One of those things is that the thymus is part of the lymphatic system, that its function is mostly to produce T cells, and that it’s normal for the thymus to be most active- and largest- in children, the younger the bigger. Newborn infants- the ones most vulnerable to SIDS- have the largest thymus relative to their body size of all, because it’s busy establishing their immune systems. We also have had Hans Selye‘s work and all that followed since then, which established that stress produces real and lasting physiological changes beyond just making us jittery and unhappy. One of those changes is that chronic stress shrinks lymphatic tissues- like the thymus gland.
The SIDS infants in the pathology bays were there specifically because they had died and no one knew why; they were a representative cross-section of infantkind, if anything biased toward infants from wealthier families because their deaths were more likely to be impossible to attribute to any other cause. The other infants were almost all from poor families who had died of the lethalities of poverty at the time- tuberculosis, chronic diarrheal diseases, malnutrition. In short, they had probably been born into stress and had most certainly died after a long period of stress that had the physiological toll that stress does and atrophied their lymphatic tissues before they died. The SIDS babies were possibly the only babies with normal thymuses the pathologists had seen.
“Status thymicolymphaticus” took its toll until the mid-thirties, when the last spate of genteel fighting in the medical journals settled down to the general consensus that it probably couldn’t be what was causing SIDS, though the concept of children having enlarged thymuses rather than normal ones lingered on for awhile longer. The last scholarly paper citing it as a real condition I could find through Google was dated 1959, and discussed the beginning of the fallout of thyroid cancers in individuals who had had their throats irradiated as children to treat it. There was no dramatic fanfare that medical science had done something horrible to children out of simple ignorance due to that lack of a “normal” baseline; it simply was concluded to be an outdated theory and then later concluded that it had probably had bad effects later on.
It won’t be the last time, either; simply due to the nature of medicine as a science, such things are probably inevitable. I don’t know what the next one will be, either, but I will say I am very curious to see in about thirty years what medicine thinks of encouraging people to eat as little fat as possible.
*And stolen corpses, of course, but these were again almost always the bodies of the poor.
December 21st, 2010 at 6:36 pm
Interesting.
I had an acquaintance (back when I was in grad school…he was an older member of the community that I got to know on a hunting trip) who had a PSA test taken, and it came back high.
The doctors attributed it to potential prostate problems…except that the gentleman said the doctors really needed a baseline and a spike to diagnose trouble.
That got me thinking about blood tests. (I think I’m two decades away from my first PSA test…but others come to mind.)
I assume that blood-sugar has a well-known normal range. But how is the normal established? With reference to people complaining of symptoms of diabetes, or with reference to a generic healthy sample?
What about cholesterol? How well-known is a healthy cholesterol level?
These things make me wonder.
December 22nd, 2010 at 7:06 am
…I am very curious to see in about thirty years what medicine thinks of encouraging people to eat as little fat as possible.
Throwing the paleos a bone?
I’m also fascinated to see where nutrition science goes. Right now, it seems to have a slightly higher vodoo/math ratio than the rest of medical science. That’s not a criticism of the scientists; there are about a trillion variables that you can’t ethically control. As with all science, it can take a long time for good, reliable conclusions to shake out.
December 22nd, 2010 at 8:57 am
I assume that blood-sugar has a well-known normal range. But how is the normal established? With reference to people complaining of symptoms of diabetes, or with reference to a generic healthy sample?
60 - 120 mg / dL, in fact.
Since blood sugar testing is significantly less invasive than measuring the whole blood volume of a person, that number was established based on a wide, wide sample population, as far as I’m aware.
I think there’s still significantly less solid conclusions about “healthy” levels of cholesterol, though.
December 22nd, 2010 at 1:10 pm
It seems certain to me that x decades from now (x approx. 5), when AIDS has joined smallpox in the dustbin of historical diseases, some of the phenomenally expensive and tremendously toxic drugs now used will be regarded with the thought, “What were those witchdoctors thinking?!?” With some justification and more not. The treatments for AIDS, and even the research for the cause of AIDS, was done under extreme time pressure. There were procedural shortcuts because we needed answers fast, and there are huge ethical questions about delaying treatment, ANY treatment, just for the purpose of finding out if it is effective. (Yes, that can be interpreted more than one way.)
December 22nd, 2010 at 1:27 pm
TSH level (used to measure thyroid function) is another one that doesn’t seem to have a good reference range. The symptoms of hypothyroidism are not well-quantifiable (feeling cold and tired, weight gain) and easy for doctors to attribute to laziness and whininess. Trying to get treatment for hypothyroid when you have raging symptoms but only a “borderline” TSH can range from maddening to impossible.
December 22nd, 2010 at 2:09 pm
Elmo- no bone-throwing. I think the paleo people on the whole have got the right end of the stick, I just think many in the community take the whole “if it was like it was for cavemen, it must be good for us” thing waaaaaaay too far.
The more I read about early human evolution, the more I think the story of our particular brand of hominid is not just the story of meat, but the story of fat. Especially for European neanderthals and cro-magnons, the guiding star of life- the difference between thriving and starving- must have been fat. While I agree with problems of abundance as problems, I find the idea that we must be most healthy when subsisting almost entirely on what was distinctly substandard fare for most of our evolution to be completely insane.
PSA, cholesterol, TSH… none of those I’d put in a category where I think the picture of “normal” has been accurately determined.
December 22nd, 2010 at 4:40 pm
For some reason that I can’t put my finger on this reminds me of the whole asthma situation. We know it’s an autoimmune overreaction, but we don’t know what the combination is that sets it up. I’m convinced (unreasonably, of course) that a key component is an environment that is too sterile, and I think that one of the other keys is an acute irritant. For an uncle of mine, I think it was 50’s Air Force cleanliness living on base, combined with the jet fuel my grandfather came home with on his uniform.
I really worry when I see these “boil everything and carry a bottle of hand sanitizer all the time that I liberally douse my spawn with every time they get near anything” parents. I think that in 50 years, when we do understand it, we’ll see it as child abuse to keep a kid that sanitary.
December 22nd, 2010 at 6:42 pm
I just think many in the community take the whole “if it was like it was for cavemen, it must be good for us” thing waaaaaaay too far.
Paleolithic diet, ok. Paleolithic sanitary practices? Not so much. Let’s please recall that “35” was old age for cavemen. I think soap has adequately proven itself.
(Though yes, Phelps, I agree with your position, too.)
Of course, it’s also important to remember how much exercise the paleos got just trying to survive. Unless you run to work and run around at work and run home from work, you’re probably well served to reduce your portion size.
I suspect most cavemen (if you’re not fit, you’re dead!) would give many current day Olympians a run for their money.
December 25th, 2010 at 5:11 pm
Perlhaqr,
While (as far as I recall), 35 was indeed “old age” (or at least “late middle age”, but almost any animal “living in the wild” tends to have a shorter, more brutish, life, than a pampered domesticated animal, like say, a movie producer in Los Angeles — and sometimes, it’s the mileage more than the years), it is easy to take the idea of “average” lifespan (or even “median age at death”), and confuse it with a mathematical relationship to current average or median ages at death.
Remember, childhood deaths due to disease or accident are meaningless in terms of actuarial lifespan in adulthood. They drag down both the average and median lifespans, but don’t mean people are old at 35. If a hair over 50% of the livebirth population of a hypotheitical tribe dies before age 2, everyone else could have a death age distribution about the same as the late 20th Century United Kingdom, and you would end up with a median age at death or average lifespan of about 35 years. . . but a 50 year old Welsh coal miner would probably be in worse shape than one of our 50 year old tribesman. (Better nutrition, maybe, and certainly better health care available — but WAY worse environmental conditions, and likely equal physical hazards.)
Once a paleolithic hunter-gatherer passes the childhood crisis years, their actuarial life expectancy goes up quickly. Once they pass the danger zones of childbirthing years and active hunting party participation, their actuarial life expectancy shoots up again.
While RARE (because their age cohorts were dramatically thinned by childhood diseases and accidents, theagain by physical traumas involved in trying to kill horned herd herbivores or child bearing), paleolithic oldsters have about the same remaining lifespan as any pre-antibiotic Western poverty population. Physical conditions not too dissimilar to what you would see in generational poverty populations of Appalachia or urban ghettoes in America today. Certainly not really any different than 18th or the first half of the 19th Century America.
Keep in mind that one of the significant improvements in quality of life that increases the vigor of modern Western populations is increased dental care to preserve teeth, and adequate prosthesis to supplement lost or broken teeth. Ancient Romans, middle ages Moslems, and Rennaisance and Age of Reason Europeans all had the capacity to do root scaling, fill cavities, do root canals, etc, knew that regular preventative treatments like root scaling were beneficial, etc — their “theories” of what was going on sucked, but the physical skills and practical applications were pretty well understood. Unfortunately, it hurt a LOT, so the demand for those skills was limited to wealthy vanity practice.
Modern dentistry has the advantages of imagery, antibiotics, amalgrams and synthetics, anesthesia, electrically powered tools and handy lights. However, a Special Forces medic forced to do emergency dentistry in the field uses pretty much the same physical techniques as his toga’ed or whitened wig wearing predecessors, with pain pills and penicillin to assist.
In short, we DID NOT magically select for a doubled lifespan with the invention of antibiotics and antiseptic surgery. We just keep enough casualties alive long enough to radically alter the statistics.
December 26th, 2010 at 1:00 am
As far as cavemen versus Olympic atheletes, it depends.
A caveman is going to be a generalist, with high mid-range endurance. Think, “1970’s Chevy S-10 pickup”. He’ll be pretty good at almost any physical challenge he is reasonably familiar with.
The Olympian will be a highly maximized specialist. Think “Formula 1 car”, “Aussie SAS LWB Land Rover”, etc. Try to play his game, and he’ll smoke you like Woody Harrelson at a 4/20 rally. In any other field, the athlete may or may not be able to hold his own, depending on how much he can leverage his specialization.
Two events Og the Caveman rules at are the ever popular, “Eat until painful distension, fast for a week, and then catch Mr. Bunny with a rock,” and the classic literal gut check, “I can swallow it, but can I keep it down?”