BR_The Body Bill bryson Flashcards
Chapter 1: The biggest component in any human, filling 61 percent of available space, is oxygen. It may seem a touch counterintuitive that we are almost two-thirds composed of an odorless gas.
Of the fifty-nine elements found within us, twenty-four are traditionally known as essential elements, because we really cannot do without them.
Well, you blink fourteen thousand times a day—so much that your eyes are shut for twenty-three minutes of every waking day.
In the second or so since you started this sentence, your body has made a million red blood cells. They are already speeding around you, coursing through your veins, keeping you alive. Each of those red blood cells will rattle around you about 150,000 times.
Unpacked, you are positively enormous. Your lungs, smoothed out, would cover a tennis court, and the airways within them would stretch nearly from coast to coast. The length of all your blood vessels would take you two and a half times around Earth. The most remarkable part of all is your DNA (or deoxyribonucleic acid). You have a meter of it packed into every cell, and so many cells that if you formed all the DNA in your body into a single strand, it would stretch ten billion miles, to beyond Pluto. Think of it: there is enough of you to leave the solar system. You are in the most literal sense cosmic.
The heart of the cell is the nucleus. It contains the cell’s DNA—three feet of it, as we have already noted, scrunched into a space that we may reasonably call infinitesimal. The reason so much DNA can fit into a cell nucleus is that it is exquisitely thin. You would need twenty billion strands of DNA laid side by side to make the width of the finest human hair. Every cell in your body (strictly speaking, every cell with a nucleus) holds two copies of your DNA. That’s why you have enough to stretch to Pluto and beyond.
What is perhaps most remarkable is that nothing is in charge.
Your DNA is simply an instruction manual for making you. A length of DNA is divided into segments called chromosomes and shorter individual units called genes. The sum of all your genes is the genome. DNA is extremely stable. It can last for tens of thousands of years.
You will die and fade away, but your genes will go on and on so long as you and your descendants continue to produce offspring. And it is surely astounding to reflect that not once in the three billion years since life began has your personal line of descent been broken. For you to be here now, every one of your ancestors had to successfully pass on its genetic material to a new generation before being snuffed out or otherwise sidetracked from the procreative process. That’s quite a chain of success.
Nobody knows how many types of proteins there are within us, but estimates range from a few hundred thousand to a million or more.
Five out of every six smokers won’t get lung cancer. Most of the people who are prime candidates for heart attacks don’t get heart attacks. Every day, it has been estimated, between one and five of your cells turn cancerous, and your immune system captures and kills them. Think of that. A couple of dozen times a week, well over a thousand times a year, you get the most dreaded disease of our age, and each time your body saves you.
Of course, very occasionally a cancer develops into something more serious and possibly kills you, but overall cancers are rare: most cells in the body replicate billions and billions of times without going wrong. Cancer may be a common cause of death, but it is not a common event in life. Our bodies are a universe of 37.2 trillion cells operating in more or less perfect concert more or less all the time.*2 An ache, a twinge of indigestion, the odd bruise or pimple, are about all that in the normal course of things announces our imperfectability. There are thousands of things that can kill us—slightly more than eight thousand, according to the International Statistical Classification of Diseases and Related Health Problems compiled by the World Health Organization—and we escape every one of them but one. For most of us, that’s not a bad deal.
Don’t forget that your genes come from ancestors who most of the time weren’t even human. Some of them were fish.
Skin flakes are properly called squamae (meaning “scales”). We each trail behind us about a pound of dust every year. If you burn the contents of a vacuum cleaner bag, the predominant odor is that unmistakable scorched smell that we associate with burning hair. That’s because skin and hair are made largely of the same stuff: keratin.
Sometimes the pores become blocked with little plugs of dead skin and dried sebum in what is known as a blackhead.
He peeled back a sliver of skin about a millimeter thick from the arm of a cadaver. It was so thin as to be translucent. “That,” he said, “is where all your skin color is. That’s all that race is—a sliver of epidermis.”
We can get it in two ways—from the foods we eat or through sunlight. The problem is that too much UV exposure damages DNA in our cells and can cause skin cancer. Getting the right amount is a tricky balance. Humans have addressed the challenge by evolving a range of skin tones to suit sunshine intensity at different latitudes. The red of sunburn is because the tiny blood vessels in the affected areas become engorged with blood, making the skin hot to the touch.
In regions like northern Europe and Canada, it isn’t possible in the winter months to extract enough vitamin D from weakened sunlight to maintain health no matter how pale one’s skin, so vitamin D must be consumed as food, and hardly anyone gets enough—and not surprisingly. To meet dietary requirements from food alone, you would have to eat fifteen eggs or six pounds of swiss cheese every day, or, more plausibly if not more palatably, swallow half a tablespoon of cod liver oil. In America, milk is helpfully supplemented with vitamin D, but that still provides only a third of daily adult requirements. In consequence, some 50 percent of people globally are estimated to be vitamin D deficient for at least part of the year. In northern climes, it may be as much as 90 percent.
If you have blue or green eyes, it’s not because you have more of those colors in your irises than other people but because you simply have less of other colors. It is the lesser of other pigments that leaves the eyes looking blue or green.
A hair in your armpit is likely to last about six months, a leg hair for two months. Removing hair, whether through cutting, shaving, or waxing, has no effect on what happens at the root. We each grow about twenty-five feet of hair in a lifetime, but because all hair falls out at some point, no single strand can ever get longer than about three feet.
“The loss of most of our body hair and the gain of the ability to dissipate excess body heat through eccrine sweating helped to make possible the dramatic enlargement of our most temperature-sensitive organ, the brain.” That, she says, is how sweat helped to make you brainy.
Unless the loss is halted or replenished, the victim will begin to suffer headaches and lethargy after losing just three to five quarts of fluid. After six or seven quarts of unrestored loss, mental impairment starts to become likely. (That is when dehydrated hikers leave a trail and wander into the wilderness.)
You have about 100,000 microbes per square centimeter of your skin, and they are not easily eradicated. According to one study, the number of bacteria on you actually rises after a bath or shower because they are flushed out from nooks and crannies. But even when you try scrupulously to sanitize yourself, it isn’t easy. To make one’s hands safely clean after a medical examination requires thorough washing with soap and water for at least a full minute.
Had their belly buttons swabbed to see what was lurking there microbially. The study found 2,368 species of bacteria, 1,458 of which were unknown to science.
The problem with antibacterial soaps is that they kill good bacteria on your skin as well as bad. The same is true of hand sanitizers. In 2016, the Food and Drug Administration banned nineteen ingredients commonly used in antibacterial soaps on the grounds that manufacturers had not proved them to be safe over the long term.
Microbes are not the only inhabitants of your skin. Right now, grazing in the divots on your head (and elsewhere on your oily surface, but above all on your head) are tiny mites called Demodex folliculorum. They are generally harmless, thank goodness, as well as invisible. They have lived with us for so long that according to one study their DNA can be used to track the migrations of our ancestors from hundreds of thousands of years ago.
the most extraordinary case of unappeasable suffering concerned a patient known as M., a Massachusetts woman in her late thirties who developed an irresistible itch on her upper forehead following a bout of shingles. The itch became so maddening that she rubbed the skin completely away over a patch of scalp about an inch and a half in diameter. Medications didn’t help. She rubbed the spot especially furiously while asleep—so much so that one morning she awoke to find a trickle of cerebrospinal fluid running down her face. She had scratched through the skull bone and into her own brain. Today, more than a dozen years later, she is reportedly able to manage the scratch without doing severe damage to herself, but the itch has never gone away. What is most puzzling is that she has destroyed virtually all the nerve fibers in that patch of skin, yet the maddening itch remains.
About 60 percent of men are “substantially bald” by the age of fifty. One man in five achieves that condition by thirty. Little is understood about the process, but what is known is that a hormone called dihydrotestosterone tends to go slightly haywire as we age, directing hair follicles on the head to shut down and more reserved ones in the nostrils and ears to spring to dismaying life.
Eighty percent of the air you breathe is nitrogen. It is the most abundant element in the atmosphere and it is vital to our existence, but it doesn’t interact with other elements. When you take a breath, the nitrogen in the air goes into your lungs and straight back out again, like an absentminded shopper who has wandered into the wrong store. For nitrogen to be useful to us, it must be converted into more sociable forms, like ammonia, and it is bacteria that do that job for us. Without their help, we would die. Indeed, we could never have existed.
They provide you with about 10 percent of your calories by breaking down foods that you couldn’t otherwise make use of, and in the process extract beneficial nutriments like vitamins B2 and B12 and folic acid. Humans produce twenty digestive enzymes, which is a pretty respectable number in the animal world, but bacteria produce ten thousand, or five hundred times as many, according to Christopher Gardner of Stanford University. “Our lives would be vastly less well nourished without them,” he says.
The average bacterium weighs about one-trillionth of the weight of a dollar bill and lives for no more than twenty minutes—but collectively they are formidable indeed. The genes you are born with are all you are ever going to have. You can’t buy or trade for better ones. But bacteria can swap genes among themselves.
E. coli can reproduce seventy-two times in a day, which means that in three days they can rack up as many new generations as we have managed in the whole of human history. A single parent bacterium could in theory produce a mass of offspring greater than the weight of Earth in less than two days. In three days, its progeny would exceed the mass of the observable universe. Clearly that could never happen, but they are with us already in numbers beyond imagining. If you put all Earth’s microbes in one heap and all the other animal life in another, the microbe heap would be twenty-five times greater than the animalone. Make no mistake. This is a planet of microbes. We are here at their pleasure. They don’t need us at all. We’d be dead in a day without them.
As you sit here now, you are likely to have something like 40,000 species of microbes calling you home—900 in your nostrils, 800 more on your inside cheeks, 1,300 next door on your gums, as many as 36,000 in your gastrointestinal tract,
(Thin people have more gut microbes than fat people; having hungry microbes may at least partly account for their thinness.) That is of course just the numbers of species. In terms of individual microbes, the number is beyond imagining, never mind counting: it’s in the trillions. Altogether your private load of microbes weighs roughly three pounds, about the same as your brain.
Each of us contains about thirty trillion human cells and between thirty and fifty trillion bacterial cells (depending on a lot of factors like health and diet), so the numbers are much closer to being equal—though it should also be noted that 85 percent of our own cells are red blood cells, which aren’t true cells at all, because they don’t have any of the usual machinery.
Looked at genetically, you have about twenty thousand genes of your own within you, but perhaps as many as twenty million bacterial genes, so from that perspective you are roughly 99 percent bacterial and not quite 1percent you.
Each of us contains about thirty trillion human cells and between thirty and fifty trillion bacterial cells (depending on a lot of factors like health and diet), so the numbers are much closer to being equal—though it should also be noted that 85 percent of our own cells are red blood cells, which aren’t true cells at all, because they don’t have any of the usual machinery.
Looked at genetically, you have about twenty thousand genes of your own within you, but perhaps as many as twenty million bacterial genes, so from that perspective you are roughly 99 percent bacterial and not quite 1percent you.
Passionate kissing alone, according to one study, results in the transfer of up to one billion bacteria from one mouth to another.
Of the million or so microbes that have been identified, just 1,415 are known to cause disease in humans—very few, all things considered. On the other hand, that is still a lot of ways to be unwell, and together those 1,415 tiny, mindless entities cause one-third of all the deaths on the planet.
You are not a person but a world!
The herpes virus has endured for hundreds of millions of years and infects all kinds of animals—even oysters. They are also terribly small—much smaller than bacteria and too small to be seen under conventional microscopes. If you blew one up to the size of a tennis ball, a human would be five hundred miles high. A bacterium on the same scale would be about the size of a beach ball.
Ocean viruses alone if laid end to end would stretch for ten million light-years, a distance essentially beyond imagining. Something else viruses do is bide their time. A most extraordinary example of that came in 2014 when a French team found a previously unknown virus, Pithovirus sibericum, in Siberia. Although it had been locked in permafrost for thirty thousand years, when injected into an amoeba, it sprang into action with the lustiness of youth. Luckily, P. sibericum proved not to infect humans, but who knows what else may be out there waiting to be uncovered? A rather more common manifestation of viral patience is seen in the varicella-zoster virus. This is the virus that gives you chicken pox when you are small, but then may sit inert in nerve cells for half a century or more before erupting in that horrid and painful indignity of old age known as shingles.
Colds unquestionably are more frequent in winter than in summer, but that may only be because we spend more time indoors then and are more exposed to others’ leakages and exhalations.
The average adult touches his face sixteen times an hour.
flu virus can survive on paper money for two and a half weeks if it is accompanied by a microdot of snot. Without snot, most cold viruses could survive on folding money for no more than a few hours.
The more we expose microbes to antibiotics, the more opportunity they have to develop resistance. What you are left with after a course of antibiotics, after all, are the most resistant microbes. By attacking a broad spectrum of bacteria, you stimulate lots of defensive action. At the same time, you inflict unnecessary collateral damage. Antibiotics are about as nuanced as a hand grenade. They wipe out good microbes as well as bad. Increasing evidence shows that some of the good ones may never recover, to our permanent cost.
“The day is fast approaching when the bacteria inside us may not be resistant to two-thirds of the antibiotics we hit them with, but to all of them. Then we really are in trouble.”
“From the 1950s through the 1990s,” he says, “roughly three antibiotics were introduced into the U.S. every year. Today it’s roughly one new antibiotic every other year. The rate of antibiotic withdrawals—because they don’t work anymore or have become obsolete—is twice the rate of new introductions. The obvious consequence of this is that the arsenal of drugs we have to treat bacterial infections has been going down. There is no sign of it stopping.”
in the United States 80 percent of antibiotics are fed to farm animals, mostly to fatten them.
In 1945, the year that Alexander Fleming won the Nobel Prize, a typical case of pneumococcal pneumonia could be knocked out with forty thousand units of penicillin. Today, because of increased resistance, it can take more than twenty million units per day for many days to achieve the same result. On some diseases, penicillin now has no effect at all. In consequence, the death rate for infectious diseases has been climbing and is back to the level of about forty years ago.
pharmaceutical industry has retreated from trying to create new antibiotics. “It’s just too expensive for them,” Kinch says. “In the 1950s, for the equivalent of a billion dollars in today’s money, you could develop about ninety drugs. Today, for the same money, you can develop on average just one-third of a drug. Pharmaceutical patents last only for twenty years, but that includes the period of clinical trials. Manufacturers usually have just five years of exclusive patent protection.” In consequence, all but two of the eighteen largest pharmaceutical companies in the world have given up the search for new antibiotics. People take antibiotics for only a week or two. Much better to focus on drugs like statins or antidepressants that people can take more or less indefinitely. “No sane company will develop the next antibiotic,”
Or as a doctor put it to me, “We are looking at a possibility where we can’t do hip replacements or other routine procedures because the risk of infection is too high.” The day when people die once again from the scratch of a rose thorn may not be far away.
The great paradox of the brain is that everything you know about the world is provided to you by an organ that has itself never seen that world. The brain exists in silence and darkness, like a dungeoned prisoner. It has no pain receptors, literally no feelings. It has never felt warm sunshine or a soft breeze. To your brain, the world is just a stream of electrical pulses, like taps of Morse code. And out of this bare and neutral information it creates for you—quite literally creates—a vibrant, three-dimensional, sensually engaging universe. Your brain is you. Everything else is just plumbing and scaffolding.
A morsel of cortex one cubic millimeter in size—about the size of a grain of sand—could hold two thousand terabytes of information, enough to store all the movies ever made, trailers included, or about 1.2 billion copies of this book.
The brain is often depicted as a hungry organ. It makes up just 2percent of our body weight but uses 20 percent of our energy.
The most efficient brains, he found, were those that could solve a task quickly and then go into a kind of standby mode.
The tiny space between nerve cell endings is called a synapse. Each neuron connects with thousands of other neurons, giving trillions and trillions of connections—as many connections “in a single cubic centimeter of brain tissue as there are stars in the Milky Way,”
Each hemisphere of the cerebrum is further divided into four lobes: frontal, parietal, occipital, and temporal—each broadly specializing in certain functions.
The frontal lobe is the seat of the higher functions of the brain—reasoning, forethought, problem solving, emotional control, and so on. It is the part responsible for personality, for who we are.
At the base of the brain, descending from it rather like an elevator shaft connecting the brain to the spine and the body beyond, is the oldest part of the brain, the brain stem. It is the home of our more basic operations: sleeping, breathing, keeping the heart going. The brain stem doesn’t get a lot of attention in the popular consciousness, but it is so central to our existence.
The most important component of the limbic system is a little powerhouse called the hypothalamus, which isn’t really a structure at all but just a bundle of neural cells. The name describes not what it does but where it is: under the thalamus.
Though only about the size of a peanut and weighing barely a tenth of an ounce, it controls much of the most important chemistry of the body. It regulates sexual function, controls hunger and thirst, monitors blood sugar and salts, decides when you need to sleep. It may even play a part in how slowly or rapidly we age.
The amygdala (Greek for “almond”) specializes in handling intense and stressful emotions—fear, anger, anxiety, phobias of all types. People whose amygdalae are destroyed are left literally fearless, and often cannot even recognize fear in others. The amygdala grows particularly lively when we are asleep, and thus may account for why our dreams are so often disturbing.
Just look around you now. The eyes send a hundred billion signals to the brain every second. But that’s only part of the story. When you “see” something, only about 10 percent of the information comes from the optic nerve. Other parts of your brain have to deconstruct the signals—recognize faces, interpret movements, identify danger. In other words, the biggest part of seeing isn’t receiving visual images; it’s making sense of them.
It continuously forecasts what the world will be like a fifth of a second from now, and that is what it gives us as the present. That means that we never see the world as it is at this very instant, but rather as it will be a fraction of a moment in the future. We spend our whole lives, in other words, living in a world that doesn’t quite exist yet.
Has it ever struck you that soap lather is always white no matter what color the soap is? That isn’t because the soap somehow changes color when it is moistened and rubbed. Molecularly, it’s exactly as it was before. It’s just that the foam reflects light in a different way. You get the same effect with crashing waves on a beach—greeny-blue water, white foam—and lots of other phenomena. That is because color isn’t a fixed reality but a perception.
The brain takes a long time to form completely. A teenager’s brain is only about 80 percent finished (which may not come as a great surprise to the parents of teenagers). Although most of the growth of the brain occurs in the first two years and is 95 percent completed by the age of ten, the synapses aren’t fully wired until a young person is in his or her mid- to late twenties.
The nucleus accumbens, a region of the forebrain associated with pleasure, grows to its largest size in one’s teenage years. At the same time, the body produces more dopamine, the neurotransmitter that conveys pleasure, than it ever will again. That is why the sensations you feel as a teenager are more intense than at any other time of life. But it also means that seeking pleasure is an occupational hazard for teenagers. The leading cause of deaths among teenagers is accidents—and the leading cause of accidents is simply being with other teenagers. When more than one teenager is in a car, for instance, the risk of an accident multiplies by 400 percent.
The difficulty is that there is no certain way of telling whether neurons in the brain are new or not. What is beyond doubt is that even if we do make some new neurons, it is nothing like enough to offset the kind of loss you get from general aging, never mind stroke or Alzheimer’s. So either literally or to all intents and purposes, once you pass early childhood, you have all the brain cells you are ever going to have.
His most notorious failure was Rosemary Kennedy, sister of the future president. In 1941, she was twenty-three years old, a vivacious and attractive girl but headstrong and with a tendency to mood swings. She also had some learning difficulties, though these seem not to have been nearly as severe and disabling as has sometimes been reported. Her father, exasperated by her willfulness, had her lobotomized by Freeman without consulting his wife. The lobotomy essentially destroyed Rosemary. She spent the next sixty-four years in a care home in the Midwest, unable to speak, incontinent, and bereft of personality. Her loving mother did not visit her for twenty years.
But the effects that he and others left in their wake lasted for years. I can speak with some experience here. In the early 1970s, I worked for two years at a psychiatric hospital outside London where one ward was occupied in large part by people who had been lobotomized in the 1940s and 1950s. They were, almost without exception, obedient, lifeless shells.
In 1997, Adrian Owen, then a young neuroscientist working in Cambridge, England, discovered that some people thought to be in a vegetative state are in fact fully aware but powerless to indicate the fact to anyone.
Owen believes that something in the region of 15 to 20 percent of people thought to be in a permanent vegetative state are in fact fully aware. Even now the only certain way to tell if a brain is working is if its owner says it is.
Chapter 5:
It’s curious that we always speak of our five senses because we have way more than that. We have a sense of balance, of acceleration and deceleration, of where we are in space (what is known as proprioception), of time passing, of appetite. Altogether (and depending on how you count them) we have as many as thirty-three systems within us that let us know where we are and how we are doing.
We are the only creatures that cry from feeling, as far as we can tell. Why we do so is another of life’s many mysteries. We get no physiological benefit from erupting in tears. It is also a little odd surely that this act signifying powerful sadness is also triggered by extreme joy or quiet rapture or intense pride or almost any other potent emotional state.
When you cry emotionally, the puncta cannot drain the fluid fast enough, so it overflows your eyes and runs down your cheeks.
Because we were once nocturnal, our ancestors gave up some color acuity—that is, sacrificed cones for rods—to gain better night vision. Much later, primates re-evolved the ability to see reds and oranges, the better to identify ripe fruit, but we still have just three kinds of color receptors compared with four for birds, fish, and reptiles. It’s a humbling fact, but virtually all nonmammalian creatures live in a visually richer world than we do.
You can experience this blind spot by means of a simple trick. First, close your left eye and stare straight ahead with the other. Now hold up one finger from your right hand as far from your face as you can. Slowly move the finger through your field of vision while steadfastly staring straight ahead. At some point, rather miraculously, the finger will disappear. Congratulations. You have found your blind spot. You don’t normally experience the blind spot, because your brain continually fills in the void for you. The process is called perceptual interpolation.
That’s quite remarkable—that a significant part of everything you “see” is actually imagined.
They were jawbones in our ancient ancestors and only gradually migrated to new positions in our inner ear.
Volume doubles about every 6 decibels, which means that a 96-decibel noise is not just a bit louder than a 90-decibel noise but twice as loud.
The reason we feel dizzy when we jump from a merry-go-round is that the gel keeps moving even though the head has stopped, so the body is temporarily disoriented. That gel thickens as we age and doesn’t slosh around as well, which is one reason why the elderly are often not so steady on their feet.
Smell is, in fact, a lot more important to happiness and fulfillment than most people appreciate.
An interesting and important curiosity of our sense of smell is that it is the only one of the five basic senses not mediated by the hypothalamus. When we smell something, the information, for reasons unknown, goes straight to the olfactory cortex, which is nestled close to the hippocampus, where memories are shaped, and it is thought by some neuroscientists that that may explain why certain odors are so powerfully evocative of memories for us. Smell is certainly an intensely personal experience. “I think the single most extraordinary aspect of olfaction is that we all smell the world differently,” Beauchamp says. “Although we all have 350 to 400 types of odor receptor, only about half of them are common to all people. That means that we don’t smell the same things.”
“People hardly ever lose their sense of taste,” Beauchamp told me. “Taste is supported by three different nerves, so there is quite a lot of backup. Our sense of smell is much more vulnerable.” The main cause of smell loss is infectious diseases like flu and sinusitis, but it can also result from a knock to the head or neural degeneration. One of the early symptoms of Alzheimer’s is smell loss. Ninety percent of people who lose smell through head injury never get the sense back; a smaller proportion, about 70 percent, who lose smell through infections suffer permanent loss. “People who lose their sense of smell are usually astounded at how much pleasure it takes out of their lives,”
An interesting and important curiosity of our sense of smell is that it is the only one of the five basic senses not mediated by the hypothalamus. When we smell something, the information, for reasons unknown, goes straight to the olfactory cortex.
“I think the single most extraordinary aspect of olfaction is that we all smell the world differently,” Beauchamp says. “Although we all have 350 to 400 types of odor receptor, only about half of them are common to all people. That means that we don’t smell the same things.”
Chapter 6
We choke to death more easily than any other mammal. The anatomist’s word for swallowing is “deglutition,” and it is something we do quite a lot—about two thousand times a day, or once every thirty seconds on average. about five thousand people in the United States and some two hundred in Britain choke to death on food each year.
But even using the most cautious estimates, choking is the fourth most common cause of accidental death in America today.
Unfortunately for us, bacteria in our mouths like that sweetness, too; they devour the liberated sugars and excrete acids, which drill through our teeth and give us cavities. We produce very little saliva while we sleep, which is why microbes can proliferate then and give you a foul mouth to wake to. Teeth have been called “ready-made fossils.” When all the rest of you has turned to dust or dissolved away, the last physical trace of your existence on Earth may be a fossilized molar.
The pituitary gland, for instance, which is buried deep within your brain directly behind your eyes, is only about the size of a baked bean, yet its effects can be—literally—enormous. Robert Wadlow of Alton, Illinois, the tallest human who ever lived to that point, had a pituitary condition that caused him to grow ceaselessly because of continuous overproduction of growth hormone. A shy and cheerful soul, he was taller than his (normal-sized) father by the age of eight, was 6feet 11inches tall at the age of twelve, and over 8 feet tall when he graduated from high school in 1936—all because of a little chemical overexertion by this baked bean in the middle of his skull. He never stopped growing and was just a fraction under 9 feet tall at his greatest eminence. Though not fat, he weighed about five hundred pounds. His shoes were a size 40. By his early twenties, he could walk only with great difficulty. To support himself, he wore leg braces, which caused chafing, and that led to a serious infection that grew septic and killed him as he slept on July 15, 1940. He was just twenty-two. His height at death was 8 feet 11.1 inches. He was much loved and is still celebrated in his hometown. It is clearly ironic that such a large body resulted from a malfunction in a minuscule gland. The pituitary is often called the master gland because it controls so much. It produces (or regulates the production of) growth hormone, cortisol, estrogen and testosterone, oxytocin, adrenaline, and much else. When you exercise vigorously, the pituitary squirts endorphins into your bloodstream. Endorphins are the same chemicals released when you eat or have sex. They are closely related to opiates. That’s why it is called the runner’s high. There is barely a corner of your life that the pituitary doesn’t touch, yet its functions weren’t even broadly understood until well into the twentieth century.
When heart muscle downstream of a blockage is deprived of oxygen, it begins to die, usually within about sixty minutes. Any heart muscle we lose in this way is gone forever. Cardiac arrest is when the heart stops pumping altogether, usually because of a failure in electrical signaling. When the heart stops pumping, the brain is deprived of oxygen and unconsciousness swiftly follows, with death not far behind unless treatment is quickly applied. A heart attack will often lead to cardiac arrest, but you can suffer cardiac arrest without having a heart attack. The distinction between the two is medically important because they require different treatments, though the distinction may be a touch academic to the sufferer.
Living a virtuous life doesn’t guarantee that you will escape heart problems; it just improves your chances.
John Wass, at the time we met, was particularly preoccupied with Addison’s disease. “It can be a very sad disease because the symptoms—principally loss of appetite and weight loss—are easily misdiagnosed,” he told me. “I recently dealt with the case of a really lovely young woman, just twenty-three years old and with a very promising future in front of her, who died of Addison’s because her doctor thought she was suffering from anorexia and sent her to a psychiatrist. Addison’s in fact arises from an imbalance of cortisol levels—cortisol being a stress hormone that regulates blood pressure. The tragedy of it is that if you correct the cortisol problem, the patient can return to normal health in as little as thirty minutes. She needn’t have died at all. A big part of what I do is lecture to general practitioners to try to help them to look out for common hormonal disorders. They are all too often missed.”
