Survival of the Sickest: The Surprising Connections Between Disease and Longevity. Jonathan Prince

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      Volumes of old medical texts are devoted to how and how much blood should be drawn. An illustration from a 1506 book on medicine points to forty-three different places on the human body that should be used for bleeding – fourteen on the head alone.

      For centuries in the West, the place to go for bloodletting was the barber shop. In fact, the barber’s pole originated as a symbol for bloodletting – the brass bowl at the top represented the bowl where leeches were kept; the one at the bottom represented the bowl for collecting blood. And the red and white spirals have their origins in the medieval practice of hanging bandages on a pole to dry them after they were washed. The bandages would twist in the wind and wrap themselves in spirals around the pole. As to why barbers were the surgeons of the day? Well, they were the guys with the razor blades.

      Bloodletting reached its peak in the eighteenth and nineteenth centuries. According to medical texts of the time, if you presented to your doctor with a fever, hypertension, or dropsy, you would be bled. If you had an inflammation, apoplexy, or a nervous disorder, you would be bled. If you suffered from a cough, dizziness, headache, drunkenness, palsy, rheumatism, or shortness of breath, you would be bled. As crazy as it sounds, even if you were hemorrhaging blood you would be bled.

      Modern medical science has been skeptical of bloodletting for many reasons – at least some of them deserved. First of all, eighteenth- and nineteenth-century reliance on bleeding as a treatment for just about everything is reasonably suspect.

      When George Washington was ill with a throat infection, doctors treating him conducted at least four bleedings in just twenty-four hours. It’s unclear today whether Washington actually died from the infection or from shock caused by blood loss. Doctors in the nineteenth century routinely bled patients until they fainted; they took that as a sign they’d removed just the right amount of blood.

      After millennia of practice, bloodletting fell into extreme disfavor at the beginning of the twentieth century. The medical community – even the general public – considered bleeding to be the epitome of everything that was barbaric about prescientific medicine. Now, new research indicates that – like so much else – the broad discrediting of bloodletting may have been a rush to judgment.

      First of all, it’s now absolutely clear that bloodletting – or phlebotomy, as it’s known today – is the treatment of choice for hemochromatosis patients. Regular bleeding of hemochromatosis patients reduces the iron in their systems to normal levels and prevents the iron buildup in the body’s organs that is so damaging.

      It’s not just for hemochromatosis, either – doctors and researchers are examining phlebotomy as an aid in combating heart disease, high blood pressure, and pulmonary edema. And even our complete dismissal of historic bloodletting practices is getting another look. New evidence suggests that, in moderation, bloodletting may have had a beneficial effect.

      A Canadian physiologist named Norman Kasting discovered that bleeding animals induces the release of the hormone vasopressin; this reduces their fevers and spurs their immune system into higher gear. The connection isn’t unequivocally proven in humans, but there is much correlation between bloodletting and fever reduction in the historic record. Bleeding also may have helped to fight infection by reducing the amount of iron available to feed an invader, providing an assist to the body’s natural tendency to hide iron when it recognizes an infection.

      When you think about it, the notion that humans across the globe continued to practice phlebotomy for thousands of years probably indicates that it produced some positive results. If everyone who was treated with bloodletting died, its practitioners would have been out of business pretty quickly.

      One thing is clear – an ancient medical practice that “modern” medical science dismissed out of hand is the only effective treatment for a disease that would otherwise destroy the lives of thousands of people. The lesson for medical science is a simple one – there is much more that the scientific community doesn’t understand than there is that it does understand.

      Iron is good. Iron is good. Iron is good.

      Well, now you know that, like just about every other good thing under the sun, when it comes to iron, it’s moderation, moderation, moderation. But until recently, current medical thinking didn’t recognize that. Iron was thought to be good, so the more iron the better.

      A doctor named John Murray was working with his wife in a Somali refugee camp when he noticed that many of the nomads, despite pervasive anemia and repeated exposure to a range of virulent pathogens, including malaria, tuberculosis, and brucellosis, were free of visible infection. He responded to this anomaly by deciding to treat only part of the population with iron at first. Sure enough, he treated some of the nomads for anemia by giving them iron supplements, and suddenly the infections gained the upper hand. The rate of infection in nomads receiving the extra iron skyrocketed. The Somali nomads weren’t withstanding these infections despite their anemia: they were withstanding these infections because of their anemia. It was iron locking in high gear.

      Thirty-five years ago, doctors in New Zealand routinely injected Maori babies with iron supplements. They assumed that the Maori (the indigenous people of New Zealand) had a poor diet, lacking iron, and that their babies would be anemic as a result.

      The Maori babies injected with iron were seven times as likely to suffer from potentially deadly infections, including septicemias (blood poisoning) and meningitis. Like all of us, babies have isolated strains of potentially harmful bacteria in their systems, but those strains are normally kept under control by their bodies. When the doctors gave these babies iron boosters, they were giving booster fuel to the bacteria, with tragic results.

      It’s not just iron dosing through injection that can cause this blossoming of infections; iron-supplemented food can be food for bacteria too. Many infants can have botulism spores in their intestines (the spores can be found in honey, and that’s one of the reasons parents are warned not to feed honey to babies, especially before they turn one). If the spores germinate, the results can be fatal. A study of sixty-nine cases of infant botulism in California showed one key difference between fatal and nonfatal cases of botulism in babies. Babies who were fed with iron-supplemented formula instead of breast-fed were much younger when they began to get sick and more vulnerable as a result. Of the ten who died, all had been fed with the iron-enhanced formula.

      By the way, hemochromatosis and anemia aren’t the only hereditary diseases that have gained pride of place in our gene pool by offering protection from another threat, and they’re not all related to iron. The second most common genetic disease in Europeans, after hemochromatosis, is cystic fibrosis. It’s a terrible, debilitating disease that affects different parts of the body. Most people with cystic fibrosis die young, usually from lung-related illness. Cystic fibrosis is caused by a mutation in a gene called CFTR; it takes two copies of the mutated gene to cause the disease. Somebody with only one copy of the mutated gene is known as a carrier but does not have cystic fibrosis. It’s thought that at least 2 percent of people descended from Europeans are carriers, making the mutation very common indeed from a genetic perspective. New research suggests that, sure enough, carrying a copy of the gene that causes cystic fibrosis seems to offer some protection from tuberculosis. Tuberculosis, which has also been called consumption because of the way it seems to consume its victims from the inside out, caused 20 percent of all the deaths in Europe between 1600 and 1900, making it a very deadly disease. And making anything that helped to protect people from it look pretty attractive while lounging in the gene pool.

      Aran Gordon first manifested symptoms of hemochromatosis as he began training for the Marathon des Sables – that grueling 150-mile race across the Sahara Desert. But it would take three years of progressive health problems, frustrating tests, and inaccurate conclusions before he finally learned what was wrong with him. When he did, he was told that СКАЧАТЬ