If a cold is treated energetically it will get well in seven days, while if left to itself it will get well in a week.
Royal Navy commander W. A. Hopkins
Archie Cochrane was an esteemed Scottish medical doctor who died in 1988. He inspired the creation of the Cochrane Collaboration (now known simply as Cochrane), an international organization that organizes medical research systematically and produces what many believe is the most trusted source of evidence. He was also a doctor in a prisoner-of-war (POW) camp during the Second World War. He wrote about one of his experiences here:
I was usually the senior medical officer and for a considerable time the only officer and the only doctor. (It was bad enough being a POW, but having me as your doctor was a bit too much.) There were about 20,000 POWs in the camp, of whom a quarter were British. The diet was about 600 calories a day and we all had diarrhea. In addition we had severe epidemics of typhoid, diphtheria, infections, jaundice, and sand-fly fever, with more than 300 cases of “pitting edema above the knee.” To cope with this, we had a ramshackle hospital, some aspirin, some antacid, and some skin antiseptic.
The only real assets were some devoted orderlies, mainly from the Friends’ Field Ambulance Unit. Under the best conditions one would have expected an appreciable mortality; there in the Dulag I expected hundreds to die of diphtheria alone in the absence of specific therapy. In point of fact there were only four deaths, of which three were due to gunshot wounds inflicted by the Germans. This excellent result had, of course, nothing to do with the therapy they received or my clinical skill. It demonstrated, on the other hand, very clearly the relative unimportance of therapy in comparison with the recuperative power of the human body. On one occasion, when I was the only doctor there, I asked the German Stabsarzt for more doctors to help me cope with these fantastic problems. He replied: “Nein! Aerzte sind ueberfluessig.” (“No! Doctors are superfluous.”) I was furious and even wrote a poem about it; later I wondered if he was wise or cruel; he was certainly right.
Of course, most POWs are not average people. The soldiers in Cochrane’s story were young and—at least before they were captured—healthier than most people. If the camp had been full of older and sick prisoners, there almost certainly would have been more deaths. This is what medical geeks like me call “selection bias,” because healthy people were “selected” to be soldiers in the first place. Still, the poor living conditions and rampant disease epidemics are bad for young healthy people, too, and even a good doctor like Cochrane expected many more deaths. Cochrane’s story shows us how amazing human bodies actually are. It is a funny thing that some of the most fascinating facts about the human body are not taught (or at least not taught in a way that students remember them) in medical school.
Here are a few facts about your body:
Your immune system deserves a closer look.
You can’t avoid the fact that millions of germs, viruses, toxins, and parasites enter your body every day, many of which want to attack you. When you breathe, they come into your nose, mouth, throat, and lungs. When you eat, they come into your stomach. And when you get a scratch, they get into your bloodstream. Without an immune system, some of these invaders would literally eat your flesh to the bone in a couple of weeks. That is why corpses—which don’t have immune systems to protect them—are actually eaten by parasites. Your immune system deals with these millions of daily invaders silently and effortlessly without your even being aware of it.
Your skin acts as a first line of defense against foreign invaders. Skin has lots of disease-fighting white blood cells in case you get a scratch. When you inhale harmful viruses and germs, mucus in your nose and throat also acts as a defense. The mucus in your throat takes in unwanted particles. Once absorbed, they are swallowed into the stomach, where your stomach acid kills them quickly.
In the unlikely event that some stubborn bacterium or virus gets past the mucus in your throat to your lungs, the lungs meet them with their own specially designed immune system. The microenvironment of the alveoli (tiny air sacs that make up the lungs) is very delicate and would be damaged if the immune system were constantly on high alert there. So the specially adapted immune system in the lungs remains in a steady-state mode, and kicks into full-on-attack mode only when germs are present.
If disease-causing germs get past the mucus in your throat to your stomach, the gastric acid down there will take care of them. Gastric acid is strong enough to kill most harmful bacteria that might get that far. Amazingly, the acid does not destroy the elements we require for our own nourishment, like sugar and fat, and it even helps digest protein. In some rare cases, potentially harmful bacteria or viruses manage to get through the stomach to the intestine, sometimes hidden within a piece of food. If that happens, helpful bacteria in the intestine usually eliminate them.
If some harmful germ escapes the mucus in the throat, the acid in the stomach, and the good bacteria in your intestine and makes it into the bloodstream, another line of defense gets activated. The heroes of the part of the immune system in the blood are the white blood cells, which I have already mentioned. There are different types of white blood cells and they are everywhere, about half a million per drop of blood. The number increases when you get an infection.
Big white blood cells called macrophages engulf invaders whole and essentially starve them to death, then digest them. If some germs escape the macrophage, another kind of white blood cell seeks out and kills the infected cells. These highly trained killers specialize in “seeking and destroying” any cells that have been compromised. A common type of white blood cell doing seek-and-destroy missions is the natural killer cell. The first time I heard the name “natural killer cell” I thought it was a nickname to explain these cells to people who are learning about the immune system. It is not: “natural killer cell” is the real name. Your immune system even has a memory, so the second time invaders come, it can mount its attack more quickly. This is why people only get some diseases like chickenpox once.
Besides protecting you from invaders, your body has an inner pharmacy that can reduce pain, combat depression, and generally make you feel good. Your body produces its own endorphins, which create the natural high that people report when running or doing yoga. Endorphins derive their name from two other words: endogenous, which means “produced within a system” (in your body), and morphine. Squish the words endogenous and morphine together and you get endorphin. An endorphin is morphine produced inside your body. Really. Morphine and endorphin molecules are almost identical, and from the point of view of the body, they are identical. The same substance that some drug addicts are addicted to, or that doctors give to people in severe pain, is produced right inside your body.
Your inner drug factory also produces other drugs. It makes growth hormones, which help cells reproduce and regenerate (and that are illegal for athletes to inject); dopamine, which makes you feel good (and has the same effect as taking cocaine); and many other powerful chemicals. I’ll tell you a lot more about this in Part III.
I’ll finish this chapter by answering three questions that many people have when I tell them how amazing their bodies are.
If the body can heal itself, is it our fault if we get ill?
NO. We are all born with different bodies—different genetic makeups—and live in different environments. We have different tendencies to think certain ways. I was born in Canada, which is a rich country, where my mother was a fantastic cook who instilled healthy eating habits and my father insisted on exercise, hard work, and high standards. And mostly I’ve been blessed with great loyal friends. I had little control over those things, and they gave me some healthy habits and a good social network.
At the same time, the high expectations placed on me made me feel anxious sometimes. I didn’t have much control of that either. Just as I didn’t have control over most of my background, you didn’t have control over yours. And even if you did have control over something you did, blaming anything or anyone—including yourself—will not change it. In fact, blame is likely to increase your stress and make you less healthy. What matters is that your body is amazing, and no matter what your current health status is, chances are you can improve it, even if only a little bit. (The one slight caveat to this answer is people with very serious or terminal illnesses. Yet even in these cases the right attitude can bring peace and happiness, and I talk about this in Chapter 10.)
If our bodies are so amazing, why do we age or get ill?
Despite all the wonderful discoveries that science has made, there are a lot of mysteries we have not cracked, including the details of the aging process. Unless you have neotenic complex syndrome (a real but rare disease that prevents people from aging) you will age and eventually die, because you are mortal. Considering how many bacteria and germs we eat, how much stress we put our bodies under, and how much junk we consume, it is actually pretty surprising that we are often illness-free.
If our bodies are so amazing, why do we need medicine?
Usually you don’t need medicine. Many of the “illnesses” that most of us get—things like back pain, mild depression, anxiety, ADHD, and minor injuries—go away without medicine. The fact that we often take medicine and then we feel better may lead us to believe that medication is necessary whenever we are sick. But the truth is that much of the time our bodies would have healed themselves even without drugs. In most cases our cold will go away whether or not we take vitamin C, our headaches will go away whether or not we take aspirin, and our mild depression will go away whether or not we take Prozac. If we want to know whether a medication is truly effective, we have to look at the evidence, which is the topic of Chapters 2 and 3.
Most of us don’t realize how amazing our bodies are. In fact, we have too many negative thoughts. Cognitive behavioral therapists say there is something called our “inner critic,” which automatically interprets things in a negative way. Here are seven common types of negative thoughts:
The vast majority are false, and even fewer are helpful. They are also a common cause of many mental-health disorders, so it is good to reduce them as much as we can. Cognitive behavioral therapy (CBT) helps people use new thought patterns to replace the negative thoughts affecting their feelings and behavior. There are many trials showing that CBT can help cure people who are depressed, anxious, and low in self-esteem—in large part by helping them transcend negative thought patterns.
I’m not a CBT therapist, but a CBT therapist taught me a very easy technique that often works very well. And it works quickly. I was complaining about some negative thought I was having. I think it was that I wasn’t feeling happy in spite of some recent achievements. His advice was:
Imagine that you are walking on the street and there are some mischievous small children running around who are no taller than your waist. Imagine one of them tries to steal your wallet from your back pocket. What would you do? You wouldn’t get upset, you would simply brush their hands away from your back pocket gently, yet very firmly and positively. Then you would forget it and carry on your journey. You can do the same thing with thoughts. If any negative thoughts arise that you don’t like, imagine you are brushing them away firmly the same way you would brush away a child’s hand from your wallet.
The next time a negative thought arises, realize it is probably not true and brush it away. Move on with your life to things that make you feel better. (Note to anyone not interested in how we get good evidence: skip Chapters 2 and 3 and move straight to Chapter 4.)