'Why Zebras Don't Get Ulcers' is a science book on stress, physiology and psychology targeted at the educated layman. The author draws from a vast array of scientific research and condenses it into 418 pages of rich, informative content on one of the biggest nemesis of the modern age - stress.
Why Zebras Don't get Ulcers, 3rd Edition (2004)
Robert M. Sapolsky
St. Martin's Griffin, New York
ISBN: 9780805073690
The book is divided into 18 chapters, each chapter devoted to a particular facet of stress and how it affects us on various levels. The interplay of physiology and psychology (or an oversimplified version be called as the mind-body connection) is the major premise of the book. Glucocorticoids are our protagonist. Another major premise is banishing the notion of 'stress is bad', and to convince the readers of 'it lies somewhere in between - exactly where is what we don't know for sure'. What is offered is education, and through that, a yardstick on how things spiral out of control, and how some of it may be ameliorated. The author puts it up succinctly:
This book is a primer about stress, stress-related disease, and the mechanisms of coping with stress. How is it that our bodies can adapt to some stressful emergencies, while other ones make us sick? Why are some of us especially vulnerable to stress-related diseases, and what does that have to do with our personalities? How can purely psychological turmoil make us sick? What might stress have to do with our vulnerability to depression, the speed at which we age, or how well our memories work? What do our patterns of stress-related diseases have to do with where we stand on the rungs of society's ladder? Finally, how can we increase the effectiveness with which we cope with the stressful world that surrounds us?
Each chapter except the last deal with some particular grouping of disease that afflicts people and then establishes the extent stress plays a role in it. Each one of them is deeply informative and a pleasure to read even when it is all sombre news told with a great sense of humour. The opening few chapters introduce key mechanisms - most importantly the endocrinal (hormonal) system of our body and how the brain and rest of the body interact in the face of stress. A major and rather surprising point made is how ill-adapted our bodies are to dealing with psychological stress. For any kind of stress, the general stress response is the same - liquidate resources to have a burst of energy supplied to our limbs for a run. Isn't running, literally, an impulse that our body gives us - to run into someone's face, or away from it? I've talked about it before too, and as more pieces of the puzzle piece together, I am inclined to think that I might give it a shot as well. Anyhow, after the basic mechanism of stress responses is established, most chapters can be read independently of each other with only some passing references to the information contained in the ones before them.
In each of the chapters, the basic function and workings of that system in the body is explained. Then, how the system deals with stress in normal conditions is explained. Finally, the long-term effects are elaborated. It is hard to keep ourselves from marveling at nature and its construction of the organic body. Take for example the rites of passage for the immune cells before they enter circulation. They have it tougher than anyone among us - with both positive and negative selection in their academy (Thymus Gland). Or that no cell in the human body is more than five cells away from a blood vessel. The human body, as an engineer would describe it, is a very complex dynamical system containing many smaller, interacting systems and regulatory feedback and feedforward loops. So, the author first proposes that we drop our belief that the body is meant to achieve Homeostasis (a static degree of optimality achieved by tuning one single knob or lever) - instead, it looks to achieve Allostatis - a dynamical balance that may be 'regulated in a zillion different ways, each with its own consequences'. This is by far the most important point to take in a general sense - there is no free lunch, everything bears a cost. Thus, the atomistic viewpoint of Homeostasis is supplanted by a holistic view of Allostasis and the costs of wear and tear termed as the allostatic load.
[stress-responses] They are generally shortsighted, inefficient, and penny-wise and dollar-foolish, but they are the sorts of costly things your body has to do to respond effectively in an emergency. And if you experience every day as an emergency, you will pay the price.
The body of the book proceeds from establishing key concepts to systems and diseases of the physiological realms, onward to the psychological realms and finally the social realms. We learn about how our bodies work and how stuff happens. Diseases like stroke, heart attacks, Voodoo deaths, diabetes, sudden graying of hair, dwarfism, depression, immune system diseases and their stress-link - whether stress causes them, or makes things worse - is discussed. We learn about the energy balance of the body, apple and pear body shapes, stomach ulcers and bowel movement (and lack of it). It is described why some people lose appetite while some others, may hog on food when stressed, why we crave for particular kinds of foods (often called comfort foods) when stressed and how that is good and bad. The causal links between the health of a mother when she was in the womb and the health of her child, post, and prenatal stress, what the absence of a caring mother can do, infertility etc. are then discussed.
Women are actually wired differently in some areas of the brain. That too is explained, and what it entails. Takeaway: men have simpler circuits there. Increased complexity in nature might imply increased capability, but also increased complexity might also cause increased susceptibility to instability. This has not only physiological consequences, but psychological consequences as well - for example, the fight-or-flight may give way to tend-and-befriend behaviors, or how stress-induced-anagesia may be triggered in men due to competition while it is the real activity that gets it going in women. Pain can be highly subjective - this is explained by amusing examples and circuit diagrams too (whatever pleases you, it is there in it).
Consider three scenarios involving pain. First, a soldier is in the middle of some appalling battle, people being slaughtered all around. He is injured - not life-threatening, but serious enough to warant evacuation. Second, consider someone with advanced liver cancer, administered an experimental drug. Within a few days, her gut hurts like hell, a sign of the drug killing the tumour cells. Or third, someone is abrading their rear end raw while enthusiastically having sex on a rough carpet. What do they all have in common? Their pain's not going to seem all that painful - the war's over for me; the drug's working; what carpet?
Finally, we get to other subtler, soft aspects like the station in society, the Socio-Economic Status and its link with stress and diseases, personality types, substance abuse and the problem with incomplete and excess of information. So, while many politicians are mocked for claiming poverty as being a state of mind (while philosophers don't draw that flak as no one really listens to them and that they argue a lot), we do see how some forms of poverty (and poverty amid plenty) do bear semblance to these notions. It's all inside your head - after a certain point. We learn how not only every individual human being is fairly unique and complex, but also how complex the social structure is and the many ways it interacts with us. It also offers insights of how changing the narrative can often change the course of life.
The last chapter can be read independently of the rest of the book if one can place sufficient faith in the author (or me, as a reviewer) and serve as a Pole Star to deal with the blues and other hues of modern life.
Each chapter feels like a field book in the domain - quick access to the overall mechanism for a quick peek. A lot about the human body is explained. However, what is not explained despite pointing it out is "why do we have bladders?". I think that is so that we can rest in a dry place and not wet ourselves in sleep. If our sleep was forfeit for the sake of passing the piss, how would we restore ourselves? And guess when I got that idea? When I rose from sleep one fine morning and was emptying my bladders. On the chapter of motherhood and children, it feels like every parent must read it.
...stressing a female rat in any number of ways while she is pregnant will cause lifelong changes in the physiology of her offspring.
Of course, none of that would help except make us shrug in dismay, make us paranoid that anything and everything that we do will trump up against us - or even marvel how, despite so much complexity, close to nothing goes wrong usually. There was a chapter in the book 'Nothing' wherein, the authors kind of got 'preachy' with things like 'Go out', 'Meditate'. That didactism is absent here. The author argues more or less rationally - at least tries to scare you into compliance if not anything else (heh!). He even cautions (and also cites the uncited) against overdoing stuff. For example, everyone tells you 'Exercising is good'. He goes on to tell that it is only under some circumstances - one of them being your willingness to do it - or else it may even be deleterious.
Exercise is stress reducing so long as it is something you actually want to do. Let rats voluntarily run in a running wheel and their health improves in all sorts of ways. Force them to, even while playing great dance music, and their health worsens...
This brings up a broader issue important to our era of lookin' good. Obviously, if you don't exercise at all, it is not good for you. Exercise improves your heath. And a lot of exercise improves your health a lot. But that doesn't mean that insanely large amountsof exercise are insanely good for your body. At some point, too much begins to damage various physiological systems. Everything in physiology follows the rule that too much can be as bad as too little. There are optimal points of allostatic balance... Throughout hominid history, if you're running 26 miles a day, you're either very intent on eating someone or someone's very intent on eating you.
Robert also enunciates that it is not the quantity, but the substance. A few good people are better than a hundred strangers (which might even be hazardous). Above all, this book reflects deeply on how we live (I as a reader am not completely western in my consumption style, but we are close). When there is no getting away with that kind of life, we may better pay heed to the advice of researchers (the research that is validated by other, independent researchers, that is). It also reflects on how policy making for the masses is such a complex task.
Science has been broken down as much as possible for layman consumption. Top that off with the witty and humorous style of the author, there are numerous opportunities to insert guffaws in the pauses while reading. For example, the author is explaining how some primates manage to live with less stress despite the odds by having a more realistic assessment of situations and better social affiliations. He suggests therapy as a solution and then:
It would seem relatively straighforward to pull together some sound psychotherapeutic advice for these unhappy beasts. But in reality, it's hopeless. Baboons and macaques get distracted during therapy sessions, habitually pulling books off the shelves, for example; they don't know the days of the week and thus constantly miss appointments; they eat the plants in the waiting room, and so on.
It is sometimes stupid, but very welcome. Clearly, if this book had been written at the time of dinosaurs, they too might have survived and flourished! But of course, teaching them how to read would have been a tedious task.
We as humans have a fascinating capacity - of inventing things inside our heads. We can do things that not many other species can do - and we can do in one package what many disparate species do.
In our privileged lives, we are uniquely smart enough to have invented these stressors and uniquely foolish enough to have let them, too often, dominate our lives. Surely we have the potential to be uniquely wise enough to banish their stressful hold.
It is a beautiful book, deeply informative and immensely entertaining. I would say it should be a must-read for all educated people, particularly the employed and the unemployed people. It is a fairly gentle reminder of what goes wrong and gives pointers to not give in. More so, because of its detail, it provides not just some tools, but also the context where they are useful and that is what sets it apart from the self-help pundits out there. It gave me enough food for thought to reflect on, some of which I've put up here.