Lorin Kleinman   Reading, writing, and occasionally eating.

It’s no secret that America has an obesity problem. And we know what we need to do about it: eat less and exercise more. Consume less fat. Rely less on animal products. If we can all just control ourselves and eat a low-fat, plant-based diet and get some exercise, everyone will be fine. Right?

That’s certainly the prevalent doctrine, dispensed by more or less everyone except for the authors of a trickle of low-carb diet books. (Confession: until recently, I considered Atkins and co to be utterly misguided.) But does it take into account how our bodies actually work?

Not according to Gary Taubes. In “Why We Get Fat,” he argues that it is carbohydrates, not fat, that cause obesity. An earlier book “Good Calories, Bad Calories” made this point in a much more verbose and technical way; this is his attempt at a more layperson-friendly (though certainly not unscientific) account.

Taubes regards the calories in/calories out model of weight loss as distinctly unhelpful. Sure: to gain weight, I have to eat more than I discard, but what causes this? Is every overweight person really just gluttonous and lazy?

He illuminates matters by describing a group of female rats whose ovaries had been removed. They began eating incessantly and quickly became quite obese. In some cases, though, they were held to their usual diets. These rats also became obese, but in addition, were lethargic, moving only to gather food. Greed and sloth: end of story?

No. Without ovaries, they had no estrogen. Estrogen helps regulate how fat is stored, and prevents it from landing solely in fat, as opposed to, say, muscle cells. In the absence of estrogen, most of the fat that these animals consumed was being stored in their fat cells. This meant that their bodies had no fuel to run on. So they kept eating. Forcibly prevented from eating, they lacked the energy to move. They weren’t getting fat because they were overeating: they were overeating because they were getting fat.

Humans are in the same position: incoming fat can be shunted into storage or treated as fuel.* (And estrogen works the same way, which is probably why women who have had hysterectomies often struggle with their weight .)  Taubes gives a somewhat technical but quite enlightening description of how we process food, with insulin in the starring role. We consume carbs, they’re turned into glucose, our bodies release a wave of insulin to cope with it. Insulin has a variety of effects, none very helpful to anyone who wants to lose weight. In particular, while insulin is elevated, it is impossible to burn anything other than glucose. It doesn’t matter how much fat is sitting around: we can’t burn it. In anyone with chronically elevated insulin, this is obviously a problem. Adding insult to injury, as we get older, we tend to become less sensitive to insulin, and some people become resistant. Obviously, this does not affect everyone equally (genetics plays a big role): we all know people who can eat piles of chocolate without gaining weight. “It may be easier to believe that we remain lean because we’re virtuous and we get fat because we’re not, but the evidence simply says otherwise. Virtue has little more to do with our weight than with our height,” Taubes says. Refined carbohydrates may not cause trouble everywhere, but where there are weight problems, Taubes says, carbs (and our hormonal response to them) are always to blame.

It is impossible to decrease carbohydrate consumption without increasing fat intake. Taubes is fully aware of the environmental and ethical disadvantages of a heavily meat-based diet, though he does not offer a solution. He does, however, address the widespread claim that the key to both weight loss and good health is a low-fat diet. Rather shockingly, he makes a convincing case that its purported beneficial effects are not supported by science.  (There is a revealing discussion of how the government came to claim that they were.) On the contrary, studies seem to show that people on low-carb, high fat diets have improved triglycerides and HDLs. As he points out, for a very long time our species lived chiefly on the fattiest meat it could find: the idea that we require carrots and orange juice isn’t entirely obvious. He dispenses with exercise similarly handily–while unquestionably very important, exercise does not seem to contribute much to weight loss.

David Kessler recently made clear that given that our brains treat combinations of sugar, salt, and fat more or less like heroin, judgmental harumphing isn’t a reasonable response to the obesity crisis. Given the large, intense–and utterly useless–guilt-fest that this country’s discussion of weight still is, this book couldn’t come at a better time.

*This is a simplified description: please do not treat this essay as an endocrinology manual.

A woman tries to walk across a room, but collapses. Another suddenly goes blind, for no obvious physical reason. Victorian hysteria, clearly a product of a time when women lived highly constricted, repressed lives. A veteran suffering from PTSD, on the other hand: doubtless a real disease, immutable, applicable in all situations and cultures. Not so, says Ethan Watters, who convincingly argues that all mental illnesses are circumscribed and molded by the cultures in which they occur. A person who is distressed will express it by drawing from whatever pool of symptoms is available in his culture–which may well be entirely different from what is available in my culture.

In Crazy Like Us: The Globalization of the American Psyche, Ethan Watters, a veteran journalist who presented a scathing indictment of the recovered memory movement in Making Monsters, examines four illnesses in four parts of the world: anorexia in Hong Kong, PTSD in Sri Lanka, schizophrenia in Zanzibar, and depression in Japan.

These four illnesses (and cultures) are quite different from each other, but share something important: none of them looked like the accepted Western clinical definition of the disease. Anorexics in Hong Kong did not believe that they were fat, trauma sufferers in Sri Lanka tended to describe physical symptoms and damage to family relationships rather than psychological problems, schizophrenics in Zanzibar were believed to be possessed by spirits, and in Japan, milder forms of depression were not viewed as an illness that required treatment.

Watters describes a world far from the definitive-sounding edicts of  the DSM (the diagnostical and statistical manual of psychological disorders, the handbook of Western psychology); one in which distress is signaled in an enormous variety of ways. “The simple but mind-bending truth,” the anthropologist Allan Young explains, “is that mental illnesses such as PTSD can be both culturally shaped and utterly real to the sufferer.” This world collides unhappily with the immutable-disease view of much of the Western mental health establishment.  (Anne Fadiman’s The Spirit Catches You and You Fall Down makes a good companion read.)

Western health professionals increasingly treat patients throughout the world, and Watters suggests that they are often far less helpful than they believe. A DSM-trained therapist, unwilling to consider that a Hong Kong anorexic does not believe herself fat, is unable to hear what the patient is actually saying. This is one problem with the globalization of the DSM. An even larger concern is that in the course of describing an illness, particularly if the description is dispersed widely throughout a culture, therapists may actually create an illness where it did not exist before. The local expressions of mental illness begin to disappear, and the clues that could have been gleaned from them are lost.

Crazy Like Us is not a polemic against Western mental health care: it is clear that competent Western therapists can be very helpful, under the right circumstances. It is equally clear, though, that they can be distinctly unhelpful under the wrong circumstances, when they fail to understand that their definitions are not universal.

This is especially clear in Sri Lanka, as American therapists rush to the scene of the tsunami, insisting that the local population has no understanding of trauma, and no idea how to treat victims. The psychology professor Ken Miller suggests that we consider the opposite scenario, with Mozambicans telling 9/11 survivors which rituals they need to engage in to sever their relationships with deceased family members. That the therapists earnestly believe themselves to be doing good makes these scenes no less disturbing. They explain that large segments of the population will fall victim to PTSD, and that it is not necessary to understand Sri Lankan culture to make this prediction. (There is an obvious connection to Watters’ previous work, with echoes of the victim mentality that characterized the recovered memory movement in these PTSD predictions, as well as in the medicalization of very minor depression in Japan. Human beings occupy a large spectrum, from fragility to resilience, and it’s not clear why fragility should be the default option.) These therapists are, of course, wrong: Sri Lankan history is sadly full of tragedy, and Sri Lankans have developed specific and effective methods of coping with it.

In all of these cultures, a shift is underway to a more Western view of the mind. Watters believes that a society is most susceptible to this influence when it is under a great deal of strain: the Chinese takeover in Hong Kong, for instance, or the tsunami in Sri Lanka. These changes do not happen on their own, but tend to be encouraged by outside agencies. The most striking instance that Watters describes of Western intervention is a successful attempt by a consortium of pharmaceutical companies to change the definition of depression in Japan, through an enormous and society-wide campaign. The high regard in which U.S. knowledge is held in much of the world makes such attempts to influence local mental health practices particularly effective–and dangerous.

From the U.S. point of view, the culture-blind promotion of Western ideas on the mind could appear to be a good thing. Shift your vantage point a bit, though, and these efforts look misguided and even harmful. This is a brilliant and genuinely paradigm-shattering book.

At a party the other day, a volunteer for the National Museum of Natural History described a visitor to the Hall of Human Origins. The young woman looked at a male skeleton and noted that the rib cage narrows as it moves downward.  She pointed to a particular spot and asked if that was where the rib was removed to form woman. She was not joking.

Would that this kind of ignorance, of even the most basic facts of science, were an anomaly. As Skeptics Society founder Michael Shermer has observed, the world is decidedly more rational than it used to be: many fewer people believe in witches, for instance.  But pseudoscience persists.

In Denialism: How Irrational Thinking Harms the Planet and Threatens Our Lives, Michael Specter examines five examples of this way of thinking. Leaving aside  the more common bugbears of skeptics–creationism, global warming denial, alien abduction claims and their ilk, which have been amply documented elsewhere–Specter discusses the fear of science and its disastrous intersection with vaccines, genetic engineering, alternative remedies, race and human origins, and synthetic biology.

The most infuriating, and strongest, section of the book concerns vaccines, and the very determined and deeply misguided people who oppose them.  Their beliefs originated with a journal article which linked vaccines to autism, and which has since been thoroughly discredited. Last year, I found myself in conversation with a woman–an EPA employee, no less–who said that clearly it could be no coincidence that she knew of several children who had been diagnosed with autism soon after being innoculated. I barely responded, being horror-struck but insufficiently informed.  Had I read Specter’s book, I would have pointed out that vaccinations and autism diagnoses tend to take place at the same age (between one and two), as well, of course, as that even a non-scientist EPA employee should know the difference between correlation and causation.  (Of course, that assumes that these parents remember the timing correctly. Specter is sympathetic to the leagues of desperate and confused parents of autistic children, who want an explanation, any explanation, for the plight of their children.)

Denialism is one of a number of interesting current books that allude to the great difficulties we have in gauging risk. Vaccine deniers, while giving entirely fictitious warnings about vaccines, do not tend to consider what happens in their absence. As Specter demonstrates, the pre-vaccine world was far from a naturalistic paradise. (In the developing and often still pre-vaccine world, around 200,000 children died of the measles in 2007. This represented a significant decline in measles deaths–from c. 750,000 in 2000–which of course will not continue if the anti-vaccine lobby has its way.) Specter does not deny that caution is necessary and important, and that scientists can be wrong and even occasionally criminal.  But he depicts a world in which the pendulum has swung so far onto the side of caution that the joys of scientific discovery have practically been forgotten, and the truth is almost incidental.

The world of natural remedies is no less filled with fraudulent claims, and many of these (largely unregulated) substances are not only ineffective, but can actually be harmful. I know this from my own experience: working at a health food store, I regularly saw people looking for “natural” remedies to treat what were clearly real health problems requiring real medicine.  In South Africa, the Mbeki government denied a connection between HIV and AIDS, refusing to provide antiviral drugs and causing hundreds of thousands of deaths in the process.

Pseudoscience can be merely irritating, the realm of UFO nuts and astrologers. But as the families of South Africans killed by AIDS, as the parents of any unvaccinated child who has succumbed to a preventable disease know, it can be deadly. In Denialism, Specter issues a clarion call for a rational world view.

Open google and type in “HeLa cells,” and a million and a half hits appear. This is because these cells are used and known universally throughout the medical world: far, far more than any other cell line. What has been much less well known is that HeLa stands for Henrietta Lacks, the woman from whom the original cells were taken. In The Immortal Life of Henrietta Lacks, Rebecca Skloot–a born storyteller–set out to tell both stories, Henrietta’s and the cells’.

In 1951, Henrietta Lacks, a poor African-American woman living in Baltimore, was diagnosed with a virulent form of cervical cancer, and began receiving treatment at Johns Hopkins. During the same period, scientists had been trying to culture an “immortal” cell line: a line of cells that would survive for an extended period of time in the laboratory. All of their attempts had failed.

Without the knowledge of Henrietta or her family (a common practice), doctors took samples from her cervix and sent them to a lab to culture. Several days later, it became clear that they had finally found an immortal cell line–HeLa, as it was named, following the conventions of the time, multiplied rapidly and was virtually indestructible. By the time Henrietta died, eight months later, her cells were famous.

In the intervening years, HeLa cells were used for everything from the development of the polio vaccine to testing how cells survive in space. But Henrietta’s family did not learn of the cell line until decades later, and then were repeatedly frustrated in their attempts to pry information from the medical world, which rarely told them anything, and provided information of only the most technical kind.

The family’s difficulties were exacerbated by both their scientific illiteracy and their timidity about challenging doctors. Neither is a condemnation: in a country where the reality of evolution is still being debated, the Lackses’ failure to understand cells is hardly shocking. Nor is it surprising that they felt unable to stand up to the vastly better-educated doctors at Johns Hopkins.

Nonetheless, one of the most haunting passages in the book describes a conversation between a Hopkins researcher and Henrietta’s husband Day. Day believed the researcher to have said that Henrietta was still alive at Johns Hopkins and being experimented on. He asked no questions of the researcher, and issued no demands. The value of both scientific literacy and a middle-class sense of entitlement is compellingly clear.

As HeLa cells made vast contributions to medical knowledge and large profits for medical companies (though never for Johns Hopkins), Henrietta’s family remained extremely poor, often unable to afford health insurance. Resentment and confusion grew within the family, and Henrietta’s daughter Deborah–Skloot’s lead character, who became a friend to Skloot over the ten years she spent working on the book–was driven almost to a nervous breakdown.

Finally, though, the family began to learn the facts surrounding HeLa. A sympathetic Austrian researcher led Deborah and her brother to a bank of freezers containing their mother’s cells. Deborah warmed a vial in her hands. “You’re famous,” she whispered. “Just nobody knows it.” Thanks to Skloot’s marvelous book, they do now.

Many of the loftier things in life rest on surprisingly mundane details. Think of democracy: it’s a very big idea, but can be undone by very small administrative errors. A few years ago in Maryland, a local election official forgot to put the cards needed for voting machines into the supply boxes for some polling places. Those polling places became fully functional hours late. In effect, this means that people were disenfranchised. What that election official needed was a checklist.

In The Checklist Manifesto, Atul Gawande makes the case that most complex situations are helped by checklists. A well-designed checklist, as he envisions it (and as the brilliant checklist writers of Boeing envision it) is not exhaustive, but covers the most important and easily forgotten details of a procedure. Equally importantly, it fosters teamwork among the people performing the procedure, whether they are medical staff in an operating room, or an airline crew flying an airplane. It does so in part by mandating that all participants introduce themselves to each other, which not only creates a sense that they are part of a team, but can also embolden the less-powerful members to speak up when it is important to do so.

Gawande repeats the story of an Austrian girl saved from drowning that he rivetingly told in the New Yorker, and reveals that the hospital which saved her (in an extremely long and difficult series of medical procedures) had attempted to save drowning victims before, but had never succeeded: until they implemented a checklist, a detailed and well thought-out set of protocols for what should happen from the first moment when a drowning is reported.

The building trade is another example. Gawande describes how it has moulded itself in a world grown too complex to accommodate the traditional master builder system (in which one architect had control of all details of the building process). As he points out, it is rather miraculous that so many large buildings manage to go up with so little incident. Builders achieve this, you will not be surprised to learn, through an elaborate system of checklists. Gawande discussed this at the 2009 New Yorker festival.

Gawande also weighs in on heroism in an increasingly complex world. The Miracle on the Hudson, as he describes it, was due not to the sole work of the captain, but instead to the teamwork of the entire crew — which was guided by a set of checklists. Heroism, Gawande suggests, though occasionally the work of a single, inspired individual, derives more often from the disciplined teamwork of a group of people.

The Checklist Manifesto, though less focused on medicine than Gawande’s previous books, continues his work of bridging the knowledge gap between medical workers and everyone else. He is also, as in his past books, quite ready to admit to his own failings. He confesses that he only grudgingly adopted a checklist in his own operating room (he didn’t want to be a hypocrite), but now says that he has “yet to get through a week in surgery without the checklist’s leading [them] to catch something [they] would have missed.”

Sadly, no matter how much evidence accrues for the value of checklists, Gawande describes an uphill battle in persuading organizations to use them. It is to be hoped that this work will help change that.

This is an important book. It shows us how to do things, sometimes extremely important things, better, and that doing things better is not about what we think it is about. In fact, it is often vastly less glamorous and more mundane than we expect. In The Checklist Manifesto, Gawande shows us a kind of perfection. The kind of perfection achievable by flawed, disorganized, easily distracted human beings. It’s a beautiful idea.