Some of the new research on possible causes of obesity is fascinating. New theories emerge continually, many of them at best inconsistent and at worst contradictory. But what interests me more is the debate that research sparks, which seems, at least in the popular arena, to be less about what actually causes obesity than about whose fault it is. It’s a subtle but important difference: the former is (largely, at least) a scientific question; the latter makes it a political or a philosophical one — and is, it seems to me, a thoroughly unhelpful approach.
The simplest and most obvious thing, which most Americans have done, is to blame fat people for the choices that made them fat. If we ate less and exercised more, as our ancestors did, then we’d weigh less. The logic comforts thin people (your obesity is your problem, not mine) as well as those who like to think themselves of scientific mind: calories in, calories out; it’s just simple thermodynamics — right?
But, as David Berreby writes in Aeon, scientific investigations into obesity consistently complicate that notion. Metabolisms vary. Some foods seem to change the body’s metabolism. So may environmental chemicals. Temperature and sleeplessness have an impact. A child born of an undernourished woman will carry a propensity to hold onto every calorie — and thus, if later immersed in abundance rather than scarcity, tend toward obesity, leading to what Jonathan C. K. Wells calls the “metabolic ghetto.” Industrialization, Wells argues, first created scarcity for the lower classes, which caused them to develop a tendency to store fat; now their descendants live in an environment rich with food, but are able to afford only food that also tends to promote obesity. Berreby explains:
If you or your parents – or their parents – were undernourished, you’re more likely to become obese in a food-rich environment. Moreover, obese people, when they have children, pass on changes in metabolism that can predispose the next generation to obesity as well. Like the children of underfed people, the children of the overfed have their metabolism set in ways that tend to promote obesity. This means that a past of undernutrition, combined with a present of overnutrition, is an obesity trap.
Perhaps most troubling is that even our domestic animals — even laboratory animals — are experiencing similar weight gain:
Consider, for example, this troublesome fact, reported in 2010 by the biostatistician David B Allison and his co-authors at the University of Alabama in Birmingham: over the past 20 years or more, as the American people were getting fatter, so were America’s marmosets. As were laboratory macaques, chimpanzees, vervet monkeys and mice, as well as domestic dogs, domestic cats, and domestic and feral rats from both rural and urban areas. In fact, the researchers examined records on those eight species and found that average weight for every one had increased. The marmosets gained an average of nine per cent per decade. Lab mice gained about 11 per cent per decade. Chimps, for some reason, are doing especially badly: their average body weight had risen 35 per cent per decade. Allison, who had been hearing about an unexplained rise in the average weight of lab animals, was nonetheless surprised by the consistency across so many species. ‘Virtually in every population of animals we looked at, that met our criteria, there was the same upward trend,’ he told me.
It isn’t hard to imagine that people who are eating more themselves are giving more to their spoiled pets, or leaving sweeter, fattier garbage for street cats and rodents. But such results don’t explain why the weight gain is also occurring in species that human beings don’t pamper, such as animals in labs, whose diets are strictly controlled. In fact, lab animals’ lives are so precisely watched and measured that the researchers can rule out accidental human influence: records show those creatures gained weight over decades without any significant change in their diet or activities. Obviously, if animals are getting heavier along with us, it can’t just be that they’re eating more Snickers bars and driving to work most days. On the contrary, the trend suggests some widely shared cause, beyond the control of individuals, which is contributing to obesity across many species.
And Berreby doesn’t even get into the problem of willpower itself — that the simple act of exercising one’s will saps it, that the sheer number of choices the typical Americans are required to make in a day wears down our ability to choose wisely. (I know: poor us. It’s a first-world problem — but then so is obesity.) And the resulting despair, lowered self-esteem, or whatever you wish to call it, further lowers our resistance to temptation.
Whatever the validity of any single theory, it seems clear that to blame obesity entirely on a failure of individual will is simplistic; other factors must be at work. But the fact that one answer is simplistic does not make its opposite any less so. It doesn’t automatically follow that individual will plays no part at all in weight gain, but Berreby seems loathe to discuss, for example, variations within similar populations in which choice may be a factor. Some people in similar situations gain more weight than others, and some do manage to lose weight and keep it off. Why?
Berreby writes a fascinating article, but he seems no less than his imagined opponents to be looking for someone or something to blame — be it biology, society, government, environment, or global corporations. He wants to find “the real causes of the trouble” so that we can fix it. But though he insists that we must do something even without all the information we need, he offers no specific ideas other than some vague thoughts about reforming the global food system — which is, he admits, “a tall order.” Color me skeptical. I agree that telling everybody to eat less and exercise more isn’t enough, but plopping down on the couch and tearing into another bag of Doritos while we wait for the reform of the global food system doesn’t seem any more productive. Gluttony may not be the only route to obesity, but it will sure get you there.
The comments on the article, which stretch on for approximately half the length of Wikipedia, dive straight into antagonistic oversimplification and remain there. Most lay the blame somewhere specific. “For me, the pervasive problem is…” Others simply insist that willpower isn’t the answer: “Believe me, I’ve tried everything. Those who say it’s just a matter of willpower don’t know what they’re talking about and can go perform a physical impossibility on themselves.” And on the other side, sarcastically: “Shut up, we’re getting fat because of magic, not because we’re eating more and moving less!”
The core of the debate is milennia old, though it has taken different forms: fate versus free will, original sin versus free will, individual choice versus social forces, nature versus nurture. I recall my high school AP English class, in which, after reading Oedipus Tyrannus, we debated whether human lives were truly governed by fate or by free will. The dilemma, I argued (being then nearly as contrary as I am now) was false: surely free will doesn’t mean we always get what we want, because the free will of others comes into play. You have your free will; they have theirs. Sometimes you lose. I don’t recall my teacher’s response except that I found it unsatisfactory. Whether she didn’t understand my point, or was irritated that I was disrupting her neatly designed lesson, or thought I simply wasn’t being any fun, I don’t know. But the debate went on. It still does.
Of course neither side can prove their principles; to every point there is a counterpoint. I’m reminded of Richard Feynman’s experience of hypnosis. As a young man, Feynman was inclined to believe hypnosis a scam, but being a good scientist (and being, well, Feynman) he decided to try it out for himself. He attended a demonstration by a hypnotist and volunteered to be a subject. And of course, once the hypnotist had gone to work, Feynman did precisely what he was told. He believed at the time that he was following orders simply to help the demonstration go more smoothly, and that the hypnotist wasn’t actually controlling him at all. Later, though, he realized that the key point was that he had gone along. If he had possessed free will, why hadn’t he exercised it? At the very least, he couldn’t prove that he had retained free will under hypnosis, and that therefore it hadn’t worked. Of course he still couldn’t prove that hypnosis really worked, either — but he was forced to take the possibility seriously.
Most of us, being less experimentally inclined than Feynman and considerably less comfortable with simply not knowing something, pick a side in the debate and stick to it — typically whichever one is most com. Why is it so hard to accept that, while we are free to make choices, our choices are constrained, and the efficacy of our actions is limited? Because it’s so much easier not to accept it. If we are free to choose, then we must also be responsible for our choices. But if our choices are constrained and their efficacy limited, then we cannot be held entirely responsible for their consequences. That isn’t quite a contradiction, but it’s a paradox. Westerners, at least, tend to be deeply uncomfortable with paradox.
Westerners seem also to be deeply uncomfortable with the idea that we can’t simply make things work. That we can shape the world to our will is a core belief of the modern era, and its corollary is that if we cannot shape the world, then it must be because we have no free will. It seems to be easier for us to give up the idea of free will, at least in philosophic principle and public policy, then to give up the conviction of our own efficacy. If we can’t blame fat people for being fat, then we must blame biology or history so that we can craft public policies to solve the problem — so that we can do something else. The impulse to want to do something is noble enough; what troubles me is the assumption that it’s surely going to work — and that if it doesn’t, that too must be somebody’s fault. Even Berreby, for all the complexity and confusion he offers, can’t seem to let to that assumption. “One possible response,” he observes, “…is to decide that no obesity policy is possible, because ‘science is undecided’. But this is a moron’s answer: science is never completely decided.” Yet he offers no specific prescriptions as to what we should do — while proactively blaming those who prescribe wrongly. “History is not kind,” he concludes, “to authorities whose mistaken dogmas cause unnecessary suffering and pointless effort, while ignoring the real causes of trouble.” True enough, but not entirely fair, and utterly unhelpful.
Berreby has described a problem so complicated that we ought at least to entertain the possibility that it is, on a grand scale, intractable — that it has so many interlocking causes and effects that we cannot untangle them, nor perhaps even identify them. But Berreby cannot, apparently, do this, and neither can any of the commenters whose responses I read (a tiny fraction, I admit, of the whole). It seems to me that his very argument — that people’s choices are limited, that free will does not have free rein, and that scientific knowledge is ever fallible — ought to shape his conclusions. Yet his faith in our collective ability to exercise our free will over ourselves is unshaken, and so he offers no more forgiveness to those who fail to exercise their free will with perfect efficacy over public policy than free will’s champions offer to the morbidly obese.
And forgiveness, I think, is crucial. Sometimes you can’t do much, but you have to do it anyway. We are bound to try, but with an acceptance that we are limited in our knowledge and in our abilities. And since we are limited, we are bound to be forgiving of failure — we must forgive others when they fail, and ourselves when we fail. And then we’re bound to get up and try again. It’s not a comfortable situation to be in, and I don’t know how anyone could find comfort in it without religion to explain and support it. But if there’s a “solution” to obesity, or to any of the other great debated problems of our age, I suspect that’s where it lies.