Diet Culture Is Unhealthy. It’s Also Immoral.

This past fall, my daughter, at 20 months, became fascinated with her bellybutton. At every chance she got, she began lifting her T-shirt to joyfully point it out. The inference that Mama and Daddy had bellybuttons too was not far behind, and neither were further exploration efforts. But when she lifted my shirt, I could feel myself sucking in my stomach. I felt shame — and ashamed of my shame. And that’s when it hit me: I have to sort my head out, regarding my body, for the sake of my daughter.

My relationship with my body is, to put it mildly, fraught. I have not always, but I have usually, been fat. I have always hated that fact, although I have tried not to. I have been a so-called normal weight, by the standards of the draconian body mass index guidelines, only when I have been starving myself or eating a highly restrictive and often downright odd diet. Over the past year, I have lost nearly 50 pounds, prompted by a vague sense of obligation to shrink myself back down to size. As usual, the weight came off only with efforts so extreme that I hesitate to admit to them: Over the course of a month last winter, I didn’t eat for 17 out of 30 days.

And I am someone who knows better. I recognize all the reasons I shouldn’t do this. I recognize that the relationship between fatness and health is far from straightforward — that many fat people are healthy and many thin people are not, that the correlation between being fat and having certain diseases is complex and generally mediated by other risk factors, including poverty and the social stigma that keeps fat people from getting the health care they deserve.

I have long admired the work of fat activists — Marilyn Wann, Sonya Renee Taylor and Aubrey Gordon among them — and recognize that fat bodies can be not only healthy but also athletic, beautiful, sexy. I believe in the concepts of intuitive eating and health at every size — at least, for other people. I recognize that the vast majority of diets fail to make people any thinner or any healthier in the long term. I recognize that even if you are a fat person who would be healthier if you lost weight, you don’t owe it to anyone to do so; you don’t owe it to anyone to be healthy in general. And I know how much my internalized fatphobia owes to oppressive patriarchal forces — the forces that tell girls and women in particular to be small, meek, slight, slim and quiet.

I recognize all of this in the abstract. In practice, however, I struggle.

I have lately wondered how much my self-directed fatphobia owes to my career as an academic philosopher. More than one author has remarked that there is a dearth of fat, female bodies in academia in general and in philosophy specifically. Philosophy, with its characteristic emphasis on reason, often implicitly conceives of rationality as the jurisdiction of the lean, rich, white men who dominate my discipline.

We praise arguments for being muscular and compact and criticize prose for being flabby, flowery and, implicitly, feminine. When it comes to our metaphysics — our pictures of the world — we pride ourselves on a taste for austerity, or as W.V.O. Quine put it, “desert landscapes.” And what is the fat body in the popular imagination but excess, lavishness, redundancy?

I struggle as a philosopher to reconcile my image of my body with its task in the world of being the emissary of my mind. I think of it, tongue in cheek, as my body-mind problem. Often, I cannot bear the idea of sending out my “soft animal” of a body, in the words of the poet Mary Oliver, to fight for feminist views that are edgy and controversial and to represent a discipline that prides itself on sharpness, clarity and precision. I feel betrayed by my soft borders.

This false binary exists partly in my own head, yes, but also very much in others’: I was recently apprised of a caption on a portrait of David Hume, the 18th-century philosopher, in an introductory philosophy textbook: “The lightness and quickness of his mind was entirely hidden by the lumpishness of his appearance.” Thus have other fat philosophers been warned that our bodies may similarly mask our intellects.

The cognitive psychologist Steven Pinker isn’t a philosopher, but his latest book, “Rationality,” handily demonstrates the worldview that equates thinness with reason. After bemoaning the fact that rationality is no longer considered “phat” (as in “cool”), he chides the irrational doofus who prefers the “small pleasure” of chowing down on lasagna now over the supposedly “large pleasure of a slim body” in perpetuity. They “succumb” to “myopic discounting” of future rewards — an (ableist) term for short-term thinking, illustrated with a fatphobic example.

Such examples proliferate in philosophy too: The standard example of the much-studied phenomenon of akrasia, weakness of the will, is succumbing to a cookie. The natural human appetite for rich and sugary foods is thereby derided as not only contrary to reason but also something to be tamed, shunned, even shamed. The constant deprivation and, sometimes, sheer hunger of someone who sticks to a rigorous diet is envisaged as an unambiguously good thing and as an achievement, even a virtue.

Is it, though? As someone who recently dieted with some success (“success”), it is obvious to me that I’ve set a bad example for my now 2-year-old daughter — one that will only become more problematic over time, as she becomes more and more aware of what I am or am not eating. I have contributed in a small way to a society that lauds certain bodies and derogates others for more or less arbitrary reasons and ones that lead to a great deal of cruelty and suffering. (The most common basis for childhood bullying is a child’s weight.) I have denied myself pleasure and caused myself the gnawing pain and sapping anxiety of hunger.

These are all things we usually think of as straightforward ethical ills. Almost all versions of the family of moral theories known as consequentialism hold that pleasure is morally good and pain and suffering are morally bad. Even if this is not the whole truth of ethics, it is plausibly part of the truth.

And it has the superficially surprising implication that dieting inflicts real moral costs, real moral harms, ones we largely impose on ourselves (albeit under the influence of potent social forces). If the chances of long-term weight loss (and the supposed benefits and pleasures that conveys) are vanishingly small, then why do we keep doing it? I suspect the answer is not only habit and a false sense of obligation but also the lure of aspiration: a dieter’s perpetual sense of getting somewhere, getting smaller and thus becoming more acceptable, more reasonable, as a body.

But while philosophy in its current form may fetishize thinness, it also has within it the power to challenge these ideas and even to reconfigure our moral relationship to them entirely.

We are at a moment during the year when many people will try, and even regard themselves as duty bound, to go on a diet. But if dieting is a practice that causes a great deal of harm — in the form of pain, suffering, anxiety and sheer hunger — and rarely works to deliver the health or happiness it has long advertised, then it is a morally bad practice. It is plausibly not only permissible but obligatory for individuals to divest from it, to condemn it and not to teach it to our children, either explicitly or by example.

Instead, we might strive within ourselves to meet new and better “liberating duties,” to borrow a notion from Joseph Raz. In this case, the duty — for those of us fortunate enough to have the resources — is simply, or not so simply, to eat when we are hungry.

Kate Manne is the author of two books, including, most recently, “Entitled: How Male Privilege Hurts Women.”

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