Chapter 1: You Don''t 1 You Don''t A sandwich can involve many things at once: lettuce, regret, tomatoes, fried tofu, maybe some pickles, slicks of butter, despair, ennui. Maybe you like sandwiches, though. The one I just described at least looked uncontroversial. Apart from (some would argue) the tofu, which no one could see from the outside anyway, there could be few overt signals in a big white bap that I was some kind of bourgeois arsehole--like the kind who lunches on "street food" made by white entrepreneurs in pedestrianized enclaves overrun by wooden forks. At least it signaled I was not the kind of person who doesn''t care about life and brings an underwhelming squirl of cold spaghetti out for lunch from a stained Tupperware box. Maybe you too like the idea that a sandwich seems honest, which was hard for me to project because I was supposed to be anorexic and that, as we know, is a textbook liar''s disease. I liked that the sandwich made my veins feel fuller after I''d fasted, under instruction, until four in the afternoon. I liked the way the not-so-sweet tomato juice turned the bread into a moist, acid sponge.

But then there are the things it is harder to like: the regret, the despair, the ennui. It seems likely there are aspects of this complex relationship with sandwiches you find more relatable than others. Perhaps you''d go for bacon and sourdough or a brand-name plastic bread. Perhaps you have never been clinically diagnosed with an eating disorder, and class yourself as only moderately disturbed by the meanings attached to your diet. It is extremely unlikely, though possible, that you typically take your sandwiches after fasting, under instruction, until four in the afternoon. The only reason I did that was because I was participating in a clinical trial, assessing the value of psilocybin-assisted therapy for anorexia patients. The research team had needed me to spend an extremely hungry hour in an MRI scanner. The instruction, then, was not to eat a thing until it was done.

I''d be amazed, the study coordinator insisted, by the difference hunger can make to regional brain activity. I took this to imply that any sins would probably find me out. Stolen mouthfuls would flourish under the scanner like love bites on my prefrontal cortex. This paranoia may have had something to do with the fact that until the study had started, most of my interactions with the team had revolved around proving my condition. I''d needed doctors'' notes to confirm my DSM-5 diagnosis, and to confirm that their own attempts at treatment had failed to undo it. A series of interviews and physical exams had been arranged to check that I was all the things you had to be: restricting my food (A); of a very low weight (B), and resistant to reversing this trajectory (C). Yet here I was, not entirely resistant to reversing this trajectory, or I''d never have signed up for the study. My presence was proof, in fact, of some commitment to a reversal--at least enough for me to have taken some powerful drugs.

Drugs so powerful, in fact, that on two of the three occasions I''d been given them, I''d started to believe I was dead. I''d been prepared to come back, after hours of what the researchers called "primitive agony," and see what more the mushrooms had to reveal. I''d returned, at the end of all this, to spend one last hour in a brain-scanning tube, hungrily watching videos of food and rating how much I enjoyed them. I was prepared to play along with the seemingly fruitless task of assigning numbers to fruit, of quantifying my feelings about how the flow of chocolate sauce compared with the churn of a pencil sharpener. More to the point, I was committed enough to be eating an actual sandwich. To have wanted to eat the sandwich even before the white coats finally gave me the nod at four. The urge to commit sandwich adultery when I was supposed to be anorexic was, I supposed, kind of funny. Had I not been there precisely because desire is a complex thing, I might also have found it quite comforting.

I might have wondered, in fact, if I''d cured myself just by signing up for the trial. I might have wondered if, now, when we were wrapping things up and I was wrapping my mouth around a sandwich, this meant the cure was almost complete. This kind of eating, after all, was a category violation of criterion (A)--the one where anorexics must restrict their intake of food. All I would need now was to eat enough to breach criterion (B)--the one about low weight--and I''d be DSM-5 -official happy. But like I said before, I was not sold on the idea that my daily struggle to eat was a struggle with food alone. My suspicion that it wasn''t was only reinforced by the food-free experience of hell I had been shown in psychedelic space. I had been given to believe that my problem might, for example, have something to do with an overwhelming sense of the pointless; the exhaustion of any belief that life was in fact worth feeding. There are people who would never eat a sandwich, I thought, but whose body weight, for whatever reason, never reaches "very low.

" Sometimes these people are so resistant to eating sandwiches that the mere invitation to do so makes it hard for them to breathe. There are also people who really, really do not want to eat sandwiches but for whatever reason eat them anyway. No one calls these people anorexic, and therefore no one offers them therapeutic shrooms, yet still we all have something in common. We all have relationships with sandwiches that give us some level of grief. People like me, who had been through (A), (B), and (C), and were now engaged in eating, were not supposed to relate to these other people''s complex relationship with sandwiches. The DSM-5 is not interested in collapsing its own boxes. The DSM-5 will try to tell you who you are or who you have been, not the nature of your experience. The DSM-5 would like to know if you are a person who wants to eat, or if you are a person who doesn''t.

It doesn''t acknowledge that you can want, and be suspicious of, the same thing at once. It doesn''t care if you want the tofu, the lettuce, and the bread, but not the despair or ennui. It doesn''t care if you want to get better, but only if it''s possible for life to get better too. It certainly doesn''t care if, after a large dose of mushrooms, you decide you want to be nourished, but still are not quite convinced that being nourished will be worth it. This, in any case, was the state in which I looked forward to eating my sandwich: one of consent to at least finding out if things could be better than they were. This finding out, I recognized, would require me to eat, and eating, as we know, can be nice. Eating, though, was no guarantee that anything much would change but my weight. In my experience of more orthodox eating disorder treatment, many professionals insist it is objectively possible to feel better simply by eating.

They have a pet experiment to prove it--a study conducted in the 1940s. I thought about this study as I bit into the bread. A few weeks into my course of group "therapy" on an NHS treatment program, the group was treated to a special educational session with a dietitian called Harriet. Harriet could hardly wait to tell us about the Minnesota Starvation Experiment--a study she told us repeatedly that she loved . Harriet wished they could replicate the study today but "you''d never get the permission." This maybe should have raised some red flags about Harriet. Still, we heard her out. Heard her present the evidence for why "feeding first" was the way to cure an eating disorder.

The Minnesota Starvation Experiment took place toward the end of the Second World War. In 1944, civilians in occupied Europe had been starved, and needed to be re-fed. Those who hadn''t been blasted to bits had been living, just about, on mere bread and potatoes, and only God, at this point, knew what their shrunken stomachs could handle. In a bid to establish the optimal diet for bringing a person back to life, the American scientist Ancel Keys set about designing an experimental rehearsal of the refeeding process. For this, he needed healthy subjects to refeed, which meant mercilessly starving them first. The thirty-six test subjects in the Minnesota Starvation Experiment had been chosen from a pool of male volunteers. For six months, they were subjected to a "war conditions" diet, built around cabbage and potatoes with splashes of bean-and-pea soup. Quantities were controlled right down to the drops of vinegar on salad.

As the participants were progressively deprived over the weeks and their bodies began to eat themselves, a curious thing began to happen to these otherwise "normal" men: All of them--Harriet actually beamed at this part--began to act like anorexic girls. Which is to say, as their bodies underwent the biological assault of malnourishment, their minds grew erratic, impatient, and, crucially, weird about food. As their blood emptied of sugar and protein, the Minnesota men squirreled cookbooks under their beds and sliced thimbles of food into flakes. Like would-be ballerinas they mastered ritual eating and perfected bad moods. On excursions from the research facility, they watched other people eat in restaurants with a lunatic kind of joy. The friendliest souls turned solipsistic, bickered, bitched, bore grudges, made threats. Which concludes, Harriet told us, that behaviors like this could only have been side effects of hunger. We in the group could stop wasting our time worrying that we needed to fix our relationships with our mothers, with our thighs, with adulthood, with men, or whatever it was that kept us awake.

These were me.