When the tabloids chose to focus on a 19-year-old electing for a bilateral mastectomy, because they (the preferred pronoun) are non-binary transgender, the internet responded with predictable pearl-clutching and tired old tropes. Wannabe armchair psychiatrists were quick to denounce Opi Baron as “obviously mentally ill”, while the accusations that “being transgender is fashionable” still fly thick and fast (despite the first known British male-to-female transgender surgery being performed on an RAF pilot in the 1950s but, you know what they say, fashion comes back around).

Thousands upon thousands of women have breast enhancement surgery every year to alter the “natural” configuration of their chests to match how they would prefer it to look. One of my cousins underwent a breast enlargement a few years ago, and her family and friends were supportive, accepting her explanation that the procedure would increase her self-confidence. Yet when I announced that I wanted a chest reduction, I was met with horror and stony silence from certain members of my family. “You can’t.” Well, yes, I can. And when you’ve given 10 years of consideration to something, I think you can conclude you’ve thought about it pretty carefully.

The writer James Delingpole suggested starting a petition for me to keep them attached to my body, with the insistent headline: “We need to talk about Dr Jack Monroe’s breasts”. So, James, I’m ready to talk. Another journalist suggested that there should be Kickstarter funding for my own surgery, obsessed as the chattering classes are by other people’s bodies, as evidenced by the bloated monster that is the Sidebar of Shame, and the red-circled shrieks, screaming from the newsstands, about the odd crow’s foot or rogue patch of acne. Quelle horreur, people are people, after all.

I remember sitting over breakfast with my mum a few months ago, awkwardly trying to answer her questions about being transgender. “I just don’t want you to make any permanent changes that you might regret …” she started. I laughed and gestured to my 44 tattoos before gently countering that it might be too late to start with all of that. “You dye your hair, Mum,” I pointed out. She tried to look indignant, but that shimmery ash-blonde at 52? I wasn’t buying it. “We change ourselves in so many ways. We lose or gain weight. Get tattoos, piercings, get them removed, take them out. We dye our hair, change our clothes, paint our nails. Sure, these are small things, compared with what could be a major surgical procedure, but I just know I have to do this.”

I was heavily criticised by some users on Mumsnet for my “proposed removal of a pair of healthy breasts”, as though breasts are a trophy, and I am a fool to part with mine. Perhaps so, but this body dysphoria runs deep, and I would be a fool to tolerate it when I don’t have to.

A startling confession for a food writer: all through high school, I struggled with a severe eating disorder. It started as a control mechanism, at a school where I was the only one from my special-measures junior school to make it, the only one who was dropped off in a white Essex Fire Service Ford Transit van half a mile from the school gate every morning, clambering out of the back like an A-Team mascot, only with thick round glasses and a satchel. I struggled at school, socially, mentally, academically. I’m not organised, and I don’t cope well with deadlines, structure and routine. I’m chaotic. Always have been. And so I started to starve myself. It started with giving my lunch away, then skipping breakfast, then walking home from school instead of catching three buses, in a bid to be thinner, thinner, thinner. Being thinner would solve everything, I thought. I started walking to school too. Seven miles a day. I remember the day I could fit into my year-7 school skirt, with its 20-inch waist, at 15 years old. I remember my parents realising that I was cutting my dinner up and pushing it around my plate, piling it high at one side, seeing how gaunt and exhausted I had become. I remember spending PE lessons in the sick bay, collapsing during netball.

And I remember being told that if I didn’t start eating properly again, I would be sent to hospital, locked away, forced to eat through tubes down my throat. I remember sleeping in the library, upstairs where the sixth formers went, instead of going to my classes. I remember begrudgingly regaining weight. I remember the despair; nobody knew what to do with me. Not my form tutor, nor my kindly head of pastoral care and discipline. I remember confiding in my food technology teacher. I remember loving food tech because of the precision and the creativity, the weights and measures, the tiny glimpses of flavour. I remember taking my carefully crafted meals home and watching my parents enjoy them. I remember food no longer being an enemy, but a joy.

But with my new-found love of food came puberty. I gained enough weight that I began to menstruate. My breasts began to develop. And I hated it. I had been boyish and braless for 15 years and that’s who I was. I pretended my name was Adam as a young girl. I prayed to God at night that I would turn into a boy when I started to develop. Something was wrong, deep down, but I didn’t know what it was or how to fix it.

I started to bind my breasts. I wrapped bandages around them to hold them down. I didn’t want them at all. I thought they were ugly, messy, cumbersome. Not mine, not a part of me I wanted or identified as my own.

I have no connection with them. I feel nothing there, something I have had to explain gently to various lovers over the years, who can’t understand the disconnect, especially as the rest of my skin is hypersensitive. I’m still the only person I’ve met who can orgasm from the right touch to my wrist (I’m not going to tell you which one!). But my breasts are just not part of me at all. I bought my first chest binder at the age of 19. This isn’t a phase.

When I had my first appointment at the gender clinic earlier this year, I sat and talked completely openly to a doctor for the first time. That’s the thing about being trans that the armchair commentators can’t comprehend: it’s a condition, just like any other. Although our experiences are all different, there are symptoms, there are questions that need to be asked, and criteria that need to be fulfilled in order to reach a diagnosis.

My medical report diagnosed me as transgender. I have been on hormones now for eight months. I walk taller, laugh more, feel myself. I mostly, finally, fit in my skin. Friends have commented on how much more confident I am. I’m not spending days in bed in fits of darkness and depression. I eat what the hell I like. I like myself.

People can sit at home and pontificate about my body all they like. Free speech and all that. But it’s mine. And I know what I’m doing with it, and why I’m doing it, and it’s not up for debate. I’m not an object. I didn’t fall off a factory line. I’m a little bit female and a little bit male and unless you’re a doctor sitting there with my medical history in your hands, physiological and psychiatric, I’m not going to put myself in your hands.

You can tell me I’m not a boy until you’re blue in the face, but to quote my good friend, author and longtime trans activist Christine Burns, it’s as good as saying that the sugar is salt.

• This article was corrected on 19 May because it wrongly stated that the first male-to-female transgender surgery in Britain had been carried out in the 1940s. It was actually the 1950s