I tried to live on 600 calories a day. Here’s what I learned about dieting and obsession.

I ate wax. I ate paper. I ate peanut shells and sunflower husks. Sometimes, for a snack, I'd mix table salt with oregano and paprika and pretend it was barbecued potato chips. I drank pots of black coffee and oceans of water. I spent much of my free time walking, however slowly, because it burned calories and kept me away from food.

In my early teens, I had an eating disorder. For approximately three years, from age 12 to 14, my life revolved around what I ate and what I could successfully avoid.

Have you ever tried to stick to a diet of 600 calories a day? For weeks, months, years at a time? The effort required is all-consuming, the pain brutal and constant.

An undated diary, probably from eighth grade. In it, I’d followed some beauty magazine advice about writing when and where I ate the item, what I was doing, and what mood I was in. (Caroline Zelonka)

Your head pounds from hunger, even in your dreams. You feel woozy when you stand up. You never go anywhere without a coat, except for when you force yourself to bear the cold, because your body expends extra calories to warm itself.

You're preoccupied with food, alternately fascinated and tortured by its sight, sound, smell, or mention. You read a book for school and can't remember its title the next day, but you certainly recall the extra half-bagel you greedily gobbled down while you were reading.

The first time I went on a diet, it was the 1980s. I was 12 years old and weighed 89 pounds. I was also 5-foot-3, almost the height I am now. I wasn't fat, not even close. I'd never been teased (not about my weight, anyway), nor felt any direct pressure to be thin.

But I was going through an early puberty, maturing mentally as well as physically, and dieting seemed, well, kind of fun. A teenage-y thing to do, and a shortcut to gorgeous.

"Your skin will clear up!" the magazines promised. "Your hair will be bouncy and glossy!" My hair was growing in frizzy, my hips jutting out at weird angles, and my face was suddenly pimple city. Beauty magazines put diet first and foremost, so there must be a connection.

I couldn't control what was happening on the outside; I was firmly convinced I was getting uglier by the day, and popular opinion seemed to reflect this. The Atkins-esque Doctor's Quick Teenage Diet promised to fix it in just two weeks.

I think I lasted five days before I cheated. But the dieting experience was transformative. Suddenly it didn't much matter if the cool kids wouldn't speak to me, or if they laughed at my thrift shop wardrobe, or that I felt overwhelmed by school and piano lessons and Girl Scouts and, most of all, trying to navigate the world as a socially awkward, pizza-faced freak of nature.

My entire set of problems was funneled into a single uber-problem: getting through the day on 600 calories. After a while, I ditched Dr. Stillman's low-carb plan in favor of a low-fat, low-calorie approach that matched the weight loss wisdom of the time. I started keeping food diaries, where I would record every bite I allowed myself or that my mom forced me to swallow. Every stick of gum, every apple, carrot, and watery bowl of oatmeal.

Math was never my strong suit, so I usually rounded up to the highest possible calorie count. And I did most of my eating in the earlier parts of the day, because the dinner table was treacherous and it was easier to burn off calories if I could consume them before dark. (Caroline Zelonka)

Have you ever tried to stick to a diet when people were actively encouraging you to eat? "You look like you could use another piece of pizza." "You can't leave the table until you finish your potatoes." "What's the matter? I baked these cookies just for you!"

I became a master at concealment and distraction. It's quite possible to "eat" an entire meal without swallowing one bite. (It requires a few napkins and some sleight of hand.) There are ways to spread out your food to make your portion appear larger. Or eat so slowly that the table clears before you make a dent in your meal.

Most of the time, nobody noticed. Eating is such a fundamental, pleasurable activity that people will assume you're doing it, even when no one's watching.

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One thing I loved about restricted eating was that social isolation — something I struggled with — suddenly worked in my favor. I stopped worrying about who would sit with me at lunch because I stopped going to lunch. I didn't care that I couldn't go slumber parties because, hey, who needed the temptation? If I could spend an entire day by myself — in my room with my air popper and stash of fresh fruit — I'd be happy.

At the time, one of the things I hated about my life was the weekends. My parents had purchased an old cabin on the Wenatchee River, and our family spent Fridays through Sundays working on the property, almost year-round. I dreaded going out there. In the offseason it seemed there was little to do besides chores and wandering around, and it meant missing football games, trips to the mall, hanging out.

But my eating disorder gave me a new perspective on the weekends. At the cabin, I had almost unlimited freedom to work off the calories I ingested. A 100-calorie breakfast could be followed by a 20-minute walk, a 250-calorie lunch offset by a 30-minute bike ride. This trade-off meant I could eat more. There was also an icy river nearby in case I wanted to indulge in some calorie-burning thermogenics. Plus, the fact that we had no running water or reliable electricity meant that when meals were over, food was essentially unavailable.

I quickly began to look forward to our weekend pilgrimages, because they made it so much easier to serve my master: the eating disorder.

(Caroline Zelonka)

You may be wondering: Where was the diagnosis, the tearful come-to-Jesus meeting with the parents, the hospitalizations and intravenous feeding? Many stories of anorexia have an element of this. But I was never seen by a doctor, and though my weight remained low, it never got to the point where my health was obviously at risk. Yes, I am sure my folks knew something was up, but they chose their battles carefully. Beyond the occasional highly supervised meal, they chose not to take action.

My mother, I surmised, may have had a few food issues of her own. She was the one who bought The Doctor's Quick Teenage Diet for me in the first place.

I was also the product of a different time, when 12-year-olds were regularly left to their own devices and nice middle-class girls were expected to deny their appetites, for food and other things.

Today, I'd likely be diagnosed with atypical anorexia, one of the DSM-5's five clinical examples of an "eating disorder not otherwise specified." Patients suffering from this disorder exhibit normal bodyweight but otherwise meet the criteria for anorexia nervosa, which include "persistent restriction of energy intake, persistent behavior that interferes with weight gain, and undue influence of body shape and weight in self-evaluation."

Back in the '80s, things weren't as nuanced from a medical point of view, either. I can't remember any discussion of weight or eating habits at my doctor visits. Nor anything related to mental health. I'm pretty sure then, as now, I experienced weather-related depression during the dark, drizzly, cloud-covered days that characterize much of the year in the Pacific Northwest.

I'm also sure I experienced a great deal of clinical-grade anxiety, with very few coping skills. Starting at age 10 or so, I often woke up with a generalized sense of dread. Waking up starving felt a little better. At least I could associate my pain with something tangible. And I had something to look forward to: food!

This might be a good time to bring up drugs. I didn't take them, but I know that if I'd had access to recreational Ritalin or Adderall I would have been all over it. I was already eating cotton balls to cut my appetite; I would have had no reservations about taking pills that promised the same thing.

And I could have used the energy. I was constantly worried that I wasn't moving as much as I should, and my sluggishness was sometimes attributed to illness or, more often, a "bad attitude." Speed would have come in handy in a number of ways, but luckily I had no idea it existed.

I did know that coffee existed, and though I wasn't crazy about the taste, I drank it constantly. I had to be near a bathroom at all times, but the inconvenience seemed well worth it.

One drug I tried was ipecac syrup, a family first-aid kit staple, used to induce vomiting. The bottle was tiny, so I drank it all. It worked. Oh, lord, did it work. I puked my guts out, but then spent the rest of the night in a panicked sweat, heart pounding and muscles quivering, I thought I might die. This particular feeling wasn't worth it.

Of course I collected diet tips, mostly from women's magazines and beauty books, but sometimes from accounts from World War II Europe, where people were fighting off hunger pangs for real.

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I tried swallowing wet cotton balls to fill my stomach, but then we ran out and I was afraid to ask my mom to buy more. I tried substituting mineral oil for butter on my popcorn after I read it was inedible and therefore calorie-free. I wore a rubber band around my wrist and snapped it whenever I felt like eating, hoping to create a Pavlovian negative association in my mind. The cotton balls and mineral oil tricks worked; the rubber band did not.

Staying away from edible foodstuffs also meant staying away from other things, and over time, I developed a sense of unworthiness, that I was destined to occupy an inferior and unwelcome place in the world. I began feeling I didn't deserve things: croissant sandwiches, leather shoes, sunny days.

Experiencing pleasure often made me feel guilty, but it also fed my eating disorder. If I could somehow convince myself I didn't need much in the way of food, that it could become more or less optional, I could keep this all-consuming pain going forever.

But I couldn't. The survivor in me knew, all along, that this was messed up. Starvation wasn't salvation, beauty wasn't everything, and nobody gave a rat's ass about how skinny I was. And I knew that if I kept it up the way I wanted, I might die.

I didn't have access to Google, but I do remember coming across a stat: that a good percentage of anorexics eventually succumbed to their disease. Googling it now, it's estimated to be around 10 percent — one of the highest death rates from any mental disorder.

Going into freshman year of high school, I also realized my grades would start counting toward my GPA for college admissions, and that studying while starving was a Sisyphean task.

And despite my best efforts to isolate myself, I managed to make a few friends at the end of eighth grade. I'd also started to babysit and clean houses, and because many of my gigs were on weekends, my parents let me stay home instead of going to the cabin.

By age 14, I started to crawl out of it. I wish I could tell you I had an "aha" moment when I realized there was more to life than eating cotton balls and worrying about my thighs. But I didn't. I still have food and body image issues, lots of them, and I don't think I'll ever be completely free of this particular neuroticism.

I started eating lunch at school again. An actual lunch, not an apple and a Diet Coke. I received a Spirit Week cupcake from a "mystery admirer" and decided this person might not think I was a pig if I ate it. I made the drill team. I got a part-time job at a travel agency. I wrote angsty essays and stories that made people laugh, and, for some unknown reason, I got a standing ovation at graduation rehearsal.

(At the time, I thought it was simply because my name started with a Z and I was the last to be called, but looking at the class roster I see this wasn't the case. Maybe it was a belated acknowledgement of my presence, or maybe it was just a goof. I will never know, but at the time, it felt good.)

I wouldn't say that I made a full recovery, but by senior year I had a much healthier relationship with food. It helped that I had more control of my life, my schedule, and my finances. (It may sound shallow, but having a wardrobe of store-bought clothes did wonders for my self esteem.) I didn't dread weekends anymore, and sometimes even looked forward to eating with my friends.

Speaking of friends, by senior year I finally had a social life. And that, I believe, was the tipping point. Recent research has shown that loneliness and isolation are likely contributing factors to addiction, and I've come to see my eating disorder as similar to an addiction.

It certainly met the criteria. My diet dominated my thoughts, almost completely. It caused me to neglect my schoolwork, relationships, and hobbies. I lied about what I ate, and I stole things to eat: coffee and, though I hate to admit it, cotton balls. I pursued the behavior despite negative consequences to my health and well-being.

In a funny way, though, it gave my life purpose and a sense of accomplishment. When I was starving, all other problems vanished by the wayside. I could be bullied, I could be screamed at, things I yearned for could be snatched away without explanation, but when I was really hungry, they didn't affect me. My pain was my own to control.

Starvation became my security blanket. As my disorder progressed, my mental state shifted to accommodate my behavior, another similarity to addiction. I was this way because this was the way I was. Fate had decreed that I suffer, like the Catholic martyrs whose stories I'd devoured as a child. There was an honor and a purity in self-denial, but it took strength to do it. And I could. Not perfectly, but better than most.

And sure, there was the remote possibility that all this dieting would turn me into the next Brooke Shields. But this was secondary to the prospect of having a relatively problem-free existence.

I might encourage others to consider the addictive element before they rush to conclusions about why a young girl might be restricting her food. I'd challenge them to consider the possibility that the disordered eating is the symptom, not the cause.

A lot of observers might think that when a teen girl starves herself, the media is to blame. I'd say that the media might show her the path, but the girl makes the journey under her own power.

Sure, I wanted to be thin and glamorous like Princess Diana, but there is no way I would have walked around in a shivering daze for three years if starvation didn't satisfy some higher-order hunger.

I still suffer from a sense of unworthiness. I'm still drawn to an ascetic lifestyle, still struggle with social anxiety. Only last year, in my mid-40s, did I make a vow to stop restricting what I eat. While I don't think a diet obsession is all bad, as far as obsessions go I realize I'm at risk of taking it too far. I don't dwell on this risk, because I believe dwelling on problems often magnifies them, but I am careful.

I still eat air-popped popcorn and watery oatmeal, and, God help me, I still like to chew on peanut shells. But my days of eating cotton balls are over.

Caroline Zelonka is an advertising copywriter with more than 20 years of experience. When she's not writing slogans and video scripts, she often writes about her life on Quora, a knowledge-sharing site where she's a four-time Top Writer and the most-viewed contributor in the anorexia and body image topics. Caroline's work has been published in Business Insider, Forbes, and Slate.

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