The first time I felt body euphoria was in an Old Navy dressing room. The floor was sticky with inexplicable customer gunk, a toddler was sobbing in the next stall and I was wearing jeans five sizes smaller than usual.

I gaped at my reflection in awe. It’s not just that the jeans fit; I could also see my collarbones, which had been hidden under layers of fat and tissue for so long that I forgot I had them. My jaw line was more pronounced, and my belly didn’t jut out the way I remembered it to.

I had lost more than 100 pounds, and I could see the difference right there in the mirror.

With euphoria came guilt. It upset me that I liked my new reflection so much, because I didn’t know why I was happy with it. For years, I had subscribed to the notion that defining women’s worth by their weight was a feminist cardinal sin. Like countless others, I had found self-love and acceptance in the arms of the body positivity movement.

It offered me a welcome respite from the stress of constantly looking at myself with a critical eye, as well as a counterattack to the once prevailing idea that shame gets bodies in shape (it doesn’t). So why was I so happy at the sight of my new, thinner shape?

I lost more than 100 pounds in two parts over 18 months, during two big stages of my life. The first occurred when I went from a depressed, overworked college student to a stressed, fully employed adult. I replaced meals with coffee and ate once daily – usually the easiest thing I could pop into the microwave after a 12-hour day. On top of my 9-5 job, my four-hour daily commute made finding any time for myself nearly impossible.

My body responded to my new environment by shedding 50 pounds, but even then I knew my weight loss wasn’t healthy. My stress had reached a peak, and all I could do was shrink in the face of it. I had no time for physical activity, and if I was lucky enough to get a day off, I was too exhausted to move anyways. The stuff I consumed could barely be called food; I ate quick meals rife with saturated fats and sodium that just made me more sluggish. Research backs this up: stressful jobs lead to poor eating, junk food makes us depressed and failing mental health becomes a roadblock to improving health.

I bristled whenever someone congratulated me on my weight loss. To accept outsiders’ compliments on my weight loss was to betray the body-positive ethos I had adopted.

And then, just as easily as I had adopted it, I threw that life away. Less than a year into my first full-time job, I quit to travel Europe for five months. Suddenly, I had a limitless resource of something I hadn’t had my entire working life: time. I could spend all day walking, climbing or hiking in a different country. I could stroll through local markets, relishing the hues and aromas of the displayed fruits and vegetables, to pick foods that made me happy and gave me the energy I needed to keep exploring. Regular physical activity, a Mediterranean-style diet and freedom to do as I pleased changed me, and I lost another 60lb.

When I came back home to the US, my family and friends were shocked by my dramatic transformation and my weight loss was only part of it. Yes, I was smaller, but I also looked happier. I was more confident and said stuff like: “You know what would be so fun right now? A bike ride.” I even got a cool haircut. My new body was a reflection of the new life I was living.

One of the biggest changes my friends noticed is how experimental and colorful my fashion sense has become, compared with when all I wore was an ensemble of leggings and a T-shirt. Being more confident helps, but buying cool clothes is just easier the less fat you are. Albeit I’m still a solid size 14, but the realm of possibilities for my wardrobe has vastly expanded from the ironically slim size-20-and-up rack I used to shop from. I can put more care into my appearance and feel more secure in the way I present myself to the world because I actually have options.

There’s just one thing, though. My new commitment to health has also bordered on obsession at times. I don’t want to fall back on my old habits, so I pore over the ingredients in everything I eat. I work out regularly, sometimes to the point I can barely move my muscles the next day. And when I can’t bring myself to push my limits again – just one extra set of crunches or lunges – I feel like I’m failing myself.

Maybe getting healthier has made me happier, but being so preoccupied with health can be my downfall. Orthorexia, disordered eating influenced by an obsession with “healthy” foods, is one symptom of the larger problem diet culture was born from. Being perfect is a never-ending game of moving goalposts, and we’re compelled to spend the rest of our lives chasing after it.

I’m still plus size, but I have become a more “socially acceptable” fat woman worth catering to. For once, I feel like my body has the right to exist because there’s less room for me to take up. Is that anything to be happy about? All I know is that I own a pair of jeans that fit, and I’ll stop to admire my reflection when I wear them.