For me to it was a combination of a lot of things. My mother was always restricting her food intake severely to try to lose weight and considered gaining weight a personal failure on her part, so I accepted that as normal. My father would make comments about my mother's weight which reinforced to me that gaining weight was bad. I was always very underweight as a child/teen and was praised for it while my sisters, family members, and friends who struggled with their weight were shamed for eating and for not being thin enough. I internalized that getting fat was a terrible thing and developed body dysmorphia where I believed and was constantly paranoid that I was obese and had fat rolls at 100 lbs and 6' tall. I felt like I couldn't control much else in my life, but that "dedication, willpower, and hard work" could make me thin. I eventually got into modeling which only served to reinforce my disordered thinking and habits. There was no one "why". It was a lifetime of internalized messages from family, community, media, and everywhere that combined in my mind to something that I could do to control my own life. Even if those messages weren't always directed at me or even intended, I saw how much it hurt my friends and family to be called fat and how hard they worked to try to get away from that pain and I was always worried that I was going to cross the line to start receiving that abuse myself at any moment.

It took me a long time and a couple of serious health scares to get myself back on track for healthy eating, living, and body image, but I've reached a good equilibrium now.