Sports Illustrated Swimsuit model Kate Wasley lamented on Instagram that a rude comment from a teacher drove her to years of "hard dieting."

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"In high school I was quite overweight, at least 8-10 kgs heavier than I am now on the right," the 24-year-old blond bombshell captioned a before-and-after snap. "I used to get a lot of comments about how I'd be 'hot' if I lost weight and that I had such a pretty face etc. people weren't necessarily mean to my face but the little comments stung as I was only 17 and the way I looked and what people thought of me was still a big deal. So one day after a teacher told me In front of all my friends that I 'probably wasn't as fit as I could be' and the same teacher on a different occasion telling me I was a 'good wind block' for my cold friend, I decided it was time for a change and I was sick of people subtlety making me feel like s—t about my weight."

The Aussie model explained that she never took comments about her weight too seriously because she knew she wasn't working out or eating healthily.

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"Though this behavior makes me cringe now because I know the effect that behavior has on your insides, overall I was happy and I didn't really know where to start when it came to weight loss," she said.

"I started dieting HARD," she continued. "I spoke to a few of the girls in my year who I'd look at and think were absolutely STUNNING. ...  I got what I needed from these girls in my year and a quick google and started my very first diet that was the 'detox' it consisted of something ridiculous like 800 calories and a DISGUSTING juice with every meal that the cheap box and my one google search had convinced me was healthy and give me the body I desired."

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"Fast-forward a few years and I had tried every diet in the world, high protein, protein only, detox's, juice cleanses and settled on one that I found worked and made me feel good, not eating," she revealed. "I was at a point where I didn't know how to eat more than that. I was stuck calorie counting my chewing gum and blending ice, lemon juice and spinach into a 'smoothie'. I would exercise until it hurt and omg I was fit."

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"I used to eat 800 calories a day which for a 6'ft girl that's used to eating upwards of 2000kjs a day exercising as hard as I did is stupid," she wrote.

Wasley explained that the thinner she got, the more self-conscious she became, and she refused to go out with friends for fear of succumbing to the temptation of food and drink.

Realizing that her diet was "unsustainable," she cut back on her hardcore workouts and went back to eating a healthy, balanced diet.

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"It's a journey and it's tough in today's society where the 'perfect' body is stuffed down your throat," she admitted, "[but] I'm much happier now that I've accepted my body. It was a hard thing to do."