"I was lazy, and I wasn't interested in exercise, I hated PE [physical education] at school and I spent most of my nights after school [sitting] on the computer."
Parry said she would avoid going out with friends, because she would often compare herself with their slimmer bodies.
"At first, I wasn't bothered about my weight," she said. "But all my friends at school had boyfriends and I never had one; no boys were ever interested in me."
But since leaving and becoming a sales assistant, the now 25-year-old has shed almost 40kg by training four to five times a week, and hopes to become a fitness instructor to help others follow her lead.
"I had it in my head that I wanted to lose weight and feel good about myself," she explained.
"Once you see results from all the hard work it makes you even more motivated to achieve more."
Parry said she used a personal trainer for six months, and made sure to include weight training and drop her diet of takeaway and late-night chocolate treats.
"I usually eat porridge for breakfast, tuna, rice and vegetables for lunch and then dinner usually consists of [vegetarian meat substitute] Quorn with potatoes and vegetables," she said.
Parry said she also refused to weigh herself, and now measures her weight loss and progress on how her clothes fit her body.
"I don't believe that the number on the scale represents anything at all," she said.
"It's just a number and in the past I've got to a point where I became obsessed with weighing myself and it made me unhappy.
"Fitness is something I am passionate about and I'd love to help others who don't think they can lose weight and feel good because you can achieve anything."
