On Aug. 28, 2010 while walking at Missouri Western State University, she decided she'd had enough.
"Just walking out on the campus I was out of breath and I just knew I didn't feel good. That was it, I just had my ah-ha moment that I'm not going to do this anymore," said Fultz.
That's the day Mandy joined Weight Watchers.
She was determined to drop the pounds to get off high blood pressure medicine.
Fultz also wanted to be healthy enough to start a family.
"If I have kids I want to be able to play with them," added Fultz
But she didn't do it alone, she had the support from her husband, Joshua.
Together, they lost nearly 300lbs.
Fultz says she wouldn't have been able to do it without her husband by her side.
"When we have those days it's good to have someone there to say, are you sure you really want to eat that," said Fultz.
With his support she learned to cut back on sweets and make other healthy choices.
It wasn't just a diet, it was a lifestyle change.
"It's not ever gonna be over, it's just a continuation of eating better exercising and weight you know some of it's came back on so you just work to get it back off," says Fultz.
Fultz says she's now happier and more confident.
Looking back at old photos still shocks her.
"To look at that it's like wow how did I get that far, how did I let that happen," added Fultz.
Her advice for others is to start small and acknowledge that the weight didn't come on overnight, so it won't leave overnight.
"My goal is to help people see that it can be done," added Fultz.
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