Two years ago, Sarah Wolter looked unrecognisable.
At 166 kilos, the South Australian working mum lived a life of no exercise while consuming a high-calorie diet of carbohydrates and sugar.
Ms Wolter, who is now an incredible 83kg lighter, told Channel 7's Sunrise on Wednesday that she was always conscious of being "the big girl" and that her weight often held her back from doing certain activities in life.
After seeing a segment on the breakfast program several years earlier, Mrs Wolter decided to give the scientifically based CSIRO diet a try — and ditch the fads she'd attempted previously.
"Before the diet, I ate a lot of high-carb foods so bits of bread and butter," she told Channel 7. "One of my worst habits was snacking between meals. Lots of chips and crackers and cheese and that sort of thing."
The diet focuses on high protein consumption at every meal, with Professor Manny Noakes claiming that 25g of protein each meal was the secret for weight loss.
"Distribution of protein throughout the day, especially at breakfast, can really help appetite control and reduce cravings across the day," she said.
"Protein can take many forms, obviously eggs are a simple and easy breakfast protein food.
"There are some really great protein milks and yoghurts available as well, you can incorporate legumes and tofu for those people who are vegetarian.
"Normally we have the least amount of protein at breakfast, about 11g, and we should be aiming for about 25g."
Mrs Wolter said after a couple of weeks on the diet, which provides participants with recipe ideas, shopping lists and exercise regimens, she didn't have cravings for sugary or high fat foods.
"I never imagined I lose anywhere near what I have," she said.
"I did split it into very small goals at a time ... but I never imagined I'd be able to lose as much as I did.
"The huge difference is that it [CSIRO diet] is backed by science ... so it's not a fad. It's just really simple easy meals, easy recipes, easy normal food."
Speaking of the diet, Mrs Wolter said the journey "wasn't easy" and that shedding the weight came down to mindset.
"The diet makes sticking to it easy because the meals and the food is so simple and easy to follow that if you've got your head in it, does make it simple," she said.
Mrs Wolter, who is now a face of the CSIRO Total Wellbeing diet, said her life has now "completely changed" since the weight loss.
"Before losing the weight, I didn't do any exercise and was more the person sitting back watching rather than participating," she explained.
"Now exercise is my life ... obviously to begin with I could only really do walking, and after I'd lost about 20kg I thought I'm going to have to do something more. So I joined a gym and started with a personal trainer and now that is my life.
"Now, most people who didn't know me before I lost the weight actually can't believe that I was as big as I was. When I show them photos, they say 'it doesn't even look like you'."