Sydney resident Amy Devereux decided to go on a diet to lose weight.
"I saw some photos of myself that I just wasn't looking my best in. It didn't feel good to be the biggest I had been."
After three months on a high-fibre diet, the school teacher lost over 12 kilograms.
She swapped fast food and sweets, for fresh foods and wholegrains in her diet.
But she found it wasn't just her physical appearance that changed - she says gut-friendly recipes improved her general wellbeing and immunity.
She wants to encourage other Australians to give it a try.
"Have I eaten enough vegetables today or have I eaten enough fruit? Just balance - the secret is just balance. So many people ask that question and say 'oh you know, what did you cut out, what did you do, what is the one thing that you changed?' It's not about one thing, it's a holistic approach and I think that's why it's maintainable."
Ms Devereux's experience is backed by new research from the government's science agency, the C-S-I-R-O, which insists Australia's failing gut health needs to be addressed.
With two of every three Australians now classed as overweight or obese, C-S-I-R-O scientist Gilly Hendrie says those are the people most at risk.
"Overweight and obese people are more likely to experience poor gut health symptoms: things like heartburn, abdominal pain and discomfort, bloating, irregular bowel habits, and also they tend to have a poor diet, low in fibre, which can exacerbate some of these symptoms."
Ms Hendrie and her team found half of Australians experience gut health problems, while one in seven experiences them to a distressing degree.
The C-S-I-R-O says the figures come as no surprise, considering 83 per cent of Australians don't get enough fibre in their diet.
Ms Hendrie notes it's not only Australians - it's a trend that's happening around the world.
"Similar with other developed countries such as America such as America and the UK. We all overconsume junk foods and underconsume vegetables and, to some extent, fruit as well."
Nutritionists say fruit, vegetables and wholegrains are the high-fibre foods that can feed the good bacteria in people's digestive system, and improve gut health.
High-protein foods and legumes are also recommended by dieticians.
Simone Austin, from the Dietitians' Association of Australia, says it's also a great way to lose weight.
"By feeding our gut bacteria, we're learning more about how that, the good gut bacteria can send messages to our brain, by producing hormones and proteins, that can help control our appetite."
