"People feel they have lived with deprivation and they feel they have to watch their weight and count calories," she says.
"It's all about what we can have.
"I went from being a mad runner, running every single day, burning lots and lots of calories, to teaching tai chi and not running. My eating remained the same but my clothes got looser.
"I was noticing that more and more [in other people] and that led me to go back to my text books."
The resulting book is out on Monday.
Stop dieting, start nourishing
"In a world obsessed with calorie counting, we find ourselves instead watching the waistlines of the Western world continually increasing. What if the foundation nutritional philosophy that the calorie equation is the sole determinant of weight loss is completely outdated and in many cases wrong?
"The concept behind this is to stop dieting and to start nourishing. The idea our body shape and size is down to how we eat and move, that whole equation . . . it's time for an update. There are so many factors."
These factors include email. Yes, you read right, email.
Nourishment, as Dr Libby promotes rather than a straight-out diet, involves learning about stress hormones and how to reduce these to help you manage your weight.
"People have a love-hate relationship with them. They never feel they get on top of them.
When we perceive there aren't enough hours in the day that lets our body know to make stress hormones and they have a significant impact on metabolism and whether we use glucose or fat as fuel."
There are no calorie limits and no prescribed amounts of exercise.
"It's awesome when you see the lights go on, to see it doesn't have to be a constant state of eating like a bird and running themselves ragged. There's a lot of freedom. That's a big part of it.
"When we're happy that has a big impact on our work and how we relate to people. Diet, as in the way we eat, has a big influence.
"When it comes to food, nature has got it right. Human intervention can get it wrong. People aren't great at eating less of something. If it were that simple they would already do it."
Top tips
Her top tips are to eat more green vegetables and to eat more fat, especially as the fat will help curb sugar cravings.
"I've seen it happen with thousands of people - eating whole foods and increasing dietary fat. I eat real foods and I don't ever feel like I am missing out.
"A lot more people are opening up to this."
Friday's seminar isn't only for those who have weight to lose - it's open to everyone who wants to learn more about nourishing your body.
The seminar is 90 minutes and there will be questions and answers at the end.
"I love that, that's why I do what I do - to help people. I always stay back at the end to chat to people."
¦ The Road to Sustainable Weight Loss with Dr Libby Weaver is at Rydges Hotel, Fenton St on Friday at 7pm. Visit www.drlibby.com for more information.