A New Zealand mum who self-published a book detailing how she shed 20kg in nine months by just slashing sugar from her diet has secured a transtasman publishing deal.

Amanda Tiffen wrote A Life Less Sugar: How I lost 20kg by reducing my sugar intake after her amazing weight-loss programme.

Using a home printer she ran off copies before it was picked up by nationwide books retailer Paper Plus and went on to sell thousands of copies.

Tiffen, 43, then teamed up with close friend Leigh Brown to launch a cookbook featuring 35 low-sugar recipes that also proved a major hit.

The Herald highlighted Tiffen's story in August 2016.

Publishing powerhouse Harper Collins then contacted the Christchurch-mother-of-two, with a proposal to work together.

Now, A Life Less Sugar has been given the glossy professional treatment and is available for sale in both New Zealand and Australia.

"I'm really proud of it," Tiffen said.

"It's quite amazing that it's been achieved, the book is quite amazing. The amount of people that we can help in Australia is hard to comprehend."

The 272-page "part memoir, part diet and recipe book" compiles both of Tiffen's earlier attempts while updates with new recipes and information.

It tells how Tiffen had always struggled to keep her weight in check.

She tried weight loss programmes, the gym, but nothing kept the kilos off.

But four years, she saw a documentary on the perils of sugar which struck a chord.

Afterwards, a quick survey of her cupboards and fridge discovered that most of what she ate, and thought to be healthy - muesli bars, fruit muffins, sandwiches, stir fry sauces, "low fat" packaged food, fruits - were in fact jam-packed with sugar.

"It was a very big surprise," she said.

Tiffen slowly reduced her estimated daily consumption of 30 teaspoons of sugar to just six.

She increased vegetables, protein and meat, while cutting carbohydrates.

Over nine months, she lost a staggering 20kg "with absolute ease".

Amazed with the results, friends and family followed suit, with similar success.

In a frantic fortnight, she wrote her book which is now on sale at most major booksellers on both sides of the Tasman.

"I've seen it on the shelves at the Warehouse, it's so exciting. I almost want to stand there and see if anyone notices and say, 'That's my book!'" she said.

"I don't know just how far this is going to go and how many more people we can help but it's really exciting."