Governments which put in a tax on sugary drinks would stand to reap hundreds of millions of dollars, cut health spending and result in fewer cases of Type 2 diabetes.
The Queensland University research, published in journal PloS ONE today, suggests a 20 percent tax on sugary drinks would bring in NZ$442 million a year and reduce annual health expenditure by up to $32 million.
Modelling used in the study looked at the effects over the lifetime of adult Australians alive in 2010.
The research predicts the tax would result in:
The study defined a sugar-sweetened drink as non-alcoholic with added sugar, including soft drinks and flavour mineral waters, but excluding fruit juices, fruit drinks, energy drinks, milk-based drinks and cordials.
Researcher Dr Lennert Veerman Veerman says the overall healthcare cost savings would increase over the first two decades, and then plateau around $32 million.
It's estimated the cost of putting in a tax was $30.5 million, but the researchers say the savings on health spending would be more than 14 times that.
Previous studies showed a 20 percent tax, based on product price rather that sugar content, could cut energy consumption by around 10,000kJ per person per year, cut body weight by 0.93kg and save households an average of $18.80.
"Policymakers have cited limited available evidence as a barrier to policy progress in the area of taxes on unhealthy foods, so we expect the detail in our study will be useful to them," Dr Veerman says.
Dr Veerman says Australians in lower socio-economic groups were disproportionately affected by diet-related illnesses and likely to get the biggest benefits as a result of the tax.
Study co-author and Obesity Policy Coalition executive manager Jane Martin says with one in four children and 67 percent of adults now overweight or obese, governments need to take decisive action.
The UK government is already set to introduce a sugar tax on companies according to the volume of sugar-sweetened drinks they produce or distribute.
But the New Zealand Government won't be following their lead, with Health Minister Jonathan Coleman saying it's not something they're "actively considering".