New research shows that food taxes and subsidies could improve diets and reduce deaths in Aotearoa, particularly among Māori.

The study, by Auckland and Otago universities, in collaboration with Oxford University, was funded by the Health Research Council of New Zealand.

It shows that by combining taxes on food with high levels of salt and saturated fats, with a subsidy on fruit and veges, about 2400 deaths could be prevented each year in New Zealand.

Professor Cliona Ni Mhurchu, from Auckland University's National Institute for Health Innovation, said such a scheme would assist both Māori and those on low incomes.

"They would benefit more than other New Zealanders, so that is quite different to other health interventions where Māori and Pacific people and low income New Zealanders often benefit less than others."

Professor Ni Mhurchu said obesity and diseases like diabetes were having a hugh effect on the health of New Zealanders.

The research shows that a 20 percent subsidy on fruit and vegetables could prevent or postpone about 560 deaths each year, while a 20 percent tax on major dietary sources of saturated fat could prevent or postpone 1500 deaths.

The same tax on major sources of dietary salt would see about 2,000 deaths prevented.

Professor Ni Mhurchu said the effects of those economic policies were tested in a computer macro-stimulation model based on household food expenditure, price changes, population mortality rates and known links between diet and disease risk factors.

"We needed to know if there would be compensatory purchasing of non-targeted food items and impacts on different socio-economic groups." she said.

Professor Ni Mhurchu said relative to other strategies to prevent obesity and diet-related disease, health-related food taxes and subsidies were likely to be highly cost effective.

She said the evidence to date suggests that targeted food pricing policies could be an effective component of a multi-faceted strategy to tackle New Zealand's high burden of diet-related disease.