More than 70 leading public health specialists are urging the government to implement a tax on sugary drinks to tackle New Zealand's high rates of childhood obesity.
The specialists, who are from universities around the country, have signed an open letter to Cabinet asking for obesity prevention measures to be strengthened.
A recent report published in The Lancet showed New Zealand had one of the highest numbers of overweight people in the world.
The research revealed nearly 20 percent of the world's obese adults - 118 million - live in New Zealand and five other high-income English-speaking countries: Australia, Canada, the Republic of Ireland, Britain and the US.
The researchers' open letter described the strategies presented last year by the government to fight obesity as "soft".
They said they wanted a 20 percent excise tax on sugary drinks, which they expected would raise between $30 and 40 million.
One of the signatories, Professor Boyd Swinburn of Auckland University, said current government policies were not enough to change the trend.
"New evidence has come to light, there's new international movement, particularly with the UK taking up sugary taxes, and there's a wave of public support for it," he said.
"I really would like them to reassess their position."
Public policy think tank New Zealand Initiative, however, dismissed the idea, with executive director Oliver Hartwich saying better education campaigns would be more effective.
There was no evidence a sugar tax would work, he said.
"We shouldn't just shoot from the hip and we shouldn't just introduce something where we can't be sure how it's going to work.
"We need a very careful debate. We need a conversation that includes the industry, and basically involves the industry in finding solutions."
Health Minister Jonathan Coleman has said a tax on sugar is not being considered here.
By 2025, 17 percent of men and 21 percent of women in the world would be obese, the report in The Lancet said.