The Prime Minister's chief science adviser says it is "silly" to rule out sugar and fat taxes to tackle the obesity epidemic.
But that's essentially what the Government has done, with Health Minister Jonathan Coleman last month saying there were no plans for any kind of regulation, and Prime Minister John Key claiming there was nothing wrong with eating junk food, "as long you just don't do it every day".
Appearing on the Paul Henry programme this morning, Sir Peter Gluckman – also co-chair of the World Health Organisation's [WHO] commission on ending child obesity – said with 1.2 billion Kiwis now obese, there are "a whole lot of things that need to happen". They include education, food labelling and perhaps even taxes.
"The issue around these taxes is, how much tax would you have to put in to change behaviour? I think they're a really important signal, and it does look from the preliminary evidence from Mexico that taxes on sugary beverages do reduce consumption," he explained.
"Whether they actually change the obesity rates is not clear yet. The WHO work which I'm leading is currently trying to bring all the data together around these taxes to get a sense of whether they work at all [just] through taxation, or whether it's they're working – if they are working – because of the bigger signal they give to the population."
Sir Peter's comments come the same week researchers from the University of Otago released findings showing the ever-increasing tax on cigarettes was working slowly, but surely, to improve health, reduce inequality and ease the burden on the health system.
"I think it's silly to rule things out until we fully understand the ambit of what could be done," says Sir Peter.
But a major focus should be on food labelling, and making sure people understand what it means, he says.
"The only debate is how, and can we reduce the level on intake of these inappropriate foods, and promote the intake of healthy foods at healthy levels. There's things like portion size, things like education – how many people know what a kilojoule is? How many kilojoules in a calorie?
"Food labelling without education and understanding won't achieve a lot. We need to bring this together, and that's what the Government's working on and what the WHO's working on – trying to come up with a package of things which may well include recommendations around fiscal measures."
Which means taxes – but only as part of a wider strategy.
"If on top of that, signals like a tax on sugary beverages help, then they're really important things to do. But countries have only been introducing these relatively recently, there's increasing interest in doing it, and I think we should just wait until the evidence is clear.
"It's hard to believe that a small tax on sugary beverages would fundamentally change behaviour."