In repealing the regulation brought in by Labour, it said instead schools were required "to promote healthy food and drink" - something the Heart Foundation says only 60 per cent are currently doing.
The Horizon Research Poll on healthy food was carried out for the University of Auckland and funded by the Heart Foundation and the Cancer Society of Auckland.
Only 22 per cent of respondents thought the Government should not intervene on both food in schools and fundraising.
"The message is clear - the New Zealand public wants strong government leadership to ensure that what is served in the school canteen matches what is taught in the curriculum about healthy eating," said Professor Boyd Swinburn, who specialises in population nutrition at the University of Auckland.
He said it seemed the public thought the idea was a "no-brainer" and it made sense to have schools as role models as part of an approach aimed at reducing childhood obesity.
"They create a kind of 'lighthouse effect' for healthy eating which shines far beyond the school gates."
New Zealand has the third highest rate of adult obesity in the OECD behind Mexico and the United States. At least 10 per cent of pupils are obese and more than 20 per cent are overweight.
Professor Swinburn said while many New Zealand schools had programmes to promote healthy food to their school community, statistics from the Heart Foundation showed 40 per cent were not engaged in any voluntary healthy food scheme.
New Zealand Principals' Federation president Denise Torrey said that figure was disappointing, but policies aimed at schools could only go so far.
"We can educate students. But obesity doesn't start at school. Families - and legislators - have to do their bit as well," she said. "We are happy to do our part, but schools are not here to solve all social problems. When it comes to food, we don't have any choice about what parents buy. Are they going to legislate around that as well?"
Labour health spokeswoman Annette King said she would now expect the Government to bring back tuck shop regulation.
"It's horrifying to New Zealanders that we are now considered one of the fattest nations in the world," she said.
"We have wasted seven years, when we could have been doing something about it, for purely political reasons, because apparently saying what kids could eat was being a 'nanny state'. I now look forward to seeing what the minister will do."
Health minister Jonathan Coleman said New Zealand was not unique in its battle with obesity and there was no single solution.
It already had several actions under way, including including KiwiSport, green prescriptions, and fruit in schools.
"I have officials from Health and Sport looking at additional measures," Dr Coleman said. "No decisions have been made on what shape or form any interventions will take."
Students learn A to Z of healthy eating
The children at Rhode Street School, Hamilton, know where food comes from - they have grown vegetables, read nutrition labels, and have even killed and plucked their own chooks.
"A few said they were going vegetarian after that," said principal Shane Ngatai.
"But we believe it's important to teach them by doing, not just giving them a poster or whatever."
Rhode Street is involved in the Healthy Heart programme, aimed at teaching children about eating better and promoting physical activity.
For the past 10 years, the school has taken its students, parents and teachers on a journey, growing its own food, cooking in a commercial kitchen, making lunches and snacks and turning the surplus into products for the farmers' market.
Lessons about sugar, salt and portion control go hand-in-hand with food preparation, Mr Ngatai says. There are also lessons for parents, and a points system to make the school waste-free, he says, plus an emphasis on exercise and preventative medicine.
The difference has been in a shift to healthy attitudes and students on task with learning.
"We've seen weight reduction in obese students and fitness levels improving," Mr Ngatai says. "It didn't negatively affect the tuckshop at all. In fact, it strengthened it because our health promotion focused on healthy eating and our students helped us design the changing menus. As a result profits have increased each year."
