Many school children are exposed to shops selling an array of fatty, sugary foods on their way to and from school, a study has found.
The study, the first to look at the issue nationwide, revealed more than 60 per cent of urban schools have a convenience store and a fast food or takeaway outlet within 800m.
The Auckland University research suggested changes could be made to local government and resource management law to allow councils to restrict new unhealthy food outlets near schools, creating a "healthy food zone".
Researchers also urged schools to follow the lead of Rhode Street School in Hamilton, where students appealed to local shops with four out of five agreeing to stop selling lollies and sugary drinks to pupils in uniform before and after school.
Focus on Food dietician Emma McMichael said exposure to unhealthy food on the way to and from school was a big issue.
"Hot chips that are offered next door to the school are very palatable.
"It makes it hard to say to them 'this is what you should be eating' but next door is offering crap that is really tasty."
She said a healthy food zone was a great idea and was the kind of action the Government needed to be taking, but it did not address the existing unhealthy food outlets near schools.
"Changing the food environment and education are two of many things that are going to enable kids to choose the healthy option much easier," Ms McMichael said.
The creation of healthy food zones around schools is a good idea, but not feasible, some Bay principals said.
Greerton Village School was in a unique position of being located in the middle of Greerton Village, surrounded by cafes, restaurants and food outlets, principal Anne Mackintosh said.
Ms Mackintosh said restricting unhealthy food outlets was not "workable".
"I don't know how feasible it would be, there's so many outlets. It would be very difficult to police."
She said education was the way to go, with healthy eating habits encouraged at school and a ban on fizzy drinks and lollies.
Otumoetai College principal Dave Randell said he would love to see a healthy food zone around his school, which was near a fish 'n' chip shop and a dairy which were out of bounds during school hours.
"I just can't see it happening. They are running businesses. They support us by not selling to students during class hours but they have a business to run."
President of Western Bay of Plenty Principals Association and Kaimai School principal Dane Robertson said a healthy food zone could make things better for some kids if they did not have such easy access to cheap, sugary or fatty foods.
Kaimai School had no nearby dairy and Mr Robertson said when the dental van visited the school the dentist said their teeth were in better shape compared to kids' teeth in town.
"I asked her why she thought that was and she said it was because there is no dairy near the school."
Tauranga City Council and Western Bay of Plenty District Council were unable to comment as unhealthy food zones around schools was not an issue that had been dealt with as of yet.
A Western Bay of Plenty District Council spokesman said councils act on legislation and there were no rules regarding the issue in place, but if legislation was to come into play the local authority would respond appropriately.
* First study of its kind in NZ
* Neighbourhoods checked from 2473 schools
* 62 per cent of urban schools had a fast-food shop within 800m
* One school had 85 unhealthy-food outlets per sq km within 800m
* Researchers want law changes to stop unhealthy-food premises near schools