There are calls to limit access to fast food outlets and dairies around schools to help combat the obesity epidemic.
A new study reveals 60 percent of urban schools have a convenience store and a fast food or takeaway outlet within 800 metres.
University of Auckland researchers measured the proximity and density of fast food, takeaway and convenience outlets around New Zealand schools in 2014.
One school in Auckland's CBD was found to have 85 unhealthy food outlets within one kilometre.
It's not just Auckland, but schools in all urban areas says lead researcher Dr Stefanie Vandevijvere from the University of Auckland's School of Population Health.
"Among rural schools, representing about one-third of schools in New Zealand, access to unhealthy food outlets does not seem to be a problem, as the median road distance to the closest unhealthy food outlet is more than 10 kilometres," says Dr Vandevijvere.
The study, published today in the American Journal of Preventative Medicine, showed that access to unhealthy foods is greater for the most socioeconomically deprived schools.
Dr Vandevijvere says there should be ways to reduce children's exposure to unhealthy foods before and after school.
"As a way of protecting children from exposure to unhealthy food sources and obesity, creating healthy food zones around schools may be an important policy lever, but has not been widely implemented yet."
Dr Vandevijvere would like to changes to the Resource Management Act (1991) and the Local Government Act, so councils could restrict new food outlets in school neighbourhoods.
Clinical director at Auckland Regional Public Health Service Dr Julia Peters agrees.
"That kind of saturation of calorie-dense, really poor quality food is sending a signal to people that that's normal and actually it's far from normal," says Dr Peters.
She says our food environment is driving the obesity epidemic.
"The problem we've got at the moment is that being able to get fast food straight after school is undermining what schools are trying to do and potentially what families are trying to do."
But Environment Minister Nick Smith says the Resource Management Act is about protecting the environment, and it would be a big stretch to also have it responsible for regulating healthy food.
"Councils have discretion about allocation of commercial activities, but zoning rarely differentiates between different types of commercial activity, whether they be dairies, cafes or fast food outlets," says Dr Smith.
"The Government is intent with its resource management reforms to make the regime less bureaucratic. This proposal goes in the opposite direction and would have council planning committees and the Environment Court regulating the type of food that could be sold, which would not be practical."
Dr Peters says there's no silver bullet but believes restricting unhealthy food outlets near schools would help children make healthier choices.