In a first-of-its-kind study, Deakin tracked Melbourne’s food retail environment over the past decade, showing residents in some growth suburbs now walk or drive past an average of nine takeaway shops to reach just one healthy food outlet.

The findings also show Melbourne’s 21 per cent population growth between 2008 and 2016 was surpassed by a 35 per cent rise in the number of food outlets across the city.

Leader of the study Cindy Needham, a PhD candidate in the Global Obesity Centre at Deakin’s Institute for Health Transformation, said this was turning Melbourne into an unhealthy ‘food swamp’.

“A food swamp is an area where unhealthy food retail outlets dominate the landscape compared to healthy options, making it challenging for people to maintain healthy diets,” Ms Needham said.

“It’s very challenging to eat a healthy diet when you’re surrounded by unhealthy options, and that is a serious concern if we want to address rapidly increasing overweight and obesity levels.”

The study – published today in the International Journal of Environmental Research and Public Health – is the first to examine the density of food outlets in a large metropolitan city over time, specifically examining variation between Melbourne’s inner, middle, outer, and designated ‘growth’ local government areas.

Outlets were broken into healthy, less healthy and unhealthy categories. Healthy outlets included stores like greengrocers, butchers, supermarkets and salad bars. Less healthy outlets included things like bakeries and delis, while examples of unhealthy outlets included fast-food chains, takeaway shops and convenience stores.

A map of Melbourne's growth areas showing unhealthy to healthy

The data showed that since 2008, the density of fast food chains across Melbourne has almost doubled, with a 92 per cent rise to 2016. The study found Melbourne’s growth areas in Wyndham, Whittlesea, Melton, Hume, Casey and Cardinia were the hardest hit.

“Our data shows those living in growth areas have far fewer healthy options compared to other parts of Melbourne, with the number of fast food and takeaway outlets growing faster than supermarkets in these areas,” Ms Needham said.

“Growth areas have the highest ratio of unhealthy to healthy food outlets. A resident in some of these suburbs has to walk or drive past about nine unhealthy outlets before they find one healthy outlet. This is compared to six unhealthy outlets to every one healthy outlet in inner Melbourne.

“What our study shows is that every other type of food outlet decreases in density as you move away from Melbourne’s CBD, except for fast-food.

“Projections estimate that half the world’s population will be above a healthy weight by 2030. The reality is that we have an obesity epidemic at the same time the availability of food, especially unhealthy food, is rapidly increasing.”

Ms Needham is now working with health promotion foundation VicHealth to examine whether differences in food environments are related to differences in obesity prevalence and dietary choices in these areas.

VicHealth CEO Dr Sandro Deamio said more needed to be done make it easier for families to access and eat fresh, healthy food.

“In Australia children from disadvantaged communities are almost twice as likely to be above a healthy weight than children from wealthier areas,” Dr Demaio said.

“This is absolutely linked to the proliferation of unhealthy food outlets in our outer suburbs and the lack of affordable, healthy options available for families.

“There’s something very wrong with our system when unhealthy food outlets dominate our suburbs. It’s time we stepped up to the plate and protected kids from an industry that puts profits ahead of our kids’ health.”

Dr Demaio said local governments should be empowered to have greater control over their community’s food environments.

“It’s clear we need to increase access to fresh fruit and vegetables in growth areas and make healthy food more accessible and affordable,” he said.

“We also need to closely monitor the changing food retail landscape – we cannot sit by as our least advantaged areas are swamped by increasing numbers of unhealthy food outlets.”