By Wendy Tuohy
Maddison Dass grew up in Melbourne’s north, across the road from a park with a large lake, in a suburb with a walking path to the city, and a wide variety of fresh food outlets and options.
“We used to take our dogs to the dog park all the time, but in the last two years we really haven’t done it,” says the new mother to days-old daughter, Juliette.
Maddison Dass with days-old daughter Juliette.Credit: Chris Hopkins
What changed was that Dass and her husband Jacob moved from the north to Sydenham, in Melbourne’s west, where “it’s like living in a whole different world … a different way of life”.
“Even access to chemists or shopping centres – we’ve got Watergardens but not really anything else. You have to drive to find anywhere.”
Early in her pregnancy with Juliette, Dass was diagnosed with type 2 diabetes, and received health support at Western Health’s Diamond (Diabetes, Maternal Obesity, Nutrition and Diet) Clinic for mothers-to-be.
Melbourne is famously liveable, but a close look at the health of mothers and babies across 235 of its postcodes has revealed how many suburbs lack the liveability to help residents avoid overweight and obesity – from birth.
University of Melbourne research pointed to higher chances of weight-related health issues for mothers and babies in some areas – and their health is considered the best gauge of an area’s general health.
Mothers in swaths of greater Melbourne are far more likely to experience overweight and obesity in pregnancy, get gestational diabetes and have babies “large for gestational age” due to suburban features beyond their control.
These features include lower socioeconomic status, the “walkability” and access to green space in the area, as well as fewer fresh food stores and more fast food outlets.
Postcodes around the CBD and bayside, and inner northern and eastern suburbs, enjoyed better maternal and child health than in Melbourne’s growth areas to the west and east, some parts of the Mornington Peninsula and around Western Port Bay. In these areas, women were more likely to be overweight during pregnancy, and their babies were more likely to be born large for their gestational age – weighing at or above the 90th percentile at birth.
Large for age babies are more likely to have metabolic complications in childhood and later in life, which can raise the possibility of other health concerns.
Mother-baby health is “the best indicator of the health of a postcode or suburb”, says Melbourne University epidemiologist and biostatistician Dr Melvin Marzan, because pregnant women and new babies are highly sensitive to their environment and health changes happen to them relatively quickly.
Marzan’s team studied liveability, walkability, fast-food outlet and grocery store densities, as well as neighbourhood amenities by postcode, and overlaid these with records from 31,083 births between 2020 and 2023.
Lockdowns were found to have exacerbated health inequity in wider Melbourne, but the trends his team showed have continued steadily since.
“It’s hard to analyse non-communicable disease with long latency periods, but the conditions we analysed take only months to develop,” said Marzan. “The sad thing about this is, the disparity and variations in the rates of these are not just random, it’s tied up to the characteristics of postcodes.”
The study, published in the Australian and New Zealand Journal of Obstetrics and Gynaecology found areas with more residents born overseas had lower prevalence of maternal overweight and large for gestational age babies.
But they had higher prevalence of gestational diabetes, suggesting migrants may have healthier pre-pregnancy BMIs due to cultural dietary practices, but may be genetically predisposed to pregnancy diabetes or lack access to early pregnancy care.
The overlap between high volume of fast food outlets compared with grocery stores, and increased rates of overweight and larger babies, was so clear that Deakin University public health and planning expert Dr Cindy Needham said the study was more evidence councils should have powers to reject applications for added fast food outlets, based on community health concerns.
Needham studied food retail environments in greater Melbourne, and how they vary between geographic and socioeconomic areas, in developing the Food Retail Outlet Monitoring Tool, an interactive showing food outlet distribution across Victoria.
“At one point we found nine unhealthy food outlets to every one healthy outlet in the growth areas,” Needham said.
“If you have to walk past nine doughnuts at 20¢ each to buy a bag of carrots for $10 ... if we don’t flip that ratio we’re putting people in a position where the healthy choice isn’t the easy choice.”
The research found the built environment of postcodes were “significant determinants” on mother-baby health, independent of the area’s socioeconomic status.
Needham, co-chair of the group Local Governments Creating Healthy Food Environments, which had its first symposium on March 17 and wants new planning powers for councils, said health considerations must be incorporated into planning laws, and Marzan’s research was more evidence this change was vital.
“Research like what’s being published here [Marzan’s], showing this is concrete, the built environment is making us unhealthy, is fantastic; it’s exactly what we need to build the case for policy changes to start protecting people and promoting good health,” Needham said.
“We have to take consideration of health into food planning in retail environments; we need equitable access to good quality, well-priced nutritious food and it needs to be available to everyone as the easy choice.”
Endocrinologist Dr Sarah Price, director of Obstetric Medicine at the Royal Women’s Hospital, said the study illustrated known, underlying health disparities and showed environmental factors make a real difference.
‘There needs to be a cap on fast food outlets when they’re planning new developments – the further you go, the more widespread this problem is.’
Mill Park resident Sarah Marcola
She said babies born large for gestational age who have excess fat tissue are already metabolically different, “and we know that from zero to two, those babies tend to become larger children and have more fat mass, and by school age about half have symptoms of metabolic syndrome”.
These could include borderline blood pressure issues or high glucose levels. “The greatest risk factor for obesity in adulthood is obesity in childhood, and the greatest risk for childhood obesity is being large for gestational age,” Price said.
But with good education, exercise and diet, such children can avoid metabolic complications. “It is not a foregone conclusion; they are probably born with higher risk, but they absolutely can go on to avoid metabolic diseases,” she said.
Money invested in improving the built environments and access to green space in areas where Marzan’s research showed more babies were at risk “would be money well spent”.
Sarah Marcola lives with her family in Mill Park. She believes the high ratio of fast food outlets that do not offer healthy options makes it difficult for many people to stay healthy.Credit: Wayne Taylor
Sarah Marcola, a project officer and mother of two young children in Mill Park, had one baby who was large for gestational age and spent time in neonatal intensive care, but said her family maintained its health by cooking fresh food most of the time.
Her area had large numbers of fast food outlets and many parks were not well maintained, or neglected, and healthy takeaway food was very limited, Marcola said.
“It [overweight in postcodes] boils down to the fast food issue: the lack of healthy options. There needs to be a cap on fast food outlets when they’re planning new developments – the further you go, the more widespread this problem is,” she said.
“We need to be building in parks and councils need to rebuild parks that are absolutely neglected. I took my family to one five minutes from our house, and it’s not safe at all.”
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