More then two thirds of people in Port Lincoln are considered overweight or obese according to Victoria University's Australian Health Tracker.
Friday, October 11 is World Obesity Day and the latest available Australian Bureau of Statistics data, from 2014/15, shows more than 40 per cent of adults were obese in parts of country South Australia, twice the rate of obesity found in Adelaide's wealthy inner suburbs.
In Port Lincoln the adult obesity rate was 34.4 per cent while 68 per cent were considered either obese or overweight.
Young people considered obese made up 6.4 per cent of the population and 23.4 per cent were either overweight or obese.
The tracker looks at obesity rates in council areas across Australia and rates vary depending on where people live and their wealth.
We have spent too long as a nation expecting individuals to be able to change their behaviour to reduce their weight.Professor Rosemary Calder, Mitchell Institute, Victoria University
In South Australia, Grant, Goyder, Wakefield, Barunga West and Mid Murray council areas have the highest rates of obesity in the state, while less than 20 per cent of the community are obese in the wealthy metropolitan suburbs of Burnside, Adelaide and Unley.
The national obesity rate rose by 27 per cent in the past 10 years to almost a third of Australian adults and well below the national target of 24.6 per cent.
Professor Rosemary Calder from health policy think tank, the Mitchell Institute at Victoria University said action was needed to focus prevention strategies in the most disadvantaged communities.
"We have spent too long as a nation expecting individuals to be able to change their behaviour to reduce their weight," Professor Calder said.
"However, the evidence is very clear that this has little chance of success without a very strong focus on the environmental factors in the places where we live that contribute to poor nutrition and inactivity."
Professor Calder said it was no surprise that Adelaide's wealthy suburbs had the lowest rates of obesity.
"These suburbs are usually green and leafy, with more space dedicated to parks, gardens and recreational facilities.
"They often are well serviced by public transport, bike paths and are relatively close to where people work which enables people to be physically active in their commute to work, rather than rely on the car.
"They have a greater density of shops selling fresh fruit and veg, greater competition promoting lower prices for healthy foods and fewer fast food outlets," Professor Calder said.
"People in our wealthier suburbs tend to have better access to information about healthy diet and the financial means to access healthy food options and enjoyable physical activity."
She said low socio-economic communities were often new suburbs and regional areas that were substantial distances from metropolitan centres and other communities and often did not have physical infrastructure to supports healthy lifestyles.
Professor Calder said policy change was needed at every level government.
"The establishment of a national preventive health taskforce by the federal Health Minister is an essential first step in the right direction.
"It is vitally important that governments at all levels focus on collectively addressing the impact of where we live on our health."
She said places with the highest rates of obesity, also had much higher rates of smoking, inactivity and chronic illness and were largely low-socioeconomic communities, highlighting the impact of poverty on health.
"Local governments are critical to local planning and to creation of healthy and active spaces for their residents, but their ability is often dependent on state government policies and hampered by lack of funding and regulatory power," she said.