Over the last three decades, the average Australian man has gained eight kilograms in weight.
The average woman has added 6 kilos.
A study published in the scientific journal Nature examined data from more than 112 million people from 200 countries and territories.
Bill Stavreski is the Heart Foundation's General Manager of heart health, and says those weight gains are significant.
The study also found a higher proportion of adults in major Australian cities were overweight compared to outer regional and rural areas.
From 2011-12 to 2017-18, there has been a 25 per cent increase in city dwellers who are overweight compared to only a five per cent increase for those in outer regional and rural areas.
The report's authors say urban areas "provide a wealth of opportunities for better nutrition, more physical exercise and recreation".
A report issued in April revealed that efforts being made by state and territory governments to tackle obesity vary significantly.
At the time, Obesity Policy Coalition Executive Manager Jane Martin told SBS News there has been commitment demonstrated at a state and federal level, but Australia as a nation is failing to offer consistent policy-making against obesity.
Speaking to SBS in March, Nicole Turner from the Collection for Action on Obesity says that so far, government policy - and spending - on obesity has failed.