The report by Research Australia, to be released next month, looks at the health impacts of the changing environment.
The CSIRO's Professor Tony Capon says more than three million Australians are obese, and risk shortening their lives by up to 10 years.
He says the layout of today's urban neighbourhoods discourage exercise, and they need to be better planned.
"Ensure that we can do most of our daily business within walking or cycling distance of where we live," he said.
"So we need shops in the local area that we can walk to, safe routes to the local school, pathways to the bus or train stop and there needs to be frequent services of buses and trains." © 2007 Australian Broadcasting Corporation
