Professor Deborah Cobb-Clark, director of the Melbourne Institute of Applied Economic and Social Research, also found people who said they believed their life can be changed by their own actions ate healthier food, exercised more, smoked less and avoided binge drinking.
"Our research shows a direct link between the type of personality a person has and a healthy lifestyle," Cobb-Clark said in a statement. "The main policy response to the obesity epidemic has been the provision of better information, but information alone is insufficient to change people's eating habits. Understanding the psychological underpinning of a person's eating patterns and exercise habits is central to understanding obesity."
The study also found men and women hold different views on the benefits of a healthy lifestyle.
Men wanted physical results from their healthy choices, while women were more receptive to the everyday enjoyment of leading a healthy lifestyle, Cobb-Clark said.
"What works well for women may not work well for men," Cobb-Clark said. "Gender specific policy initiatives which respond to these objectives may be particularly helpful in promoting healthy lifestyles."