The researchers also found that if a tax of 40 cents per 100g of sugar was applied to sweetened drinks, half of the group wouldn't drink them as often.
"This suggests that a tax on sugar-sweetened beverages may be a well-received and effective public health intervention, which should be considered by policymakers to reduce obesity in Australia," the researchers said in their study, published in the Australian and New Zealand Journal of Public Health on Friday.
In Australia, the biggest consumers of the drinks are teenagers aged 14 to 17, followed by young adults aged between 18 and 30.
Two out of five of the young people surveyed said they'd had a sugary drink the previous day, with soft drinks, fruit juices, energy drinks, sports drinks and flavoured mineral waters the most popular beverages.
The researchers noted that economic modelling had shown that introducing a 40 cent tax on sugary drinks would reduce consumption of the drinks by about 15 per cent, while the government would reap $500 million and the national obesity rate would fall by two per cent.
Sugary drinks are considered by health experts to be major contributors to obesity.
Earlier this week, data from the ABS showed that almost seven-in-10 Australians are either overweight or obese, with the number of 18 to 24 year olds having packed on too many kilos up by nearly a fifth in just three years.
Meanwhile, a team of health economists from Deakin University has found that slapping a tax on sugar-sweetened drinks and alcohol would be two of the best ways for the federal government to tackle Australia's obesity problem.
A Greens-led Senate committee has also recommended a tax on soft drinks and other sweetened beverages, but both Labor and the coalition are opposed to such a move.