The figures, presented at a conference organized by the Australian Cancer Council, showed that 46% of boys were regular consumers of fast food compared with 34% of girls, while 28% regularly drank sugary drinks compared with 14% of girls.
This meant that boys were more likely to be obese despite doing more physical activity than their female peers, said the report.
Boys also ‘outperformed’ girls in terms of being more easily influenced by advertising – 54% had bought a new food or drink after having seen an advert for it while nearly 40% had gone to a particular fast food outlet because of a special offer.
Nearly double the number of boys than girls had bought a product because it had a celebrity endorsement from a movie or sports player.
Cancer Council chairperson, Kathy Chapman, said the data highlighted the urgent need for measures to protect children, and especially boys, from the power of marketing: "A barrage of increasingly sophisticated junk food marketing is undermining teenage boys’ longer-term health.
“Fast food companies invest tens of millions of dollars in advertising during programs watched by teenagers because mass-media advertising works."
CEO of Australia's National Heart Foundation Mary Barry said: "Government investment in public education to encourage healthier eating is a fraction of the 'pester power' money food companies pour into influencing teenagers’ food choices."
But the link between advertising and childhood obesity has been disputed by some.
A 2009 report by the UK's Department of Education said: “Expert opinion is divided on this issue. Most experts agree that advertising does have some impact, but the evidence is that the impact is very small.
"...Food choice is only one factor in obesity; and other factors – such as the availability and price of food, the influence of parents, patterns of physical activity, and the lack of access to outdoor play areas – play a much greater role.
"Focusing attention on television advertising may lead to a neglect of these other, more important factors.”
Restrict adverts everywhere
While the Children’s Health Campaign is calling for a 9pm watershed on junk food adverts to reduce companies' marketing sway over children, its 2013 report Through the Looking Glass highlighted how companies were increasingly turning to online advertising, social media and advergames to plug their products - taking advantage of legal loopholes over online advertising as well as children's increasingly computer-savviness.
The report also criticised the UK's Advertising Standards Agency (ASA) for failing to act to protect children.
But Matt Wilson of the ASA told FoodNavigator: "I believe the debate has moved on since the 2013 report by the Children’s Food Campaign. The issue of food and drink advertising to children is an important one and a key focus of our policy and enforcement work.
"We understand that some health campaigners believe advertising of food and drink to children is harmful and question why we don’t introduce tougher rules or an outright ban (...) It’s our job as the advertising regulator to make sure that we maintain a balanced approach, taking into account competing views but all the while making sure the rules are based on evidence.
In January this year the Netherlands banned all forms of food advertising to children under 13 years of age, with the exception of certain foods that meet a certain nutritional criteria for saturated fat, sugar and salt content and calorie count.
A 2006 survey by UK organisation Compass found that 70% of three year-olds recognised the McDonald’s logo while only half knew their own surname.