Health experts say governments have failed to tackle Australia's "tsunami" of chronic disease and soaring rates of obesity, fearing the problem will only get worse unless the the healthy food star rating system is reinstated and junk food promotion is restricted.

In the first profile of Australia's eating habits available in 15 years, the Australian Health Survey of 12,000 people found we are eating 30 per cent less fruit and vegetables than 15 years ago, with one in four adults eating no vegetables on an average day and only 7 per cent eating the daily recommended five servings.

Professor of health policy at Curtin University Mike Daube said "incredibly low" vegetable consumption reveals that fast food has eclipsed vegetables as a dietary staple.

"It is a major concern," he said. "Unless governments take the way we eat seriously then there will be dire implications for health budgets and the cost of diabetes will blow out. The results are a triumph for the mass marketing of junk food."

Australians eat about three kilograms of food and drink each day, with just over one-third of daily energy from foods high in saturated fat and sugar such as cake, biscuits, alcohol, soft drink and chips.

Professor Daube said most people would be "horrified" to realise much of their energy intake is from food that is essentially useless.

But the survey results also show that, despite Australians weighing about four kilograms more than 20 years ago, overall we are eating less.

Men are consuming about 9600 kilojules each day – 1400 kJ less than 15 years ago – and women's average energy intake has dropped 1 per cent to 7400 kJ each day. The survey also shows people are eating about 226 grams of carbohydrates daily, the equivalent of about 12-14 pieces of bread, which is about 12 per cent less than 15 years ago.

National spokeswoman for the Heart Foundation Kellie-Ann Jolly said the "dismal" daily intake of vegetables combined with fatty food diets means many people are "unaware" of what they are eating.

"We are seeing a drop in physical activity combined with eating far too much saturated fat," she said. "Food like pastries and cake, which were once occasional, have become daily."

Jane Martin, executive manager of the Obesity Policy Coalition, said the survey results highlight how pervasive unhealthy eating has become.

"It's really important we have a healthy food star rating system," she said. "Foods that look largely the same can have very different nutritional profiles. It would encourage companies to reformulate and let consumers know which food is the healthiest."

Ms Martin said the "huge amounts" of highly processed foods eaten each day show the "marketing success of McDonalds, Hungry Jacks and KFC, which are targeted to teenagers".

The results also reveal that more than 2.3 million adults reported being on a diet, almost one in three people aged over 19 drank alcohol on an average day and almost 30 per cent take at least one dietary supplement such as vitamins, minerals and herbs daily.

Almost 4 million people reported avoiding a food type due to allergy, with cow's milk and gluten the most common intolerances.

But Professor Daube said many Australians "still don't have a good understanding" of what amounts to healthy nutrition.

"There is an increasing responsibility of supermarket chains to promote healthy food. The onus isn't on teenagers – it's with governments, parents and retail food outlets."

Correction: The original version of this story said that 226 grams of carbohydrates daily is the equivalent of about four pieces of bread.