The message is loud and clear, yet when it comes to the decisions we make every day about what to put in our mouths and shopping trolleys, it seems not to be getting through.

Research released this week found diet and exercise campaigns are so ineffective at preventing heart disease that they should be abandoned in favour of strict government regulation of salt content in foods and wider medication use.

All the money spent on advice and information has had a ''trivial'' effect when it comes to heart disease, according to the study by Linda Cobiac, a research fellow at the University of Queensland's school of population health.

Healthy lifestyle messages cost state and federal governments $132.9 million in 2008-09, with the amount spent growing more than any other public health area. NSW was behind only Victoria in its spending on health campaigns - $64.5 million in one year. But the statistics seem at odds with all that spending. Cardiovascular disease remains the leading cause of death while the number of overweight and obese adults has doubled over the past two decades, with almost a quarter of the population now obese.

Bruce Neal, a professor at the George Institute for Global Health, says we are living in an environment where even our best intentions are doomed to fail when it comes to healthy eating. That is because the food we eat and what goes into it is already being heavily mandated - not by the government, he says, but by the food industry itself.

''The sort of debate between individual choice and responsibility versus the nanny state is sold to us by the food industry and corporations,'' Professor Neal says.

''There is this strange notion that freedom of industry equals freedom of choice. The reality is different. Big food isn't about nutrition, it's about maximising shareholder profit. And these two things are in deadly conflict.''

It is a conflict that makes it almost impossible for the average consumer, for example trying to avoid salt, to do so, he says. ''It is added to everything, it is invisible, and the food industry is fighting tooth and nail against showing people what is in the food they eat in a quick and easy format. The industry and government like to say what we eat is a matter of individual choice because it takes the pressure of them. But consumers don't have a choice and they need help.''

Neal compares the debate about salt regulation with that of tobacco. In that case the benefits of regulation are accepted by most. ''For tobacco at least we've got past the choice issue and we are now saying, 'It's not your right, and there are things you need to be protected from.' People are yet to put food and alcohol in quite the same category.''

The federal government is targeting lifestyle-related diseases under the National Partnership Agreement on Preventive Health by providing nearly $900 million over six years. The government has been encouraging the food industry to voluntarily make changes to ingredients and food packaging rather than coming down on them with a forceful hand. They are tackling dietary reform through the Food and Health Dialogue, an initiative that has brought the food and health industries together to work with the government.

Neal and his fellow researchers have been closely monitoring the initiative to see how effective it has been. ''I think the Food and Health Dialogue is this toothless, gutless entity moving along at a glacial pace and it is likely to deliver very little to Australians,'' he says.

One of the groups taking part in the dialogue initiative is the Heart Foundation. Its chief executive, Lyn Roberts, agrees food reform is moving slowly in Australia, but adds she was encouraged by the release last month of the National Food Plan green paper, which aims to provide nutritious and affordable food to Australians while also ensuring the food and manufacturing industries remain competitive.

''For the first time we're seeing agriculture, food industry and health interests coming together, and we are now very well placed to make some significant improvements,'' Dr Roberts says. ''We need to make sure our approach places food and public health at the front and centre.''

But the chief executive of the Public Health Association of Australia, Michael Moore, disagrees, and says the National Food Plan has made public health subordinate to the agricultural and manufacturing industries. ''That's the sad part,'' he says.

''Human health should be at the forefront. Governments take into account maintaining successful industries in terms of agriculture, importing, exporting and manufacturing. But the truth is food industry regulation doesn't cost much money or take much time.''

A Coalition government would be unlikely to take a different stance, with the Opposition Leader, Tony Abbott, making his position on food industry regulation clear. He told an International Obesity Conference in 2006: ''We can't have a bureaucrat supervising every family's mealtime. What we need to do is to give people more opportunities to do the right thing by themselves.''

But Moore says industries like tobacco have taught us that reform works best when public awareness campaigns are combined with government legislation. Exercise is not enough. Companies need to be forced to make food packaging easier to understand, he says, with indicators as to how healthy the food is in plain sight rather than hidden on the back in ingredient lists.

Some argue that people never used to be overweight. They moved more, cooked from scratch and did not rely on or have access to so many manufactured foods. But Moore says looking to the past for answers was not the answer.

''We reach for manufactured food because there is less time to cook as we have more people in the workforce now, which is not good or bad but it does mean there is no point looking at where we came from and how we used to be. We have a set of circumstances now and we need to operate within those parameters,'' he said. ''And that means we need governments to react fast. They can see the impact.''