Many of the world's 25 biggest food firms only pay lip service to their duty to help fight the global diet crisis, a report on the issue says.
The report attempted to audit food firms' commitments to good health
It found that the response of most companies to World Health Organisation guidelines on fighting obesity, cancer and heart disease was "lukewarm".
Most firms appeared not to care "a jot", the report by London's City University suggested.
A spokesman said the UK food industry took its responsibilities seriously.
The report's authors said the WHO guidelines had placed new demands on food firms, such as promoting healthy diets, improving products' nutritional quality and practising responsible marketing.
Measuring their performance against these, the report found that retailers who presented themselves as the consumer's friend in fact came out as the worst performers.
Manufacturers who have been under attack for selling fatty, salty and sugary foods showed the most activity to deal with problems.
The authors said: "The findings of this report suggest that the world's food companies are not yet fully engaged with the seriousness and urgency of this transformation.
"Companies should be wary about doing the minimum or presenting a few hurried initiatives in self-promotional terms.
"A lukewarm response from food companies to the enormity of the public health evidence amassed by the WHO and researchers risks engendering some cynicism."
The team said the cost of change could not be used as an excuse - as even the smallest firm studied had a turnover five times the WHO's annual budget.
The research team studied the annual reports, accounts and websites of the top 10 food manufacturers, top 10 food retailers and top five food services firms - three food firms and two contract caterers.
They found that even though 23 out of 25 firms stated aims on corporate social responsibilities, less than half made a reference to health in these.
Just 11 out of 25 had policy statements on obesity or children's food, or had a commitment on having a healthier range of products.
Sugar and salt
And only four firms had any policies on the way they advertised - these were Cadbury Schweppes, Danone, Nestle and Unilever.
On the three critical nutrients for health, only 10 reported action on reducing salt, five on sugar and four on fats.
McDonald's, which has been a high profile firm in the debate on diet and health reported no commitments other than on portion size, the report said.
Professor Tim Lang, who led the research, said he was surprised by the findings.
He said: "Food firms spend a lot of time saying they are the consumer's friends.
"Poll after poll say people wanted to do the right thing for their health and their children.
"These are sophisticated, very powerful companies. I thought they would see the benefits of a positive health profile."
He added: "I was really concerned that so many companies felt they didn't even had to pretend."
A spokesman for the Food and Drink Federation (FDF) which represents UK firms said: "If the report's authors want the food and drink manufacturing industry to take more action on food and health, they are pushing at an open door."
He said the group's food and health manifesto clearly demonstrated the industry's commitment to tackling problems surrounding food and health.
He added: "FDF's Food and Health Manifesto includes pledges to reduce levels of salt, sugar and fat in foods and promote healthy lifestyles to both the general public and companies own employees."