United Nations food and health authorities drew back from a full-scale confrontation with the world's sugar industry on Wednesday by saying their latest recommendations on sugar consumption were guidelines rather than standards requiring regulation.

The UN Food and Agriculture Organisation and World Health Organisation were reacting to sugar industry complaints about an FAO-WHO report that suggests people wanting to avoid chronic diseases should limit daily consumption of free sugars to less than 10 per cent of total energy intake.

Free sugars include sugars added to foodstuffs by manufacturers, cooks or consumers, as well as sugars naturally present in fruit juices, honey and syrups.

The UN recommendations have outraged US sugar producers, who have indicated they may lobby the Bush administration and Congress to link US funding for the WHO to changes in research methods at the UN agency. The US supplies 22 per cent of the WHO's budget.

"We are asking members of Congress, the White House office of management and budget and the general public to express concern when their taxpayers' dollars are being misspent on misguided reports that are not supported by the preponderance of science," said Andrew Briscoe, president of the Sugar Association.

Mr Briscoe criticised the report for not being subject to peer review and called on the WHO to assess the impact of its recommendations on sugar-producing developing countries.

He added: "This report has not been approved by the WHO executive board or the WHO world assembly."

Jacques Diouf, the FAO's director-general, said the report's recommendations on sugar consumption had been taken out of context. "I believe the experts themselves would agree that this recommendation is not meant to be a precise quantitative limit derived from scientific experiments, but the best compromise based on current knowledge," he said.

"In any case, the recommendation to limit the intake of free sugars is meant to be a desirable population nutrition goal, not a standard to be regulated. Certainly, research will have to continue in all the areas addressed in the report," he told a conference in Rome.

However, Shiriki Kumanyika, a professor at the University of Pennsylvania's School of Medicine, pointed out that an earlier UN report, issued in 1990, had made the same 10 per cent recommendation. Prof Kumanyika, who helped produce the latest UN report, said at least 20 governments around the world recommended a 10 per cent limit on sugar intake. "I don't see any way that we can be said to be misconstruing the evidence," she said.

Gro Harlem Brundtland, the WHO's director-general, added: "The solidity of the work done by the experts is well founded and makes these kinds of criticisms [by the sugar industry] unreasonable."

The report, entitled "Diet, Nutrition and the Prevention of Chronic Diseases", states that cardiovascular diseases, diabetes, various forms of cancer, obesity, osteoporosis and dental disease contributed almost 60 per cent of the 56.5m total reported deaths in the world in 2001, and 46 per cent of the global burden of disease. Throughout Asia, Latin America and parts of Africa, obesity is becoming a serious problem, the report says.

It recommends a diet in which carbohydrates provide 55 to 75 per cent of a person's energy needs. Fat should make up 15 to 30 per cent and saturated fats less than 10 per cent. A healthy person should eat at least 400g of fruit and vegetables a day, and devote one hour a day to moderate physical activity, such as walking, on most days of the week.