At Britain’s first “salt summit” Melanie Johnson, the Public Health Minister, will tell manufacturers, including Heinz, Cadbury, Nestlé and Kraft, that unless they take action by next February they might have to label their foods “high in salt”.

Evidence of the deadly effects of too much salt has put the food industry under intense pressure to reduce usage by as much as 40 per cent. Processed food contributes about 75 per cent of the salt in people’s diets.

“Salt can be a hidden killer,” Ms Johnson said. “Whereas people are generally aware of the risks of a high sugar or high fat diet, they’re often —unaware of the effect of high salt intake.”

The summit taking place in London is being hosted by the Department of Health and the Food Standards Agency.

According to the department, more than a third of adults suffer from high blood pressure, which is linked to a high salt intake. High blood pressure contributes to about 100,000 deaths a year from heart disease in England and 50,000 a year from strokes.

The department said that salt in beefburgers should be cut by an average of 40 per cent and bread and breakfast cereals by between 20 and 40 per cent. The recommended maximum daily intake for a child aged four to six is 3g a day and for adults 6g a day. The Food Standards Agency has set a target of reducing average salt intakes by 10 per cent, or about 1g a day, by 2005-

06. Ms Johnson said: “If we don’t see progress then action on food labelling could be the answer. I want to see openness and honesty and healthier options, which in turn will open people’s eyes to the risks of a high salt diet.”

Pizzas should, by the end of next year, contain no more than 3g salt per serving or 3.9g for those using cured meat as an ingredient. By then 66 per cent of all ready-made meals should contain no more than 3g salt per serving and no single product more than 5g salt per serving.

All fresh, dried and canned soups should contain no more than 2.5g salt per serving.

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