The labels show percentages of guideline daily amounts (GDA) of sugar, salt, fat and calories in each serving. Other firms use red, amber and green labels - where green is good and red warns not to consume too much - approved by the Food Standards Agency. But the 21 firms and retailers using the GDA system say people will not buy products with red labels on them. The GDA campaign - supported by a coalition of the UK's biggest food and drink manufacturers as well as supermarkets Tesco, Somerfield and Morrison - begins on Monday with TV and print adverts.
Members of the GDA group say consumers will find the percentages of GDAs easier to understand than the FSA's "traffic light" system. GDA campaign director Jane Holdsworth said the new labelling system was about "lifestyle" choices. "We have made it simple to compare what's inside thousands of everyday foods so you can choose what best suits your diet," she said. And Tesco said its GDA labelling had already changed the buying behaviour of its shoppers.
Tesco spokesman Jonathan Church told BBC Radio 4's Today programme: "Our sales data shows customers are categories." More than 5,000 products already carried GDA labelling and this would be extended to every Tesco-owned food item within the next few months, he said. Mr Church denied the supermarket was trying to safeguard sales at the expense of customers' health, saying fat and salt content in some products had been lowered as a result of GDA labelling.
But supporters of the FSA's traffic light system - used by firms including Sainsbury's, Waitrose , the Co-Op, Marks and Spencer and Asda - say the GDA system is flawed because many adults do not understand percentages. The FSA says its research shows traffic light labels are easier to understand. "Some consumers do like the extra information that GDAs provide," it said in a statement. "However, without a traffic light colour code our research showed that shoppers can't always interpret the information quickly and often find percentages difficult to understand and use." If traffic light colours were added to products with GDA labels this would "reduce the confusion in the marketplace", it added. Diabetes UK also gave their backing to the traffic light system, saying it was the "quickest and easiest" way for consumers to know what their food contained. "If manufacturers choose to produce their own labelling guidance, it will only serve to confuse shoppers," said chief executive Douglas Smallwood. "Voluntary food labelling will only work if manufacturers look at it from the view of the consumer, rather than suiting themselves."