Of 70 products tested in a survey not one label was completely correct and only one in 10 contained nutrients in the exact quantities stated. Nearly half had errors of more than 10 per cent - the margin allowed by trading standards officials.
The report published in Which? magazine said laboratory tests found that labels on Marks & Spencer ice cream were found to be 72 per cent out in their measurements of fat levels while Somerfield baked beans contained only half the fibre declared.
Heinz Weight Watchers baked beans contained 72 calories per 100g, not the 56 stated on the pack, it claimed.
Which? managing editor, Charlotte Ganne, said: "Nutritional labelling is not much help to consumers if it is not accurate. The quality of information must be better so shoppers are not misled."