The campaign is being expanded to carry healthy diet messages on prepacked and loose fruit. The first products will be in store by the end of October and immediate focus will be on citrus, mushrooms, potatoes and apples, said business planning manager for produce, Hamish Renton. 'We would expect the information to be carried on 90 per cent of all produce by Christmas,' he added.

Renton said this has already led to a substantial investment. The last year has seen cartoon characters used at point-of-sale as well as literature explaining the healthy diet message. Initial results show increased interest and sales.

Now past what Renton calls the tactical stage, Tesco research has shown that consumers need advice on what constitutes a portion, and this will be available in-store on new colour-coded labels.