Dietitian and health communicator Cris Guerra has analysed the weekly menus in detail to see what truth lies behind the complaints. "On paper, everything is served: vegetables, pulses, fish, meat, eggs and fruit, but on closer inspection we find some very basic errors," she says.

The first of these is a "drastic calorie imbalance" from one school day to another. According to Guerra, schools feature menus with fewer than 500 calories and others approaching 900: an excessive variation for children of similar ages. This does not take into account the amount that actually ends up on their plates.

Added to this are small day-to-day details that reduce nutritional quality, such as the routine use of white bread or bread containing only 50 per cent wholemeal flour, as well as the inclusion of sweetened yoghurts instead of the natural variety.

Guerra highlights the lack of variety in the way food is prepared. Although vegetables are served every day, they tend to be served in the same way time and time again (as a purée or in a salad) while roasted, baked or stir-fried options are overlooked.

"For a child, changes in texture and flavour are very important," Guerra states. She concludes that "a healthy diet for children is not just about adding up nutrients on paper, it has to be appetising, varied and, above all, sufficient".

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