Hospital caterers have come under fire for the second time in a few months, with the publication of a critical report by the Consumers' Association.
According to a survey of 288 hospitals carried out by the association, NHS meal providers are failing to offer a healthy choice of food.
Only one in three hospital menus offered what the association calls "nutrient-dense" options, providing the proteins and minerals essential for recovery. Only half the hospitals used standard recipes for their dishes, which the association says are essential for monitoring proper nutrition.
The report, which appears in the August issue of Which? way to Health magazine, praises hospital caterers for improving the availability of low-fat, high-fibre options.
But it says these options are suitable only for the reasonably fit and healthy, and may delay recovery for those who have undergone surgery or suffered a major illness.
In April, a National Audit Office report on NHS catering recommended hospitals set quality targets, and criticised caterers who expected patients to choose meals up to a week in advance.
Mark Hayman, national secretary of the Hospital Caterers Association (HCA), said many of the criticisms made in both reports were already being addressed.
He said the HCA had been working with the Department of Health to produce nutritional guidelines for hospital caterers, which will be available at the end of September.
In addition, it is working with the NHS Management Executive to draw up performance indicators to compare standards between caterers. Mr Hayman said these are due to be implemented by next April.