[Potassium and sodium content of hospital general diets--comparison of calculated and analytical values].

Our knowledge on the composition of general hospital diets still relates virtually exclusively to calculated values derived from food tables. To find out how relevant these are for the estimation of potassium and sodium contents of the general diet data were chemically analysed and compared to table values. The chemical analysis of daily general diet portions resulted in a mean value of 1.86 g potassium/day in contrast to the calculated mean value of 2.72 g/day. As far as the sodium contents of the general diets are concerned, the picture was reversed (calculated: 3.16 g/day, analysed: 5.20 g/day). These results suggest that only chemical analysis of hospital diets guarantees an adequate supply of potassium and sodium.