Assessment of dietary nutrient intakes: analysed vs calculated values

In this study we compared the nutrient composition of the diet of a nursing home calculated from food composition tables with that obtained from laboratory analysis of cooked mixed dishes. A total of 43 food samples were analysed. Analysed parameters comprised fat, fatty acids, cholesterol, α-tocopherol and eight minerals. We found that calculated values were a good estimation of energy, fat, polyunsaturated fatty acids (PUFA), cholesterol, potassium and phosphorus intakes. In contrast, other parameters showed differences between calculated and analysed values, which ranged from 11% for magnesium intake to 56% for sodium intake (p<0.05). Values obtained from tables tended to underestimate saturated fatty acids, monounsaturated fatty acids, calcium, magnesium and sodium intakes, and overestimate α-tocopherol and iron intakes. Potential sources of error in both methods were studied.