Energy and nutrient values from different computerized data bases.

Twenty-four dietary records were analyzed using three computerized nutrient data bases. Differences in mean values were found for 9 of 19 variables evaluated. No one data base consistently yielded highest or lowest values for all nutrients. Mean values appeared to be most consistent among the data bases for energy and the energy-yielding nutrients, calcium, phosphorus, and magnesium. Even when mean values did not differ significantly, values for some individual diets were widely discrepant. Whether comparisons of calculated energy and nutrient values are within or between studies and based on a few or many days of dietary information, values should be recognized as estimates and their limitations and strengths respected.