Quantitative use of the Food Guide Pyramid to evaluate dietary intake of college students

Abstract

Objectives: To evaluate the usefulness of the Food Guide Pyramid as a quantitative tool for assessing nutritional adequacy and quality.

Design: One-day food records (n = 2,489) were assigned food group scores (1 through 5) by two systems. System 1 recorded the number of food groups on a given record that included the minimum number of servings suggested by the Food Guide Pyramid. System 2 recorded the number of food groups in the Food Guide Pyramid for which at least one serving was included. The food records were further evaluated by mean adequacy ratio (MAR) for iron, calcium, magnesium, vitamin A, and vitamin B-6 (MAR-5 score) and percentage of energy contributed by fat and sugar. Sensitivity and specificity of the food group scores to predict nutritional inadequacy were determined.

Subjects: College students (n = 2,489) attending introductory nutrition, foods, and health-related courses at a mid-western university.

Statistical analyses: Student's t test, chi2 test, Dunnett's multiple mean comparison test.

Results: A food group score of 5 was given to 11% and 35% of the diet records by systems 1 and 2, respectively; MAR-5 scores of 75 or greater were given to 70% of the records. Only 4% of the diets contained both 30% or less and 10% or less of energy from fat and sugar, respectively. Both scoring systems can be used as a quantitative tool for screening nutritional inadequacy with high sensitivity (correctly classifying nutritionally inadequate diets) but with a moderate to low specificity (correctly classifying nutritionally adequate diets).