The stratification of foods on the basis of overall nutritional quality: the overall nutritional quality index.

Purpose: Consumer understanding of nutrition information is key to making dietary choices consistent with guidelines. The development of an objective, science-based, and universally applicable system of nutrition guidance would be of considerable potential value to the public health.

Design: A multidisciplinary expert panel was convened to develop the Overall Nutritional Quality Index (ONQI). Dietary guidelines, existing nutritional scoring systems, and other pertinent scientific literature were reviewed. An algorithm based on the overall nutritional quality of food was developed and subjected to consumer research and validation testing.

Results: The ONQI algorithm incorporates over 30 entries representing both micronutrient and macronutrient properties of foods, as well as weighting coefficients representing epidemiologic associations between nutrients and health outcomes. The basic entry in the algorithm is a weighted trajectory score, which compares nutrient concentration in a food to the recommended concentration of a given nutrient in a healthful diet. In content validity testing, ONQI rankings and expert panel rankings correlated highly (R = .92; p < .001). In regression analysis, aggregated ONQI scores for total diet corresponded well with the Healthy Eating Index (p < .001) in the National Health and Nutrient Examination Survey 2003-2006 cohort (n = 15,900). Consumer research indicated strong appeal to consumers of the ONQI system in general, and the scores on a 1 to 100 scale specifically. A system for acquiring nutrient data, meeting U.S. Food and Drug Administration and U.S. Department of Agriculture standards, has been established so that virtually any food, beverage, meal, or recipe can be scored.

Conclusions: The ONQI is a sophisticated nutrition guidance system developed by a multidisciplinary group independently of all food industry interests with excellent initial performance in both consumer research and validation testing. Combined with a consumer education program, the ONQI has considerable potential to improve dietary patterns, and consequently the public health. Prospective study of effects on dietary patterns and health outcomes is warranted.