The choice of a diet quality indicator to evaluate the nutritional health of populations

Background: The USA and Canada both want to reduce social health inequalities in their population. These two countries have recently begun a process of harmonization of their nutrient recommendations. Objective: To develop a standardized indicator to measure the impact of these recommendations on the health of different social groups in North America. The authors have compared three of the methods currently used for measuring overall diet quality for a population. Design and setting: The three methods, adjusted to the 1990 Canadian nutrition recommendations, were used to analyse the Quebec Nutrition Survey data collected by Sante Quebec in 1990. Results: The authors found that the indicator developed by Kennedy and collaborators works best for analysing the Quebec data. Moreover, it allows comparisons with the USA. Some questions, such as whether or not to add calories from alcohol consumption to the model and whether the indicators should be adjusted to the different cultures and specific population groups remain unanswered. Conclusions: In order to determine the role of nutrition in social health inequalities, it is important to develop standard indicators that are suitable for monitoring the relationship between dietary recommendations and eating habits.