Background and aims: Since dietary patterns can influence levels of major risk factors for chronic disease, various indexes or scores of overall diet quality have been proposed and related to risk factors for disease. The Mediterranean Adequacy Index (MAI) was developed to simply assess how close a diet is to the Healthy Reference National Mediterranean Diet (HRNMD), a healthful diet in which Mediterranean food patterns are inversely correlated with prevalence of risk factors for chronic disease. This report describes further evidence of MAI values for diets of population groups from different countries.

Methods and results: MAI is obtained by dividing the food group intakes typical of a healthy reference Mediterranean diet, expressed in g/day, by the food group intakes not characteristic of a healthy Mediterranean diet. In this paper, the MAI was computed based on the diets of 23 population groups from Italy, Greece, U.S.A., Costa Rica, Chile, Spain, and Germany. High MAI values were recorded among working class men from southern Italy, and Seven Countries Study (SCS) men from the Greek islands, and the lowest among U.S.A. men and a control group of German women; surprisingly low values were recorded among Madrid men and women and participants from Spanish-speaking Latin American countries. The inversely significant correlation between the 16 SCS cohort diet MAI values and the 25-year coronary heart disease death rate previously observed was stable when an appropriate statistical analysis was used. Furthermore, MAI values of diets in elderly participants from 10 European countries followed for 10 years were inversely associated with total mortality.

Conclusions: The above results further confirm the validity of MAI, indicating that it is as good as the most utilised indexes or scores proposed for adults in Europe.