peer reviewed ; STUDY: To analyse the usual dietary habits of Belgian adolescents from a high cardiovascular risk population. METHODS: A food frequency questionnaire (57 items) was administered to the whole sample. Complementary questions specified some types of food (eg fat content). A subgroup of 234 adolescents gave detailed information on portion size (picture book and food samples). SETTING: Twenty-four secondary schools in the Belgian province of Luxembourg. SUBJECTS: A total of 1,526 adolescents (12-17y) selected by a multiclustered stage sampling (participation: 83.6%). RESULTS: Respectively 46% and 60% of the adolescents did not eat fruit and vegetables daily. Most of the adolescents (72%) consumed at least one dairy product daily. The frequent consumption of chocolate and French fries indicated the strong cultural influence on dietary habits while imported foods (like hamburgers) had little success. One-third of the adolescents (33%, n = 509) drank alcohol at least once a week and this proportion rose to 57% in the oldest age group. Boys and girls differed significantly in their diet, with girls choosing healthier foods. Dietary habits, in particular drinking habits, differed also significantly between education levels, assessed by the learning option of the participants. The semi-quantitative questionnaire showed that two-thirds of the adolescents had a lipid intake (mainly saturated fatty acids) which exceeded 35% of the total caloric intake. Complex carbohydrates represented less than half of the total carbohydrates intake. CONCLUSION: The study of the diet of Belgian adolescents confirmed the strong influence of tradition, in particular on the consumption of high fat content foods. The promotion of healthy diet in adolescents should consider the cultural influence, even for this young age group