The aim of the study is to describe the overall diet and potential effects of gender, ethnicity, family income, and parents' education on dietary patterns in adolescents aged 11 to 20 years who participated in a cohort study in 12 Southern California communities.

A validated 131-item youth/adolescent food frequency questionnaire was administrated among 3,201 participants in the Children's Health Study at follow-up visits between 1998 and 2000. Sociodemographic characteristics included ethnicity, family income, and parents' education. Stratified analysis and analysis of covariance were used to describe the intakes of selected nutrients and food groups.

Mean intakes for all nutrients except calcium met 100% of the Recommended Dietary Allowances. Average daily food intakes were below the minimum recommended number of servings for all major food groups. The majority of subjects had an excessive intake of added sugar. A gender difference was found in intakes of energy, total fat (TF), saturated fat (SF), monounsaturated fat (MUSF), and calcium (P < 0.05). Non-Hispanic Whites had the lowest intakes of fruits while Blacks and Asians had significantly higher intakes of vegetables (P < 0.05). Subjects from higher income families had significantly higher intakes of polyunsaturated fat, protein, calcium, and folate and more frequently consumed dairy products. Intakes of TF, SF, MUSF, and cholesterol decreased as parents' education levels increased. Subjects from families with parents who had higher educational attainment were more likely to meet the recommendations of dairy products, fruits, and vegetables.

Overall, subjects in our study did not have healthy eating habits. Dietary patterns varied by sex, ethnicity, income, and education.