Dietary patterns among 13-y-old Portuguese adolescents

The aim of this study was to identify dietary patterns in 13-y-old adolescents and to evaluate their association with socioeconomic and behavioral factors.

Data from 1489 adolescents born in 1990 and enrolled in schools of Porto, Portugal, in 2003-2004 (EPITeen study) were analyzed, after excluding those without information on the food frequency questionnaire and the outliers. The questionnaire items were grouped into 14 food groups and dietary patterns were identified by cluster analysis (k-means). Their association with participants' characteristics was computed using multinomial logistic regression.

Four dietary patterns were identified. The pattern healthier (16.1%) was characterized by the highest consumption of seafood, soup, vegetables/legumes, fruit, and added fats. The dairy products pattern (29.7%) showed the highest consumption of dairies. The pattern fast food and sweets (14.2%) presented the highest intake of fast food, sweets and pastry, soft drinks and coffee or tea. The lower intake pattern (40%) was characterized by a lower consumption of the majority of food groups. A higher odds of belonging to the fast food and sweets pattern, compared with the lower intake pattern was found among adolescents spending more time watching TV on the weekends (>360 min: odds ratio [OR], 2.09; 95% confidence interval [CI], 1.23-3.57) and among those consuming four to seven fried meals per week (OR, 3.96; 95% CI, 2.27-6.90). Adolescents with highly educated parents were less likely to belong to the fast food and sweets group.

Unhealthier behaviors and lower socioeconomic position were the main factors associated with the unhealthier dietary pattern (fast food and sweets). This information should be considered in the development of health-promotion interventions.