Abstract
Background/Objectives: This paper aims to assess the unhealthy dietary habits and sedentary behaviours among adolescents and young adults simultaneously. Methods: The sample consists of 682 participants aged 10-24 years old (58.9% males and 68.2% aged 15-19 years old), recruited for the ALIMA (ALImentazione Multiculturale negli Adolescenti) study in both secondary schools and youth aggregation centres, located in Rome. The study utilizes structured questionnaires to gather data on anthropometric measurements, eating habits, alcohol consumption, physical activity, and sedentary behaviours. Data are analyzed by using the Pearson chi-squared test. Results: Excessive screen time (>3 h/day) and inadequate dietary habits (insufficient consumption of fruit, vegetables, and legumes, skipping breakfast, and a high consumption of sugar-sweetened beverages and alcohol) are observed in the total sample, but mainly in older adolescents aged 15-19 years old. The adherence to the MD, measured via the KIDMED index, is significantly different among the three age groups (p = 0.001); 47.8% of the sample has a medium adherence, while among those with a low adherence, the highest percentage is represented by older adolescents (39.8%); those with foreign-born parents have healthier diets, whereas lower parental education correlates with unhealthy behaviours. Conclusions: These results highlight the need for targeted interventions tailored to adolescents and young adults to encourage healthier lifestyle choices.