Abstract Adolescents tend to neglect food and their eating pattern is influenced by several factors. Adolescents’ health literacy substantiates their ability to respond to the growing demands of health, being linked to health promotion in several areas, including food. The goal of this work was to analyze the relationship between sociodemographic and contextual variables with secondary school students’ food literacy. A quantitative, cross-sectional, descriptive and analytical study was carried out with a sample of 181 nonprobabilistic secondary school students, aged between 16 and 21 years (mean = 18.09 years ± 1.45), mostly female (58.0%), from 11th grade (35.4%), who are part of a secondary school in central Portugal. As a tool for data collection, the questionnaire of the project “Your PEL – Promote and Empower for Health Literacy in the young population” was used, aggregating three areas: eating behaviors, harmful consumptions and sexuality. The results showed that 58.6% of young people eat 4–5 meals a day, consume fast food weekly (79%) and eat soup (82.3%). Additionally, they eat fruit and vegetables on a daily basis (94.5 and 83.4%, respectively). The results further showed that 10th grade students have higher levels of health and food literacy. It was observed that both girls and boys are interested in receiving information regarding food, transmitted through social networks and by a communication application (84.5 and 73.5%, respectively), with significant differences (χ ² = 4.768; p = 0.028). Adolescents face unique health challenges and a critical level of health literacy compromises their understanding of information about diet and future health. The results indicate that educational plans to empower adolescents in these areas, which integrate gender and age differences and sources of information as important variables to be considered, are pivotal for increasing levels of health and food literacy.