RESUMEN
During last decades, a departure from health-related lifestyles has been observed among adolescents. Evidence reports that healthy lifestyles could be predictors of better mental health status. The aims of the SESSAMO Project are: 1) to assess the association between lifestyles and physical and mental health; 2) to assess how self-concept and stressful life events can modulate these associations; and 3) to establish the role of social determinants in the lifestyle and in adolescents' health. The SESSAMO Project is a prospective cohort carried out in Spain. Students aged 14-16 years (2nd-4th ESO) and their parents are invited to participate. Baseline data are collected through on-line, validated, self-administered questionnaires through a digital platform. Information on lifestyles, stressful life events and self-concept are collected. Screening of depression, anxiety, eating disorders, suicide risk, psychotic experiences and COVID impact is assessed. Every three years, up to age of 25, participants will be contacted again to update relevant information.