Adolescence is a critical period for brain maturation and mental development. For this reason, we believe that studying which foods can be beneficial at this stage will allow us to create healthier dietary recommendations to improve the health of our future generations. The Smart Snack study, coordinated by the Barcelona Institute for Global health (ISGlobal), is being carried out between 2016 and 2018 thanks to the active and voluntary collaboration of more than 700 teenagers, their respective families and professionals from 12 schools in Barcelona. Our aim is to assess whether there are changes in the mental abilities of our young participants. Through computer-based activities, and biological indicators of health obtained by clinical exams, we will determine if changes are observed after following a simple and specific diet intervention for 6 months. Our team is made up by experts in diet and mental health, who are always willing to inform and take care of our participants’ health, as well as giving the deserved scientific value to the entire school and community involved in the study.