The effect of eight-week nutrition education on nutrition knowledge, nutrition literacy, and Mediterranean diet in Turkish adolescents

Introduction: Adolescence, when nutritional decisions are mostly made individually, is a critical period in which eating habits are orientable. This study aims to evaluate the effectiveness of nutrition education on nutrition knowledge, nutrition literacy, and the Mediterranean diet in Turkish adolescents in the first year of high school. Methodology: This study was conducted in 47 students aged 14-16 at a high school in Ankara, Turkiye. Experimental design with pretest-posttest was used. The students were educated for eight weeks after the pretest administration. Posttests were administered after the eight-weeks intervention. Follow-up tests were administered in the sixteenth week, eight weeks after the administration of the subsequent tests. The Mediterranean Diet Quality Index for Children and Adolescents (KIDMed), Adolescent Nutrition Literacy Scale (ANSL), and self-assessment of nutrition knowledge were compared at 3-time points: pre-education, post-education, and follow-up. All the forms were used in paper format in a class setting during regular school instruction time. Results: Most of those who self-assessed their pre-education nutrition knowledge as insufficient/did not know evaluated their post-education (57.1%; p=0.027) and follow-up (50%; p=0.013) nutrition knowledge as sufficient. However, there was no significant difference between pre-education ANSL item scores and post-education and follow-up (p>0.05). None of the KIDMed items showed a significant change in the desired direction (showing healthier nutrition), either (p>0.05). Among the KIDMed items, only the change (in the negative direction) for "Has cereals or grains for breakfast" was statistically significant (p=0.044 for pre-post and p=0.010 for pre-follow-up test differences). Conclusions: Nutrition intervention improved adolescents' self-reported nutrition knowledge. However, it was insufficient to improve nutrition literacy and the Mediterranean diet. When planning dietary interventions to improve adolescents' diet or eating behaviors, it is suggested to consider individual factors related to adolescents, as well as internet and social media fields and the school/home food environment.