4. Discussion
This study examined the effectiveness of the three-year school-based multicomponent intervention “Nutri-školica” in changing children’s fruit and vegetable preferences, which is one of the intervention’s primary objectives. To the best of the authors’ knowledge, this is the first evaluated school-based multicomponent nutrition intervention among primary school children in Southeastern Europe. The findings demonstrate the intervention has a positive impact on children’s fruit and vegetable preferences. On a global level, this study shows how a different intervention design can influence children’s fruit and vegetable preferences. In addition, the results highlight the importance of nutritional interventions on changing children’s fruit and vegetable intake.Different sociodemographic characteristics and lifestyle may influence fruit and vegetable preferences. Therefore, at the beginning of the study, we investigated whether there was a relationship between children’s preferences and sex, weight status, and lifestyle habits. According to the available literature, it had been suggested that sex was strongly correlated with fruit and vegetable preferences, where girls had higher fruit and vegetable preferences than boys [Although fruit and vegetable preferences increased over 3 years in both the control and intervention groups, the three-year school-based multicomponent “Nutri-školica” intervention resulted in a significant increase in preferences in the intervention group compared with the control group. In addition, 70% of students in the intervention group increased preferences for fruit, 81% for vegetables, and 74% for both fruit and vegetables. There was no increase in preference for different types of fruit in the control group after three years, while preference for 11.5% different types of fruit increased in children in the intervention group after the intervention. Preference for 34.6% different types of vegetables increased in children in both groups. It should be noted that the results of the present study indicate that children’s preferences for fruit and vegetables changed most toward the varieties for which students had the least preference at baseline, which is consistent with other studies [According to the available literature, several interventions have been conducted in the last 10 years in which the effects on changing fruit and vegetable preferences of primary school children were observed [Although it is difficult to distinguish which of the individual components of the intervention was more or less successful in changing preferences, there are some similarities in the present intervention among those who experienced positive changes. The intervention “Nutri-školica” is a theory-based multicomponent intervention based on social cognitive theory, self-determination theory, and the knowledge–attitude–behavior model. Social cognitive theory and knowledge–attitude–behavior theory are the most commonly used theories to explain and predict behavior in nutritional interventions. However, self-determination theory is rarely used in interventions with primary school children according to the available literature [It is well known that children who have a greater preference for fruit and vegetables also have more diverse fruit and vegetable intake [According to the available literature, the present study is one of the few to examine the effects of the intervention on changing fruit and vegetable preferences in primary school children. The evaluation of the “Nutri-školica” intervention suggests that there is a change in preference shortly after the intervention is implemented. However, in order to assess the sustained change in preference, an evaluation needs to be conducted after a longer period of time. Children could change their preferences for fruits and vegetables as they get older if they are exposed to more different types of fruit and vegetables. Therefore, the effect of the intervention was assessed according to the difference in preferences before and after the intervention between the intervention and control groups, that is, older children. The intervention “Nutri-školica” was not fully implemented due to the COVID-19 pandemic, which could have led to a smaller change in fruit and vegetable preferences.