Effectiveness of Let’s Go! 5-2-1-0 on nutrition, physical activity and body mass index among Turkish adolescents

Objective: This study evaluated the effects of the Let’s Go! 5-2-1-0 programme on adolescents’ nutritional habits, physical activity levels and body mass index (BMI). Methods: Conducted between May 2022 and January 2023, this quasi-experimental study took place at two middle schools in Istanbul. A total of 150 adolescents participated, with one school designated as the intervention group ( n = 75) and another as the control group ( n = 75). The intervention group received six training sessions. Data were collected using a Descriptive Characteristics Form, a Healthy Habits Questionnaire, a Physical Activity Questionnaire and anthropometric measurements (height and weight). Demographic characteristics of the intervention and control groups were compared using Chi-square and t-tests, while Mann–Whitney U and Wilcoxon signed-rank tests were employed to analyse differences in pre-test, post-test and follow-up scale scores between groups. Results: Subsequent to the programme, the intervention group exhibited a significant decrease in the proportion of students with a BMI greater than 85. Improvements were noted in the consumption of low-fat milk, whole milk and 100% fruit juice, along with increased breakfast frequency, family meal participation and water intake. In addition, there was a decrease in the consumption of soft drinks and ready-made fruit juices/sports drinks. However, no significant differences in physical activity scores were found between the intervention and control groups. Conclusion: The Let’s Go! 5-2-1-0 programme promoted healthy eating habits and reduced BMI among adolescents. Nonetheless, its effects on physical activity were limited. Study findings suggest the need for the further development of physical activity initiatives within schools to encourage more active lifestyles among students.