[Effects and costs of The Healthy Primary School of the Future].

Objective: To study school lifestyle interventions for elementary school children (The Healthy Primary School of the Future).

Research Question: What are the effects of the introduction of increased physical activity with or without healthy nutrition on health behaviour and BMI of young children and what are the costs of this program?

Design: Prospective controlled non-randomized study with nearly 1700 children in Parkstad (South-East Netherlands).

Results: Preliminary results after two years show that the combination of increased physical activity and healthy nutrition result in a decreased BMIz-score (-0.