We found strong evidence to support beneficial effects of child obesity prevention programmes on BMI, particularly for programmes targeted to children aged six to 12 years. However, given the unexplained heterogeneity and the likelihood of small study bias, these findings must be interpreted cautiously. A broad range of programme components were used in these studies and whilst it is not possible to distinguish which of these components contributed most to the beneficial effects observed, our synthesis indicates the following to be promising policies and strategies:
·         school curriculum that includes healthy eating, physical activity and body image
·         increased sessions for physical activity and the development of fundamental movement skills throughout the school week
·         improvements in nutritional quality of the food supply in schools
·         environments and cultural practices that support children eating healthier foods and being active throughout each day
·         support for teachers and other staff to implement health promotion strategies and activities (e.g. professional development, capacity building activities)
·         parent support and home activities that encourage children to be more active, eat more nutritious foods and spend less time in screen based activities
However, study and evaluation designs need to be strengthened, and reporting extended to capture process and implementation factors, outcomes in relation to measures of equity, longer term outcomes, potential harms and costs.
Childhood obesity prevention research must now move towards identifying how effective intervention components can be embedded within health, education and care systems and achieve long term sustainable impacts.
Prevention of overweight in preschool children: results of kindergarten-based interventions.
Given the increasing prevalence of pediatric obesity, we evaluated two kindergarten-based strategies for reducing overweight in preschool children in the Haute-Garonne Department in France.
                Kindergartens (n=79) were randomly assigned to one of the two strategies and followed for 2 years. In the first group (Epidémiologie et prévention de l'obésité infantile, EPIPOI-1), parents and teachers received basic information on overweight and health, and children underwent screening to identify those with overweight (body mass index (BMI) > or = 90th percentile) or at risk for overweight (BMI between 75 and 90th percentile), who were then followed up by their physicians. EPIPOI-2 children, in addition, received kindergarten-based education to promote healthy practices related to nutrition, physical activity and sedentary behaviors. Data on control children from non-intervention kindergartens (n=40) were retrieved from medical records at the Division of School Health.
                At baseline, groups differed significantly on age and school area (underprivileged/not). Owing to a significant interaction between school area and group, analyses were stratified by school area. At baseline, groups did not differ on overweight prevalence and BMI z-scores for any school area. After intervention, prevalence of overweight, BMI z-score and change in BMI z-score were significantly lower in intervention groups compared with controls in underprivileged areas. Using multilevel analysis adjusted for potential confounders, a significant effect on overweight prevalence at the end of the study was noted for EPIPOI-1 in underprivileged areas only (odds ratio and 95% confidence interval: 0.18 (0.07-0.51). In non-underprivileged areas, the gain in BMI z-score was lower in EPIPOI-2 group compared with control and EPIPOI-1.
                Our results suggest that simple measures involving increasing awareness on overweight and health, and periodic monitoring of weight and height with follow-up care when indicated, could be useful to reduce overweight in young children from underprivileged areas. A reinforced strategy with an education component, in addition, may be indicated in children in non-underprivileged areas.