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.
[Selective primary obesity prevention in children].
Obesity in children is characterized by a rapid gain of weight starting at an age of 4 to 5 years. We investigated whether low threshold prevention prevented a further increase of the Standard-Deviation-Score of the BMI (BMI SDS) in children with impending obesity.
                The network CrescNet collected data from more than 300,000 children. We selected 365 children with impending obesity (age 4 to 7 years). After randomisation the study population was divided into an intervention group (180 children) and a control group (185 not informed children). The paediatrician carried out a low threshold intervention consisted of an age-adapted nutrition and exercise program to inspire the awareness of the adequate nourishment and motion.
                59 children of the intervention group opted for a participation and 49 of them took part to the end of the study. This study population stabilized their BMI SDS (p < 0.025). The children randomised in the intervention group who were not interested to participate, and the children of the control group increased their BMI SDS within the observation period of one year (p < 0.001, p = 0.002). According to nutrition diaries a decrease energy intake of the participants of the intervention group was detected. The percentage of protein intake was particularly remarkable, amounting to 363 % fulfillment of demand at the beginning of the study and 274 % at the end. A regression analysis suggests that an intervention and also the approval to take part in the study had a significant influence on changes in BMI SDS.
                A low threshold intervention in early childhood could successfully prevent an increase of obesity.