Thursday, September 17, 2009

Obesity prevention among schoolchildren and adolescents

Yesterday Wilma Jansen, senior researcher at the Municipal Health Service of the Rotterdam-Rijnmond area, defended her thesis entitled ‘Prevention of Childhood Obesity in a Municipal Setting’. The studies presented in her thesis further confirmed that the prevalence of being overweight in the Rotterdam area among children and adolescents is high (approximately 25%), and substantially higher than in other parts of the Netherlands. Her studies further showed that many parents do not recognize or deny their children’s overweight status.
Part of her thesis research was the description and evaluation of the ‘Lekker Fit!’ (‘nice and fit’) intervention at Rotterdam schools to contribute to obesity prevention by promotion of healthful physical activity and nutrition. The Lekker Fit! intervention combined structural changes in the school and neighbourhood environment with health education activities, with involvement of different municipal services related to education, sports and recreation, and public health. The Lekker Fit! intervention resulted in somewhat lower rates of overweight and lower mean waist circumferences among the younger participants, i.e. indications that the intervention may indeed contribute to obesity prevention.
After the thesis defence, in a symposium on local and municipal obesity prevention, Drs. Frank van Lenthe of Erasmus University medical center and Mai Chin A Paw from the department of Public and Occupational Health of the EMGO+ Institute, and Prof. Jaap Seidell, from the department of Health Sciences and the EMGO+ Institute presented their views on the issue. All speakers argued that larger and multiple changes in the micro level and macro level food and physical activity environments are needed to make meaningful changes in behavioral nutrition and physical activity.
In two articles Prof. Ken Resnicow has argued that changes in behavioral nutrition and physical activity may be better described by quantum changes and chaos theory instead of the most often used more linear health behaviour theories. A characteristics of chaos theory that is often described is that small initial differences may lead to huge consequences, e.g. the butterfly clapping its wings causing a big storm at the other side of the world. However, I believe, and the literature indicates that and the speakers, especially Jaap Seidell kind of argued the same, that for obesity prevention almost the opposite is true: we need large and many enduring changes in multiple obesogenic environments to cause small but meaningful effects in eating and physical activity behaviours, as well as overweight and obesity. The EPODE initiative, i.e. Ensamble Prévenon l'Obésité Des Enfants, may be the best example of such multiple changes in multiple environments that lead to first small but extending meaningful changes in childhood rates of overweight.