Presentación

Obesity became a serious concern of global relevance over the past few years, being recognized as one of the foremost determinants of chronic diseases in the world. Incidence and prevalence rates of obesity have been steeply increasing for at most three decades in United States and Europe, and now, they are showing the same, lagged pattern in newly industrialized and emerging countries. Reasons for the rising prevalence include urbanization of the world's population, increased availability of food supplies, and reduction of physical activity.¹

Mexico is fully fitting in this picture, having one of the largest prevalence of young obese, large rates of inadequate physical activity, in particular in urban areas, and a high prevalence of malnutrition, with under- and over-nutrition coexisting in the country.

This special issue of Salud Pública de México aims at addressing the obesity issue having in mind the multi-factorial perspective which is nowadays the standard approach in dealing with the phenomenon. Indeed, for sake of simplification, we could try to organize factors associated with obesity as an interaction among individual predisposition, social and built environment.

Actions to fight obesity are difficult, properly in view of the multifactorial nature of the phenomenon. This is recognized in the paper of Morales Ruán and colleagues, where the effectiveness of interventions aimed at reducing obesity in schoolchildren is shown to be dependent from the socio-economic status of the families where the children live. Socio-economic level of the families is also at the ground of the effectiveness of educational initiatives, which are inconsistently reaching different strata of population. Still education must be a priority in the fight against obesity, and this is strongly advocated by Bonvecchio and colleagues, in spite of the possible obstacles facing the implementation of such programs. Such difficulties arise also in terms of a reduced penetrance of healthy nutrition messages: this is sadly confirmed by the findings of Jiménez Aguilar and colleagues, who estimate that in Mexico, only 3 out of 10 children adhere to nutritional recommendations of eating fruit and vegetables. Also water consumption is inadequate, and strategies for fostering increased access to water in everyday's life are reported by Elder and colleagues. Innovative approaches, like narration, to promote healthy lifestyles may result promising, and the paper of Ríos Cortázar and colleagues describes a real experience on that. Regarding possible targets for actions against obesity, advertising of unhealthy food of children is widely considered as inappropriate. The paper of Théodore and colleagues reports on the recent developments of knowledge in the field updating at the same time on the current Mexican situation, whereas the work of Dibildox recalls major factors and their interaction, providing a behavioural perspective to childhood obesity.

Nevertheless, local approaches in fighting obesity must coexist with the understanding that, in a globalized world, the framework must be investigated also keeping a broader, international perspective in hand. This is emphasized by both the contribution of Gregori and of De Hoyos Parra, who comment on the relationships among local and international policies to reduce obesity.

Dario Gregori, PhD.*

* Unit of Biostatistics, Epidemiology and Public Health, Department of Cardiac, Thoracic and Vascular Sciences, University of Padova. Padova, Italy. dario.gregori@unipd.it.

References

1. Grundy SM. Multifactorial causation of obesity: implications for prevention. Am J Clin Nutr 1998;67(3):563S-572S.         [ Links ]