Focus on Childhood Obesity

A significant cadre of research on obesity and related themes has been published in scientific journals in recent years. Obesity is the flip side of malnutrition – including wasting and stunting – and is spreading worldwide, from the richest to the poorest countries, according to changes in traditions and lifestyle. Therefore, overweight and obesity are paradoxically close to malnutrition and undernutrition and might share some biocultural roots. 

 

Some years ago in an editorial published in Pediatric Research, Reilly and coworkers underscored the dearth of evidence around the causes of pediatric obesity, with much of the available literature being limited quality and presenting inconclusive or contradictory results. (Reilly JJ, Ness AR, Sherriff A. Epidemiological and physiological approaches to understanding the etiology of pediatric obesity: finding the needle in the haystack. Pediatr Res 2007; 61:646-52) The increasing evidence supporting the coexistence of these two opposing forms of malnutrition makes the topic of childhood obesity even more intriguing.

 

This Focus on Childhood Obesity summarizes the primary themes of research surrounding obesity, specifically the research that is not solely focused on nutrition, as recently published in Pediatric Research and the International Journal of Obesity. The themes have been grouped into three areas: (1) basic and translational mechanisms, (2) socioeconomic and lifestyle correlates, and (3) xenobiotics.

 

Regarding basic and translational mechanisms, the literature on direct biological mechanisms leading to adiposity is summarized, to include genetics and epigenetic transmission, the role of the maternal status during pregnancy (which strongly affects epigenetics) and early feeding behaviors, the emerging role of the microbiome, and fat-related proinflammatory factors with their reciprocal interactions.

 

Socioeconomic factors and related lifestyles are also critical to understanding the spread of overweight and obesity. These factors increase exposure to conditions that are negatively related to health, such as smoking, depression, and cultural influences connected to low physical activity.

 

Finally, xenobiotics (in the broad sense of "non-natural compounds") are becoming an independent topic of research because of their possible influences on the expression of genetic heredity.

 

This collection of articles suggests research avenues that may improve future etiologic studies and provides a framework for integrating the diverse body of etiologic evidence available now and in the future. Particularly important is the need for more effective preventive interventions that are based on present research; these interventions should include both biological and social backgrounds. Within this context, efforts should be undertaken to correct both forms of malnutrition–those caused by dietary excesses and those caused dietary deficiencies.