Childhood Obesity

Duration

2011-2013

Coordinator

Martine Vrijheid (ISGlobal)

Funded by

RecerCaixa

Dramatic rises in obesity in children have been documented over the last few decades and this will have very important consequences for child and adult health. It is increasingly recognised that the pathway to obesity starts in the first years of life, even before children reach school age. Obesity is known to be caused by excess intake of calories and lack of physical activity, but many other putative factors have been suggested to play a role. New hypotheses center on vulnerable periods during pregnancy and in the first years of life and include maternal weight gain during pregnancy, maternal smoking, exposure to environmental pollutants, breastfeeding, and infant sleep duration. In addition, factors in the social and built environment are increasingly examined for their role in the childhood obesity epidemic. Pregnancy and early life have thus far received little attention in obesity prevention campaigns and interventions in children focusing exclusively on individual modification of the energy balance (increased energy expenditure or decreased caloric intake) have been of limited success. A better understanding is needed, therefore, of the multiple interrelated social, behavioural and environmental factors that may promote obesity in young children. Amongst new risk factors proposed for childhood obesity are environmental chemical pollutants. Experimental evidence suggests that some environmental pollutants have the capacity to interfere with endocrine systems to induce weight gain, especially when exposure occurs during pregnancy. Compounds of most current concern include industrial plasticisers, phathalates and bisphenol A (BPA), produced in very large quantities world-wide, and causing widespread exposure of the population. Also suspected of having an obesogenic effect are organochlorine pesticides (such as dichlorodiphenyl-dichloroethylene (DDE), and hexachlorobenzene (HCB)) and polychlorinated biphenyls (PCBs). The need for further examination of the role of these chemicals on children’s growth and development, particularly with respect to the current childhood obesity epidemic, has been widely recognised. In the current project we exploit the extensive data already collected in a Catalan mother-child cohort to gain further insights in the early determinants of childhood obesity. Such insights can be used both in the integration of information on “new” early-life obesity risk factors in obesity prevention strategies, as well as in risk assessments and setting of exposure guidelines for industrial agents. The aim of this project is to evaluate the influence of prenatal and early life environmental and social factors on the development of childhood obesity up to age 4 years in Catalonia. Specific objectives are to:

• Determine whether prenatal exposure to environmental contaminants is related to childhood obesity, focusing on phthalates, BPA, and organochlorine compounds (PCBs, DDE, HCB)

• Determine the influence of other early life factors on the risk of childhood obesity: prenatal maternal factors (smoking, BMI, age, weight gain) dietary factors (high fat intake, high sugar intake, folate intake, breastfeeding) physical activity and sedentary life style infancy sleep patterns social environment (social class, education, ethnicity) and the built environment (proximity to main roads, air pollution, access to playgrounds and green spaces).

• Determine the interrelationships and interactions between these environmental, behavioural and social factors in the causation of childhood obesity.