IMPACT OF EXCESSIVE GESTATIONAL WEIGHT GAIN IN NON-SMOKING MOTHERS ON BODY FATNESS IN INFANCY AND EARLY CHILDHOOD

Evidence from many epidemiologic studies in US and Europe shows an increasing prevalence of overweight and obesity in young children and adolescents (1-9). Childhood obesity has become an important public health policy issue because overweight children are at increased risk of many chronic diseases, such as hypertension, type 2 diabetes or dyslipidemia (10-16). Moreover, childhood obesity is also a risk factor for obesity in adulthood (17-22), which is associated with the occurrence of the metabolic syndrome, which refers to the clustering of cardiovascular risk factors, that include diabetes, obesity, dyslipidaemia and hypertension (23-26). The etiology of obesity is multifactorial and involves both physiological and environmental components. The physiological aspects of obesity include body metabolism, hormones, and the neurological components of appetite regulation (27-31). Environmental components include larger amounts of highcalorie food and lack of physical activity. It is thought that understanding the very early determinants of human obesity might help curb the prevalence of excessive weight gain in children and control the obesity epidemic. Up to now, the role of excessive gestational weight gain on obesity in the offspring has received an increasing attention, especially since the IOM report of 1990 on weight gain in pregnancy (32-34). The assessment of overweight/obese status in neonates and early childhood is under heavy debate, and there is a discussion about the best way to determine the nutritional status of children below the age of 10 in epidemiologic studies. Overweight or obesity can be considered an excess of body fat (35), but in studies on children the definition of “excess” is usually statistical rather than health related (36). The most commonly used indicators of nutritional status in children consider the relationship between weight and height of children (e.g., ponderal index – PI or body mass index – BMI). Though traditionally used in adults, they are not appropriate measures in children because children accumulate fat free mass with body growth and these measures in children correlate more weakly with body fat content measured by skinfold thickness in adults. For instance, Haggarty et al. (37) on the basis of a very big study sample (n=53, 934 term babies) found that even body weight alone was a better predictor of skinfold thickness, abdominal JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY 2011, 62, 1, 55-64 www.jpp.krakow.pl