RESUMO
The growth trends of Singapore children spanning 5 decades are reviewed, based on 8 anthropometric studies from 1957 till 2002. The heights of pre-school children and school age children appear to have optimised according to their genetic potential, but the weights and body mass indices of children still appear to be increasing from 6 to 18 years for both sexes, probably as a consequence of increasing affluence. This trend is reflected in the increasing obesity prevalence in school children over the past 30 years, and the concomitant increased morbidity associated with the metabolic syndrome, necessitates further research into the causes of obesity. Barker's hypothesis first suggested that changes in the intra-uterine environment can cause fetal adaptations which persist into adulthood, and are responsible for many chronic diseases of adult life. More recently, intense research in the field of epigenetics suggests that the environment can also influence the phenotype through gene expression, through modification of DNA methylation and histones which, in turn, influences gene expression. The challenge for the future is to determine if there are clear epigenetic changes, which are responsible for the increased prevalence of childhood and adolescent obesity, and whether these changes are transmitted through generations. Unravelling these epigenetic mechanisms may be the key to the prevention of obesity and the metabolic syndrome.