Childhood obesity: of growing urgency

To the Editor: A number of recently published articles indicate that the prevalence of overweight and obesity in children is increasing at an alarming rate on a national1 and international2 level.

Overweight children are more likely to become overweight adults and to experience chronic health problems associated with adult obesity. We report results obtained from a survey of primary schoolchildren on the New South Wales Central Coast which extends the time series from that in the article by Magarey and colleagues (1985 and 1995 data)1 to the year 2000.

We undertook a cross-sectional study of children at a Central Coast primary school in November 2000 as part of a community study. This study was approved by the Central Coast Health Ethics Committee.

All children in each class were asked to take part. With parental consent, weight and height were measured in children from all class groups (aged 7–11 years) by child health nurses using standardised procedures. Children were classified as overweight or obese using the standard international cutoffs for body mass index.3 They were compared with data obtained during the 1985 Australian Health and Fitness Survey (AHFS85) and the National Nutrition Survey of 1995 (NNS95).1

A total of 268 children (127 girls, 141 boys) were surveyed (average of 25 girls and 28 boys of each age). This represented a 70% response rate. The Table shows that the incidence of overweight and obesity in Australian children has continued to increase, with relative risks for the increase between 1985 and 1995 of 1.37 (95% CI, 1.07–1.75) for boys and 1.82 (95% CI, 1.49–2.22) for girls, and relative risks for the increase between 1995 and 2000 of 1.71 (95% CI, 1.21–1.43) for boys and 1.21 (95% CI, 0.87–1.67) for girls. Our findings indicate a marked increase in proportions for boys in only five years since NNS95. While the increase for girls was not statistically significant, the pattern is consistent.

Thus, the incidence of overweight and obesity in Australian children is steadily increasing. Importantly, according to the 1996 Census Socio-Economic Indexes for Areas,4 the school we surveyed is situated in an area ranked in the middle quintile for relative socioeconomic disadvantage (state and national average), and is immediately adjacent to one 4th- and several 1st-quintile and 2nd-quintile areas. We believe our findings are representative of the Australian population of children.

The challenge to healthcare workers is significant. The National Health and Medical Research Council's Acting on Australia's weight5 identifies goals for preventing further weight gain in adults, and eventually reducing the proportion of the adult population that is overweight or obese, and to ensure the healthy growth of children. Recommended strategies range from national dietary and physical activity guidelines to increasing physical activity through the design of towns, transport systems and public recreational facilities. Effective strategies are urgently needed to alter food intake and physical activity at individual, school, community and population levels.