Prevalence of overweight and obesity in Danish preschool children over a 10-year period: a study of two birth cohorts in general practice

Aim: To determine change in the prevalence of overweight and obesity in preschool children, over a 10-year period and to identify possible predictors of overweight in 5-year-old children. Methods: Anthropometric data from birth and routine child health examinations at 3 and 5 years of age performed in general practice were collected in 5580 children from two Funen birth cohorts (1992 and 2001, respectively) representing 48% of the total population at similar age. The prevalence of overweight and obesity was classified using the International Obesity Task Force definitions. Results: In a Danish representative survey of preschool children, the average body mass index (BMI) and prevalence of overweight and obesity did not vary significantly during the 10-year period. No significant changes in mean birth weight were registered and mean BMI in the group of obese children did not increase. Overweight or obesity at 5 years was strongly associated with overweight and obesity at 3 years and with birth weight and gender. Conclusion: The prevalence of overweight and obesity was observed to be stable over a decade in Danish preschool children without changes in mean BMI in the group of obese children. A strong association between overweight and obesity at 3 and at 5 years of age was detected.