Objective: To investigate the prevalence and the trends of overweight and obesity in Finnish 5- and 12-year-old children in 1986 and 2006.
Design: Retrospective cross-sectional study.
Subjects and methods: Anthropometric data were collected retrospectively from health examinations in Tampere and in three rural municipalities. The size of the 5- and 12-year-old cohorts were 2108 in 1986 and 4013 in 2006, respectively. The body mass index (BMI) was calculated. Overweight and obesity was estimated using the International Obesity Task Force cutoff values (ISO BMI).
Results: The prevalence of overweight (ISO BMI >25) and obesity (ISO BMI >30) in 5-year-old boys in 2006 was 9.8% and 2.5% and in girls 17.7% and 4.3%, [corrected] respectively. At the age of 12 years, the corresponding figures in boys were 23.6% and 4.7% and in girls 19.1% and 3.2%. Between 1986 and 2006, the prevalence of overweight in 12-year-old children had increased 1.8 fold in boys (p < 0.001) and 1.5 fold in girls (p = 0.008). Overweight was significantly more common in rural than in urban areas.
Conclusion: During the last 20 years the prevalence of overweight has markedly increased in 12-year-old Finnish children, but remained nearly unchanged in 5-year-old children.