The development in body mass index, overweight and obesity in three regions in Denmark.

Background: The prevalence of overweight and obesity has increased markedly the past decades. However, recent studies have indicated that the development differ between different socio-economic groups and different geographic regions. The aim of this study was to assess the development in prevalence of overweight and obesity from 2006/2007 to 2010 by age, gender, socio-economic factors and geographical regions.

Methods: Two cross-sectional surveys in three regions in Denmark (The Capital Region of Denmark, The Central Denmark Region and The North Denmark Region) were performed in 2006/2007 and 2010. A random sample of citizens aged more than or equal to 25 years was invited to participate. The overall response rate was 57.5% (n = 177 076). Data from questionnaire and central registers were included.

Results: In 2006/2007, the prevalence of overweight, including obesity, was 54.3% and 36.8% among men and women, respectively. Of the overweight men 12.8% were obese and 11.8% women were obese. The prevalence was highest in the Northern region and among those who were older, had short education, was outside labour market, had low income and residents in rural areas. In 2010, the prevalence of overweight had increased to 56.3% and 39.6% in men and women, respectively (P < 0.0001). However, overweight increased the most in the Northern Region whereas no significant increase in body mass index was found among men in the Capital Region. Among women prevalence of overweight increased but not in those retired or above 60 years, and with high income.

Conclusion: The prevalence of overweight and obesity was high and increased. The development, however, was heterogenic.