Objective: To study the prevalence and trends in obesity in the period 1987-1991.
Design: Linear regression of average body mass index (BMI in kg/m2) and prevalence of obesity (BMI > or = 30 kg/m2) in a continuous monitoring project in three towns in The Netherlands.
Results: It was estimated that over the whole period the prevalence of obesity was 7% in men and 9% in women. After adjustment for age and educational level the prevalence of obesity increased significantly in both men with about 1.7 percentage points (+/- standard error: 0.8) and in women with 1.9 +/- 0.8 percentage points between 1987 and 1991. When stratified by 10-year age category the increase was strongest in those aged 20-29 and 50-59 years. When stratified by educational level, the increase was only significant in the lowest category (primary education and lower secondary education) and was not significant in other categories.
Conclusion: Obesity is relatively common in The Netherlands and, at least among responders to the yearly surveys, the prevalence of obesity has increased in the period 1987-1991 particularly in those with a relatively low educational level.