[Is the Swiss population gaining body weight? Body mass index in insurance applications between 1950 and 1990].

In this study 4435 insurance applications to the Swiss Life insurance company ("Rentenanstalt") by individuals aged 20-39 years from the time period 1950-1990 were evaluated. Each application contained the self-reported body weight, height, and other informations such as martial status or city of residence. For each individual the body mass index (BMI) was computed and the prevalence of overweight and obesity for each year was calculated using standard definitions. This is the first study which tries to determine the prevalence rates of overweight and obesity in Switzerland over time. The absolute body weight (kg) increased continuously from 1950 to the year 2000. The most pronounced increase was seen in individuals (aged 20-29 years) above the 90th percentile of body weight and BMI, i.e. already overweight and/or obese individuals showed the largest increase in body weight. In men (aged 20-29 years) the prevalence of overweight increased between 1980 and 1990 by more than 10% to a prevalence rate of 25%. In women (aged 20-29 years) the prevalence of overweight increased continuously from 1960 onward and reached a rate of 10.5% in 1990. In the age group of the 30-39 years old individuals no change in the prevalence rates was observed. These data suggest that there is a trend for an increased prevalence of overweight in Switzerland. Since the study sample was not representative for the Swiss population the results have to be interpreted with caution only. Nevertheless the results are in agreement with the trends in other countries and it can be assumed that similar developments do occur also in Switzerland.