This study aims to improve comparability of available data within the World Health Organization (WHO) European Region taking into account differences related to the aging of the population. Surveys were included if they were conducted on adults aged 25–64 years between 1985 and 2010 in the WHO European Region. Overweight/obesity prevalences were adjusted to the European standard population aged 25–64. Data were entered for each of the 5-year categories between 1981 and 2010. Measured height and weight data were available for males in 16 and females in 24 of the 53 countries. The 50–64-year-olds had higher prevalence of overweight and obesity as compared to the 25–49-year-olds. This pattern occurs in every country, by male and female, in almost all surveys. Age-standardized overweight prevalence was higher among males than females in all countries. Trend data showed increases in most countries. Age-standardized maps were based on self-reported data because of insufficient availability of measured data. Results showed more countries with available data as well as the higher category of obesity in the later surveys. Measured values are needed and age adjustment is important in documenting emerging overweight and obesity trends, independent of demographic changes, in the WHO European Region.