The prevalence of overweight and obesity in 380 counties in Poland: A retrospective analysis of the National Health Fund dataset

Excess body weight is an emerging public health problem. This study assesses the prevalence of overweight and obesity in 380 counties in Poland using the official, population-based data. This study is a retrospective analysis of the dataset published on October 1, 2025 by the National Health Fund within the project called “Healthy Data.” Since March 2025, primary care providers (family doctors) in Poland have been obligated to report patients’ height and weight during the first visit in a given year. The following BMI categories were defined: underweight (BMI < 18.5), normal weight (BMI 18.5–25.0), overweight (BMI 25–30.0), and obesity (BMI ≥ 30). Data on 13,402,601 adult individuals were included in the analysis. The overall prevalence of overweight was 37.7% and the prevalence of obesity was 26.8%. In total, 8,646,885 individuals (64.5% of the total population) had excess body weight. In 67.6% of all 380 counties in Poland, the prevalence of excess body weight (BMI ≥ 25) was between 65% and 70% of the county’s population. The highest prevalence of excess body weight (overweight or obesity) was in Łosicki County (72.4%), and the lowest in Poznań County (55.8%). The findings from this study revealed health disparities related to the prevalence of overweight and obesity in Poland, with the highest prevalence being in northeastern Poland and the lowest in large cities.