Obesity is an important health problem in Poland affecting adolescents and adults. A study of a Lower Silesian population aged 20-40 years (25 400 participants), between 1993 and 2003, showed an increase in obese women from 8.9% to 15.0%, but no change in men (6.3% vs. 6.5%, respectively). Obesity occurs more frequently in girls and women (6% and 15%) compared to boys and men (4.0% and 6.5%, respectively). Estimation of obesity prevalence in various parts of Poland seems to be regionally dependent; the highest prevalence of obesity was observed in eastern regions of Poland.