Brzeziński M, et al. - In the present study, the researchers sought to determine the prevalence of lipid disorders in overweight and obese children and adolescents engaging in an integrated weight reduction programme. The programme accepted individuals residing in Gdańsk (aged 6, 9–11 and 14 years old) with BMI above the 85th percentile for age and sex, according to the Polish percentile charts according to the “6-10-14 for Health” programme implementation schedule. One thousand nine hundred forty-eight patients underwent full anthropomethric and blood work measurements. Decreased high-density lipoprotein cholesterol levels and elevated low-density lipoprotein cholesterol were the most common lipid disorders. No strong connection was found between lipid disorders and age, gender, birth weight, gestational age at birth or body composition. Such a repeated occurrence of lipid disorders in children and adolescents population should be an significant warning signal at both the patient and community level. Efficient screening approaches should not only be introduced from an early age for overweight and obese children but also therapeutic measures are needed.