Since random population sample will be analyzed and measured variables will be determined on the continuous time scale, the above mentioned population sample (500 subjects) is sensitive enough to assess relations between metabolic syndrome and indicators of oxidative stress markers and lipid metabolism. Epidemiological approach (analysis of stratified data, linear and logistic regression, and statistical modelling of multipath relations) will be used to suppress the effect of confounding factors (e.g. age, smoking, sex) on data interpretation.