The paper contains data on prevalence of low, normal, excessive body mass and obesity among urban male populations aged 20-54 years in different regions. Relative risk of death associated with body mass was estimated on the basis of a twenty years prospective study of sample populations in Moskva and St-Peterburg and level of attributed risk was used for assessment of contribution of body mass to cardiovascular mortality and mortality from other chronic diseases. Levels of main risk factors, smoking intensity and alcohol consumption were studied in deciles of body mass index distribution.