A study was carried out in 1988 in Verona, Italy, to examine the relation of body fat and its localization to several risk factors for atherosclerosis in young men. Total body fat (bioelectrical impedance), waist and hip circumferences, and waist/hip circumference ratio were measured in 1,293 18-year-old men. Fasting serum levels of total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, triglycerides, and insulin, as well as systolic and diastolic blood pressure, were also measured. Significant differences were found in all metabolic and hemodynamic variables among quartiles of total body fat. Most of these differences remained significant after the authors controlled for the independent effect of fat localization and behavioral factors such as smoking, alcohol intake, and physical activity. Triglycerides, insulin, and blood pressure were significantly different among quartiles of waist/hip ratio, but these differences disappeared after the authors controlled for the independent effect of total body fat. These results indicate that in young men, irrespective of its regional localization, an excess of body fat is associated with a poor profile of risk for atherosclerosis. On the other hand, the prevalent localization of fat in the central part of the body is not independently associated with any risk factor.