Left ventricular (LV) structural alterations were associated with increased cardiovascular morbidity and mortality in a middle-aged and older population. The aim of this study was to determine childhood and adulthood cardiovascular risk predictors of LV geometric remodeling in a biracial (black-white) population of young adults. As part of the Bogalusa Heart Study, echocardiographic examinations of the heart were performed in 824 adults (age range 24 to 44 years, average 36; 41% men, 69% white) who had risk-factor variables in their childhood. Eccentric LV hypertrophy and concentric remodeling were the most commonly encountered LV geometric changes in this young adult population (4.7% vs 1.8% for concentric LV hypertrophy). In adulthood, subjects with eccentric and/or concentric LV hypertrophy compared with normal geometry were more likely to be obese and/or diabetic and had significantly increased body mass index, waist circumference, systolic and diastolic blood pressures, glucose, insulin, hemoglobin A1c, total/high-density lipoprotein cholesterol ratio, triglycerides, and urinary albumin-creatinine ratios. In multinomial logistic regression analyses, both adulthood and childhood body mass index were significant determinants of eccentric LV hypertrophy (odds ratios [ORs] 1.15 and 1.19). The presence of diabetes mellitus in adulthood (OR 8.25) and diastolic blood pressure in childhood (OR 1.14) were significant predictors of concentric LV hypertrophy. In adults, blacks had higher ORs for concentric LV hypertrophy and related to diabetes and systolic blood pressure. In conclusion, in this community-based study of young adults, eccentric LV hypertrophy was more frequent and obesity since childhood was the only consistent and significant determinant of this type of adverse cardiac remodeling.