This project investigates the relationship between childhood nutrition and breast cancer risk factors, including age at menarche, adult height, weight, and fatness. Secondary objectives include tracking the development of obesity from birth through young adulthood, to identify the contribution of diet to the development of childhood and adult obesity, and to explore the feasibility of retrospective childhood dietary assessment. Background: Early age at menarche, as well as obesity, weight gain, and tallness are associated with increased risk of breast and other cancers. Caloric intake in excess of requirements during childhood and adulthood is considered the primary cause of obesity, and believed to contribute to the timing of hypothalamic-gonadal maturation and menarche and to greater body height for any given hereditary predisposition of stature. Identification of critical periods and high-risk diets would be useful to breast cancer prevention strategies. METHODS: Serial childhood dietary diary records, anthropometric data (including height, weight, skinfold thickness) and demographic characteristics available from the Fels Study within the Division of Human Biology of the Wright State School of Medicine were retrieved for 106 female participants. Evaluable nutrients include total energy, fat, protein, and carbohydrate, saturated, polyunsaturated, and monounsaturated fat; cholesterol; dietary fiber; and vitamins and minerals (from food and supplementary sources). PROGRESS: Dietary data have been coded and linked with the anthropometric (childhood through adulthood) and menarche data for the 106 girls. Analysis shows the expected trends in food intake with growth and development (e.g., increasing energy, protein, and fat intake with age). Age at menarche is inversely associated with both energy and absolute fat intake in childhood, but not with percent of calories from fat. The interrelationships between diet and anthropometry (including obesity) at various ages and age at menarche will be analyzed in detail. A subsample of 35 girls, now adults, completed two food frequency questionnaires that asked about their dietary intake during high school, and these data will be compared to their adolescent diets to assess the feasibility of such remote recall.