An investigation was conducted in 8 to 18 year old children to determine interrelationships among Type 1 diabetes (DM 1), bone mass, nutrient intake and physical activity. Bone mineral content (BMC, g), bone area (BA, cm 2), and bone mineral density (BMD, g/cm2) were measured by dual-energy x-ray absorptiometry in children with (n = 27 females, 24 males) and without (n = 34 females, 34 males) DM 1. Nutrient intake was assessed using 3-day food records and physical activity by a validated questionnaire. Data was analyzed by two-way ANOVA and correlation analysis. Based on the results a second investigation was undertaken to study further the role of insulin in bone development, and the effect of n-3 PUFA on bone development in insulin deficiency. Weanling male Sprague-Dawley rats (n = 80) were randomly assigned to one of six groups: saline injection + pair-weigh (n = 20) or ad lib feeding (n = 20), or streptozotocin injection to induce insulin deficiency + ad lib feeding (n = 40). Animals were fed diet containing either soy oil or fish oil (menhaden + corn oil). (Abstract shortened by UMI.)