Increased fasting triglyceride levels are associated with hepatic insulin resistance in Caucasian but not African-American adolescents.

Increased lipid levels are related to insulin resistance in children and adults (1–3). Insulin resistance occurs due to an inability to suppress hepatic glucose production (HGP) or to stimulate peripheral glucose uptake. It is not clear whether hyperlipidemia primarily affects hepatic or peripheral insulin sensitivity. In this study, the stable-labeled, frequently sampled intravenous glucose tolerance test (4–7) was used to measure total-body insulin sensitivity (Si), peripheral insulin sensitivity (Si*) (5), and hepatic insulin resistance (HIR) (8) in African-American and Caucasian adolescents.