Fat distribution and health in obesity.

Although independent associations of visceral fat with the insulin resistance syndrome were previously reported in obese women, the importance of truncal subcutaneous fat in this syndrome is controversial. The method by which the various fat depots are measured may be the reason for the underlying controversy. In the past five years, we have used various methods to measure visceral versus subcutaneous fat distribution in Caucasian (C) and African-American (AA) women and have related it to insulin sensitivity (SI) and to blood lipids, particularly fasting serum triglyceride levels (TG). Elevated TG levels in obese women were best predicted by an increased amount of visceral fat, whereas the amounts of truncal and peripheral subcutaneous fat did not have an impact on them. These results were confirmed, regardless of the method used to measure the fat depots. Insulin resistance (low SI) in obese women was predicted by both an increase of visceral and of upper-body (truncal) subcutaneous fat. However, measurements of the entire visceral and truncal subcutaneous fat volumes may be needed to confirm this latter association.