OBJECTIVE: This study determined whether there is a critical level of visceral adipose tissue (VAT) associated with elevated coronary heart disease (CHD) risk factors in a cohort of women >45 years of age. RESEARCH DESIGN AND METHODS: Measurements of body composition (dual-energy X-ray absorptiometry), body fat distribution (computed tomography), fasting and 2-h postprandial (75-g) glucose concentrations, and fasting lipoprotein lipid and insulin concentrations were performed in 233 perimenopausal (9%) and postmenopausal women (age 59 +/- 6 years, 79% Caucasian, 16% on hormone replacement therapy). RESULTS: Women in the lowest VAT quintile (< or =105 cm(2)) had higher concentrations of HDL and HDL(2) cholesterol, lower LDL/HDL cholesterol ratios and triglyceride concentrations, and lower fasting glucose and insulin concentrations than women in the remaining four quintiles (P values <0.05-0.001). Women in the second lowest VAT quintile (106-139 cm(2)) had higher HDL and HDL(2) cholesterol and lower LDL/HDL ratios than women with a VAT > or =163 cm(2) (P < 0.05). Logistic regression analyses showed that women with a VAT of 106-162 cm(2) are 2.5 times more likely to have a low HDL cholesterol (P < 0.05), while women with a VAT > or =163 cm(2) are 5.5 times more likely to have a low HDL cholesterol (P < 0.01) and approximately 4.0 times more likely to have a high LDL/HDL ratio (P < 0.05) compared with women with a VAT < or =105 cm(2). Women with a VAT > or =163 cm(2) are at a higher risk of having impaired glucose tolerance (P < 0.01). CONCLUSIONS: A VAT > or =106 cm(2) is associated with an elevated risk, and a VAT > or =163 cm(2) with an even greater risk, for these metabolic CHD risk factors compared with women with a VAT < or =105 cm(2). These values may prove useful for defining "visceral obesity" and for identifying women most likely to benefit from preventative interventions.