BACKGROUND: Adiponectin is a fat cell-secreted cytokine, which has been reported to improve insulin sensitivity and have antiatherogenic properties. However, it is still unclear whether resistin plays a significant role in the development of insulin resistance in humans. The aim of this study was to investigate the relationship of the adiponectin and resistin concentrations with insulin resistance, metabolic markers and adiposity in healthy and type 2 diabetic subjects. METHODS: Eighty-three type 2 diabetic and 139 healthy subjects were studied. Blood samples were drawn after fasting to determine the fasting plasma glucose, insulin, resistin, adiponectin, total cholesterol, triglyceride and HDL-cholesterol levels. The subcutaneous and visceral fat areas were measured at the umbilical level using computed tomography. RESULTS: The serum adiponectin concentrations were significantly lower in the diabetic(6.7+/-2.3microgram/mL) than in the obese(8.2+/-2.4microgram/mL, P<0.01) and non-obese subjects(9.9+/-4.5microgram/mL, P<0.01). The serum resistin concentrations were Similar between the non-obese, obese and type 2 diabetic subjects. From a multiple regression analysis, the fasting glucose, HDL-cholesterol and HOMA-IR were found to be independent determinants of the log of the adiponectin level in the diabetes group. In healthy subjects, the gender, BMI, HOMA-IR, visceral fat area and HDL-cholesterol were associated with the log of the adiponectin level. However, the log of the resistin level was not associated with the markers of insulin resistance and obesity. CONCLUSION: This study showed that the serum adiponectin concentration was closely related to the insulin resistance marker in both healthy and type 2 diabetic subjects. However, the resistin concentration was not associated with the markers of insulin resistance and/or obesity.