Bishay RH, Tonks KT, George J, et al. - In this observational study, experts aspired to explore whether plasma bile acid (BA) is elevated in human obesity and/or insulin resistance. Seventy-one adult volunteers formed four groups: lean insulin-sensitive (BMI ≤ 2 5kg/m², HOMA-IR < 2.0, n = 19), overweight/obese non-diabetic who were either insulin-sensitive (Ob_sensitive, BMI > 25kg/m², HOMA-IR < 1.5, n = 11), or insulin-resistant (Ob_resistant, BMI > 25kg/m 2, HOMA-IR > 3.0, n = 20), and type 2 diabetes (T2D, n = 21). In humans, BA concentrations correlated with abdominal, visceral and liver fat, although an etiological function remains to be confirmed in insulin resistance.