In an effort to identify plasma lipids that could be biomarkers or causes of insulin resistance with steatosis in people with obesity, we evaluated the plasma lipidome in three distinct groups separated by adiposity, hepatic steatosis, and insulin sensitivity, assessed by using the hyperinsulinemic-euglycemic clamp procedure: i) insulin-sensitive lean (ISL, n = 13); ii) insulin-sensitive obese (ISO, n = 14); and iii) insulin-resistant obese with hepatic steatosis (IROS, n = 13). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.