IL6 and obesity due to melanocortin 4 receptor deficiency: However, systemic levels of IL‐6 have been shown to be to be increased in subjects with obesity and to be predictive of the development of type 2 diabetes.48 Yet IL‐6 deficiency in mice results in obesity, hepatosteatosis, insulin resistance, and liver inflammation49, 50; and in humans, infusion of IL‐6 improves insulin sensitivity.51 The observation of increased systemic levels of IL‐6 after VSG‐induced weight loss suggests that IL‐6 may play a beneficial role in insulin sensitivity systemically early during weight loss.