In general, obesity is associated with elevated levels of cytokines originating from both Th2 and Th1 immune responses, including interleukin (IL)-5, IL-10, IL-12, IL-13, Interferon-gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α). This evidence concerns the gene IL13 and obesity due to melanocortin 4 receptor deficiency.