Although the mechanisms of these increases are not well understood, it isknown that child and adult obesity is associated with increased levels of circulatingcytokines such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-±), and maycontribute to an elevation in the number of circulating leukocytes.26 Here, IL6 is linked to obesity due to melanocortin 4 receptor deficiency.