Italian researchers have proposed that the increased risk of malignant melanoma (MM) in obese patients is due to the underlying leptin resistance. Specifically, obese patients exhibit decreased melanogenesis and melanocyte DNA repair resulting from an increase in melanocyte-stimulating hormone (MSH) antagonists (attractin, MCH, ASRP, and ASIP).
The increase in MSH antagonists in turn leads to a reduction in circulating MSH and melanocorticotropin receptors 1 and 4. In my practice in Florida we see patients of all sizes with melanoma.
Consequently we advice everyone to do a good self screening exam and learn the ABCDE of melanoma. It is not just a cancer in obese people. The risk also increases over the age of 40.
More information on this article : Obesity Risks for Melanoma