The different mechanisms by which obesity produces endothelial dysfunction have been studied and proven since some years ago by in vivo vascular function measurement in peripheral vessels of obese individuals (Toda and Okamura, 2013) showing that obesity reduces endothelium-dependent vasodilatation, eNOS protein expression and endothelial NO production, favoring a thicker media layer, enhancing vasoconstriction and drastically decreasing relaxation. This evidence concerns the gene NOS3 and obesity due to melanocortin 4 receptor deficiency.