Although a causal link has not yet been established, insulin resistance and OA coexistence may have different explanations, which includes the following: (1) OA and insulin resistance are both modulated by leptin levels [52]; (2) hyperglycaemia leads to increased gut mucosa permeability and absorption, which are implicated in OA [47]; and (3) insulin resistance is associated with elevated free fatty acids that may promote OA progression [53]. Here, LEP is linked to Insulin resistance.