Insulin resistance and the vascular complications of diabetes include activation of the inflammation cascade, endothelial dysfunction, and oxidative stress. The comorbidities of diabetes, namely obesity, insulin resistance, hyperglycemia, hypertension and dyslipidemia collectively aggravate these processes while antihyperglycemic interventions tend to correct them. Increased C-reactive protein, interleukin 6, tumor necrosis factor alpha and especially interstitial cellular adhesion molecule-1, vascular cellular adhesion molecule-1, and E-selectin are associated with cardiovascular and non-cardiovascular complications of both type 1 and type 2 diabetes. We sought to review the clinical implications of the inflammation theory, including the relevance of inflammation markers as predictors of type 2 diabetes in clinical studies, and the potential treatments of diabetes, inferred from the pathophysiology.