Our observation is similar to that of Melinand colleagues24; however, the association of smoking with poor glycaemic control is not consistent in all available studies.25,26 Tobacco may negatively affect glycaemic control by stimulating the sympathetic system responsible for glycogenolysis and gluconeogenesis27 and stimulating the renin–angiotensin system on the basis of post-receptor insulin resistance.28 Here, REN is linked to Insulin resistance.