Effect of bedtime melatonin consumption on diabetes control and lipid profile

Hormonal change in carbohydrate metabolism through the circadian rhythm is well known. An impaired nocturnal insulin secretion and lower level melatonin coexist in diabetics at the end of the night period. Administration of melatonin may improve impaired insulin secretion and control hyperglycemia. In a randomized, double-blind study, 64 type 2 tics were treated for 12 weeks (period 1) with placebo, and then for another 12 weeks (period 2) with 6 mg of melatonin. Fasting blood glucose (FBG), total triglyceride (TG), total cholesterol (CHOL), high-density (HDL), and low-density lipoprotein (LDL) cholesterol and glycosylated hemoglobin levels (HbA1c) were measured at baseline, 12 and 24 weeks. Following 3 months of melatonin treatment, mean HbA1c (±standard error) was significantly lower than at baseline (7.65 % ± 0.086 % versus 7.1 % ± 0.111 %, respectively, P = 0.0001). The mean FBG level was significantly decreased at the end of the study (164 ± 5.4 versus 157 ± 5.5, respectively, P < 0.001). The HDL cholesterol level increased at the end of the study (42 ± 1.3 versus 45 ± 1.39, respectively, P < 0.05) but no significant changes in TG, CHOL, and LDL were observed. Results showed that bed time melatonin administration in patients with type 2 diabetes, improved control of diabetes. Trial registration: IRCT2012062610115N1, http://​en.​search.​irct.​ir/​search?​query=​melatonin+and+re​zvanfar