Effect of Tocotrienols enriched canola oil on glycemic control and oxidative status in patients with type 2 diabetes mellitus: A randomized double-blind placebo-controlled clinical trial

Background: Tocotrienols have been shown to improve glycemic control and redox balance in an animal study, but their effects on patients with diabetes are unknown. The study aimed to investigate whether tocotrienols improves glycemic control, insulin sensitivity, and oxidative stress in individuals with type 2 diabetes mellitus (T2DM). Materials and Methods: This study was a double-blinded, placebo-controlled, randomized trial. A total of 50 patients, aged 35-60 years, with T2DM treated by noninsulin hypoglycemic drugs were randomly assigned to receive either 15 mL/day tocotrienols (200 mg) enriched canola oil (n = 25) or pure canola oil (n = 25) for 8 weeks. Fasting blood sugar (FBS), fasting insulin, total antioxidant capacity (TAC), malondialdehyde (MDA), and homeostatic model assessment for insulin resistance (HOMA-IR) were determined before and after the intervention. The data were compared between and within groups, before and after the intervention. Results: Baseline characteristics of participants including age, sex, physical activity, disease duration, and type of drug consumption were not significantly different between the two groups. In tocotrienol enriched canola oil, FBS (mean percent change: –15.4% vs. 3.9%; P = 0.006) and MDA (median percent change: –35.6% vs. 16.3%; P = 0.003) were significantly reduced while TAC was significantly increased (median percent change: 21.4% vs. 2.3%; P = 0.001) compared to pure canola oil. At the end of the study, patients who treated with tocotrienols had lower FBS (P = 0.023) and MDA (P = 0.044) compared to the pure canola oil group. However, tocotrienols had no effect on insulin concentrations and HOMA-IR. Conclusion: Tocotrienols can improve FBS concentrations and modifies redox balance in T2DM patients with poor glycemic control and can be considered in combination with hypoglycemic drugs to better control of T2DM.