The effects of canola oil compared with sesame and sesame-canola oil on glycemic control and liver function enzymes in patients with type 2 diabetes: A 3-way randomized triple-blind cross-over clinical trial

Background: This study aimed to compare the effects of sesame (SO), canola (CO), and sesame-canola (SCO: a blend) oils on glycemic control markers and liver function enzymes in adults with type 2 diabetes mellitus (T2DM).

Methods: In this randomized, triple-blind, three-way, cross-over clinical trial, participants replaced their usual oil with the intervention oils for 9 weeks. Serum fasting blood sugar (FBS), fasting serum insulin (FSI), insulin resistance (HOMA2-IR), beta-cell function (HOMA2-%B), insulin sensitivity (HOMA2-%S), quantitative insulin sensitivity check index (QUICKI), as well as serum liver function enzymes were measured at baseline and end of intervention periods.

Results: Ninety-two participants completed all treatment periods. After adjusting for confounders, all treatment oils resulted in significant improvements in FSI and HOMA2-%S (P<0.05). Sesame oil, and SCO led to favorable changes in HOMA2-IR and QUICKI (P<0.05). Following CO and SCO, there was a significant decrease in HOMA2-%B (P<0.05). The sex-stratified analysis revealed that FSI and HOMA2-IR were decreased after SO compared to CO in males (P=0.024). Serum gamma-glutamyl transferase (GGT) was significantly lower following SO compared to CO in females (P=0.02), however, the difference in change values was not significant (P=0.058).

Conclusions: Sesame oil consumption appears to improve glycemic control markers in males and serum GGT in females compared with CO in patients with type 2 diabetes (registration code: IRCT2016091312571N6). This article is protected by copyright. All rights reserved.

Keywords: Canola oil; Dietary oils; Glycemic control; Insulin resistance; Liver function enzymes; Rapeseed oil; Sesame oil; Type 2 diabetes mellitus.