Effect of flaxseed oil on glycemic control and inflammatory markers in overweight adults with pre-diabetes: A double-blind randomized controlled clinical trial

Abstract

Introduction: Considering the progressive trend of pre-diabetes and limited evidence regarding the effectiveness of flaxseed supplement in improving glycemic indices, the aim of this study was to evaluate the effect of flaxseed oil supplementation on insulin resistance (IR) indices and inflammatory indices in overweight pre-diabetes patients. Methods: In this double-blind randomized clinical trial, 40 overweight pre-diabetic patients were divided into two groups: flaxseed oil (two 1000-mg capsules per day) and control group who received placebo for 14 weeks. Before and after the treatment, anthropometric indices, fasting blood sugar (FBS), fasting insulin, homeostasis model assessment IR index (HOMA-IR), beta-cell function, insulin sensitivity, TNF alpha, and hs-CRP were measured. Results: The results indicated a significant decrease in the weight and BMI in the treatment group, in comparison to the basic state (P = 0.001). FBS did not show a significant difference between the two groups after the treatment. Insulin and sensitivity of beta-cells diminished significantly in the flaxseed group, when compared to the baseline (p = 0.001). However, the mean changes between the two groups were not different. The mean changes of sensitivity to insulin and insulin resistance were not significant between the two groups either (p = 0.32 for S, p = 0.95 for IR). Inflammatory indices rose significantly in the control group, compared to the baseline (p = 0.03 for TNF alpha, p = 0.003 for hs-CRP). However, the mean changes between the two groups were not significant. Conclusions: The authors conclude that a 14-wk flaxseed oil supplementation may improve the weight and BMI with no effect on glycemic and inflammatory indices in pre-diabetic patients.