Clinical and metabolic response to flaxseed oil omega-3 fatty acids supplementation in patients with diabetic foot ulcer: A randomized, double-blind, placebo-controlled trial

Background: Data on the effects of flaxseed oil omega-3 fatty acids supplementation on wound healing and metabolic status in subjects with diabetic foot ulcer (DFU) are scarce. Objective: This study was conducted to evaluate the effects of flaxseed oil omega-3 fatty acids supplementation on wound healing and metabolic status in subjects with DFU. Methods: The current randomized, double-blind, placebo-controlled trial was conducted among 60 subjects (aged 40-85 years old) with grade 3 DFU. Subjects were randomly allocated into two groups (30 subjects each group) to receive either 1000 mg omega-3 fatty acids from flaxseed oil supplements or placebo twice a day for 12 weeks. Results: After the 12-week intervention, compared with the placebo, omega-3 fatty acids supplementation resulted in significant decreases in ulcer length. (- 2.0 +/- 23 vs. -1.0 +/- 1.1 cm, P = 0.03), width (-1.8 +/- 1.7 vs. -1.0 +/- 1.0 cm, P = 0.02) and depth (-0.8 +/- 0.6 vs. -0.5 +/- 0.5 cm, P = 0.01). Additionally, significant reductions inserum insulin concentrations (-4.4 +/- 5.5 vs. + 1.4 83 mu lU/mL, P = 0.002), homeostasis model of assessment-estimated insulin resistance (-2.1 +/- 3.0 vs. + 1.0 +/- 5.0, P = 0.005.) and HbAl c (- 0.9 +/- 1.5 vs. -0.1 +/- 0.4%, P = 0.01), and a significant rise in the quantitative insulin sensitivity check index (+0.01 +/- 0.01 vs. - 0.005 +/- 0.02, P = 0.002) were seen following supplementation with omega-3 fatty acids compared with the placebo. In addition, omega-3 fatty acids supplementation significantly decreased serum high sensitivity C-reactive protein (hs-CRP) (- 25.5 +/- 31.5 vs. -82 +/- 18.9 mu g/mL, P = 0.01), and significantly increased plasma total antioxidant capacity (TAC) (+ 83.5 +/- 111.7 vs. - 73.4 +/- 195.5 mu mol/L, P < 0.001) and glutathione (GSH) concentrations (+ 60.7 +/- 1402 vs. -15.5 +/- 129.7 mu mol/L, P = 0.03) compared with the placebo. Conclusions: Overall, omega-3 fatty acids supplementation for 12 weeks among subjects with DFU had beneficial effects on parameters of ulcer size, markers of insulin metabolism, serum hs-CRP, plasma TAC and GSH levels. In addition, flaxseed oil omega-3 fatty acids may have played an indirect role in wound healing due to its effects on improved metabolic profiles. (C) 2017 Elsevier Inc. All rights reserved.