Effects of n-3 Fatty Acid Supplements on Glycemic Traits in Chinese Type 2 Diabetic Patients: A Double-Blind Randomized Controlled Trial

Mol Nutr Food Res. 2016 Oct;60(10):2176-2184. doi: 10.1002/mnfr.201600230. Epub 2016 Jul 12.


Scope: To investigate the effects of n-3 fatty acid supplements, both marine and plant-based, on glycemic traits in Chinese type 2 diabetes patients.

Method and results: In a double-blind randomized controlled trial, 185 recruited Chinese type 2 diabetes patients were randomized to either fish oil (FO, n = 63), flaxseed oil (FSO, n = 61), or corn oil group (served as control group, n = 61) for 180 days. The patients were asked to take corresponding oil capsules (four capsules/day), which totally provided 2 g/day of eicosapentaenoic acid + docosahexaenoic acid in FO group and 2.5 g/day of alpha-linolenic acid in FSO group. No group × time interaction was observed for homeostatic model assessment of insulin resistance, fasting insulin, or glucose. Significant group × time interaction (P = 0.035) was observed for glycated hemoglobin A1c (HbA1c), with HbA1c decreased in FO group compared with corn oil group (P = 0.037). We also found significant group × time interactions for lipid traits, including LDL cholesterol (P = 0.043), total cholesterol (P = 0.021), total cholesterol/HDL cholesterol (P = 0.009), and triacylglycerol (P = 0.003), with the lipid profiles improved in FO group. No significant effects of FSO on glycemic traits or blood lipids were observed.

Conclusions: Marine n-3 PUFA supplements may improve glycemic control and lipid profiles among Chinese type 2 diabetic patients.

Trial registration: ClinicalTrials.gov NCT01857167.

Keywords: Randomized controlled trial; Type 2 diabetes; n-3 Fatty acids.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Asian Continental Ancestry Group
  • Cholesterol, LDL / blood
  • Corn Oil / pharmacology
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / diet therapy*
  • Dietary Supplements
  • Docosahexaenoic Acids / blood
  • Double-Blind Method
  • Eicosapentaenoic Acid / blood
  • Fatty Acids, Omega-3 / pharmacology*
  • Female
  • Fish Oils / pharmacology*
  • Glycated Hemoglobin A / metabolism
  • Humans
  • Linseed Oil / pharmacology*
  • Male
  • Middle Aged


  • Cholesterol, LDL
  • Fatty Acids, Omega-3
  • Fish Oils
  • Glycated Hemoglobin A
  • Docosahexaenoic Acids
  • Linseed Oil
  • Corn Oil
  • Eicosapentaenoic Acid

Associated data

  • ClinicalTrials.gov/NCT01857167