Efficacy of flaxseed oil compared with fish oil supplementation in the treatment of coronary heart disease: a retrospective study

BACKGROUND: Many studies have demonstrated the beneficial effects of omega‐3 fatty acids in animal models and human diseases. Compared with commonly used fish oil, flaxseed oil has better palatability. However, the relative efficacy of the two types of oil on the cardiovascular health of type 2 diabetes mellitus (T2DM) patients with coronary heart disease (CHD) is unclear. METHODS: This was a retrospective study based on the prospectively maintained database of Hubei Provincial Hospital of Traditional Chinese Medicine. Patients meeting the inclusion criteria were enrolled and then divided into two groups: the flaxseed oil group received 1,000 mg flaxseed oil, which contains 400 mg of α-Linolenic acid, as their omega‐3 fatty acid source; the fish oil group received 1,000 mg of fish oil, which contains 250 mg of eicosapentaenoic acid and 150 mg of docosahexaenoic acid. The primary outcome was cardiovascular risk biomarker changes between the two groups. P values less than 0.05 were considered statistically significant. RESULTS: A total of 120 patients were enrolled in the present study: 60 in the flaxseed oil group and 60 in the fish oil group. After a median follow-up of 10.0 weeks (95% CI: 8.4–11.6 weeks), flaxseed oil was found to be significantly better at reducing serum insulin levels and high‐sensitivity C‐reactive protein (hs‐CRP) levels than fish oil (P=0.03 and P=0.02, respectively). The effects of flaxseed oil and fish oil on homeostatic model assessment for insulin resistance (HOMA-IR), fasting plasma glucose (FPG); body weight, and body mass index (BMI) were found to be similar. Moreover, patients who received flaxseed oil tended to have a better overall survival than those who received fish oil, although the difference was not statistically significant (P=0.067). CONCLUSIONS: Compared with fish oil, flaxseed oil was more effective in reducing serum insulin levels and hs‐CRP levels for T2DM patients with CHD. For these patients, flaxseed oil might become a novel choice.