China: Regular consumption of fish oil supplements and elevated levels of omega-3 polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA), are linked to reduced vascular complication risks in individuals diagnosed with type 2 diabetes (T2D), a recent study has found.
The findings, published in The Journal of Clinical Endocrinology & Metabolism, suggest that the positive correlations were partly explained by enhancements in lipid profile and reduction in inflammation biomarkers.

Fish oils, abundant in omega-3 polyunsaturated fatty acids (PUFAs), are recognized for their vascular health benefits in the general population. However, studies investigating their effects on individuals with type 2 diabetes (T2D), who face an elevated risk of vascular disease, are limited.
To fill this knowledge gap, Gang Liu, Huazhong University of Science and Technology, Wuhan, China, and colleagues aimed to evaluate associations of fish oil supplementation and plasma omega-3 PUFAs with risks of macrovascular and microvascular complications among people with type 2 diabetes. They further explored the potential mediating role of metabolism-related biomarkers.
This study comprised 20,338 participants with type 2 diabetes from UK Biobank. Participants' use of regular fish oil supplementation was assessed through an electronic questionnaire administered at baseline from 2006 to 2010. Blood samples collected between 2019 and 2020 were analyzed for omega-3 fatty acids.
The study focused on diabetic macrovascular complications (including coronary heart disease, heart failure, peripheral artery disease, and stroke) and microvascular complications (such as diabetic kidney disease, diabetic retinopathy, and diabetic neuropathy). Biomarkers associated with cardiovascular disease were assessed in the blood samples obtained during recruitment.
The study revealed the following findings:
During 13.2 years of follow-up, 5,396 people developed macrovascular complications, and 4,868 people developed microvascular complications.
After multivariable adjustment, hazard ratios (HRs) for patients with fish oil were 0.90 for composite macrovascular complications, 0.91 for coronary heart disease (CHD), 0.72 for peripheral artery disease, and 0.89 for composite microvascular complications, 0.87 for diabetic kidney disease, and 0.88 for diabetic retinopathy.
Higher n-3 PUFA levels, especially docosahexaenoic acid (DHA), were associated with lower risks of macrovascular and microvascular complications. Comparing extreme quartiles of plasma DHA, the HRs were 0.68 for composite macrovascular complications, 0.63 for CHD, and 0.59 for diabetic neuropathy.
Biomarkers, including lipid profile and inflammation, collectively explained 54.4% and 63.1% of associations of plasma DHA with risks of composite macrovascular complications and CHD.
"Regular use of fish oil supplements and elevated plasma levels of omega-3 PUFAs, particularly DHA, were linked to reduced risks of macrovascular and microvascular complications in individuals with type 2 diabetes. The beneficial effects observed were partly attributed to improvements in lipid profile and reduction in inflammation biomarkers," the researchers concluded.
Reference:
Tian, S., Guo, T., Qian, F., Qiu, Z., Lu, Q., Li, R., Zhu, K., Li, L., Yu, H., Li, R., Ou, Y., Pan, A., & Liu, G. Fish Oil, Plasma n-3 PUFAs, and Risk of Macro- and Microvascular Complications among Individuals with Type 2 Diabetes. The Journal of Clinical Endocrinology & Metabolism. https://doi.org/10.1210/clinem/dgae482