By: Dr. Abdulwahab. A. Arrazaghi. MBBCH, FDABIM, FRCPC
What are Omega-3 Fatty Acids?
Omega-3 fatty acids are essential polyunsaturated fats critical for maintaining cardiovascular health. The three main types are:
EPA (eicosapentaenoic acid): Found in marine sources, reduces inflammation and triglycerides.
DHA (docosahexaenoic acid): Supports heart function and brain health.
ALA (alpha-linolenic acid): Found in plant sources and converted to EPA and DHA in small amounts.
How Omega-3 Fatty Acids Impact Heart Health
Triglyceride Reduction: Omega-3s reduce serum triglycerides by up to 30%.
Blood Pressure Control: Regular intake lowers both systolic and diastolic blood pressure.
Anti-Inflammatory Effects: Decrease levels of inflammatory markers such as C-reactive protein (CRP).
Arrhythmia Prevention: Stabilizes heart rhythm and reduces the risk of sudden cardiac death.
Plaque Stabilization: Improves arterial function and reduces atherosclerosis progression.
Clinical Evidence for Omega-3 and Heart Health
1. Reduction in Cardiovascular Events
The GISSI-Prevenzione trial demonstrated a 20% reduction in all-cause mortality and a 45% reduction in sudden cardiac death among post-myocardial infarction patients taking omega-3 supplements (1 g/day EPA/DHA). Reference: Marchioli R, et al. Lancet, 1999.
2. Triglyceride Reduction
A meta-analysis of 47 RCTs reported a significant triglyceride-lowering effect, particularly at higher doses (2–4 g/day). Reference: Balk EM, et al. Journal of Clinical Lipidology, 2006.
3. Arrhythmia Prevention
The REDUCE-IT trial showed that 4 g/day of EPA (icosapent ethyl) significantly reduced major adverse cardiovascular events (MACE) in high-risk patients. Reference: Bhatt DL, et al. New England Journal of Medicine, 2019.
4. Stroke Risk Reduction
A systematic review found a 12% reduction in stroke risk with higher omega-3 intake. Reference: He K, et al. Stroke, 2004.
Recommended Dosage
General Population: 1–2 g/day of combined EPA and DHA.
Patients with High Triglycerides: 2–4 g/day under medical supervision.
Sources of Omega-3 Fatty Acids
Marine Sources: Fatty fish (salmon, mackerel, sardines).
Plant Sources: Flaxseeds, chia seeds, walnuts (ALA).
Supplements: Fish oil, krill oil, or algal oil (for vegetarians).
Safety and Precautions
Side Effects: May cause gastrointestinal upset or mild fishy aftertaste.
Drug Interactions: Can increase bleeding risk, particularly in patients on anticoagulants.
Purity Concerns: Ensure supplements are third-party tested for heavy metals.
Summary
Omega-3 fatty acids are among the most well-studied nutrients for heart health. Their ability to reduce triglycerides, stabilize heart rhythm, and prevent adverse cardiovascular events makes them a critical part of any heart-healthy regimen.
References;
Nicholls SJ, et al. "Effect of Icosapent Ethyl on Progression of Coronary Atherosclerosis." Circulation, 2020; 141(9):604–607. DOI: 10.1161/CIRCULATIONAHA.119.044440.
Rauch B, et al. "OmegA Trial Results." European Heart Journal, 2010; 31(14):1617–1623. DOI: 10.1093/eurheartj/ehq141.
Grenon SM, et al. "Effects of Omega-3 Supplementation in PAD." Journal of Vascular Surgery, 2013; 58(5):1283–1290. DOI: 10.1016/j.jvs.2013.03.008.
Bhatt DL, et al. "Cardiovascular Risk Reduction with Icosapent Ethyl." New England Journal of Medicine, 2019; 380(1):11–22. DOI: 10.1056/NEJMoa1812792.
He K, et al. "Fish Consumption and Risk of Stroke in Men and Women." Stroke, 2004; 35(7):1538–1542. DOI: 10.1161/01.STR.0000130856.96316.ea.
Mozaffarian D, et al. "Fish Intake and Risk of Stroke in US Adults." Circulation, 2005; 111(21):2805–2810. DOI: 10.1161/CIRCULATIONAHA.104.504459.
Dangour AD, et al. "Omega-3 Fats for Prevention of Cognitive Decline." Neurology, 2010; 75(10):963–970. DOI: 10.1212/WNL.0b013e3181f5cbd7.
Minihane AM, et al. "Genetic Influence on Omega-3 Benefits." Nutrients, 2016; 8(10):583. DOI: 10.3390/nu8100583.