Omega-3 Fatty Acids: EPA vs. DHA — What the Research Actually Shows

What Are Omega-3 Fatty Acids?

Omega-3s are polyunsaturated essential fats — your body cannot make them, so you must obtain them through diet or supplements. The three main types:

• ALA (alpha-linolenic acid): Found in flaxseed, walnuts. Poorly converted to EPA/DHA (~5–10%)
• EPA (eicosapentaenoic acid): Anti-inflammatory, cardiovascular, mood support
• DHA (docosahexaenoic acid): Brain structure, retinal health, fetal development

Evidence-Based Benefits

Cardiovascular Health: High-dose EPA (Vascepa/icosapentaenoic acid, 4g/day) reduced major cardiovascular events by 25% in the REDUCE-IT trial. Standard doses lower triglycerides by 15–30%.

Brain & Mood: DHA is the dominant structural fat in the brain (~30% of cerebral cortex). EPA has demonstrated antidepressant effects in RCTs — the EPA:DHA ratio matters here (high-EPA formulas outperform mixed products in depression studies).

Inflammation: EPA and DHA produce resolvins and protectins — molecules that actively resolve inflammation, not just suppress it.

Eye Health: DHA is concentrated in the retina. Supplementation slows age-related macular degeneration progression.

Dosing

| Goal | Dose (combined EPA+DHA) | |------|-------------------------| | General health & maintenance | 1,000–2,000 mg/day | | Triglyceride reduction | 2,000–4,000 mg/day | | Depression / mood support | 1,000–2,000 mg EPA-dominant | | Anti-inflammatory | 2,000–3,000 mg/day |

Quality Matters

Fish oil oxidizes easily. Look for:

• IFOS certified or third-party tested (ConsumerLab, USP)
• Triglyceride (TG) form absorbs 70% better than ethyl ester (EE) form
• Store in the fridge after opening
• Should not smell fishy — rancid oil smells strong and provides no benefit

Pharmacist Safety Note

At doses above 3g/day, omega-3s have a mild blood-thinning effect.

Drug Interactions:

• Warfarin/anticoagulants: Increases bleeding risk at high doses — monitor INR
• Antiplatelet drugs (aspirin, clopidogrel): Additive effect, generally considered safe at standard doses but mention to your doctor
• May slightly lower blood pressure — adjust antihypertensive doses if needed