What are omega-3 fatty acids?
Omega-3s are a family of polyunsaturated fats that your body cannot produce on its own — meaning you must get them from food or supplements. There are three main types, but two of them are what the research focuses on:
EPA (eicosapentaenoic acid) — primarily anti-inflammatory. Found in fatty fish and fish oil. Most studied for heart health, mood and joint function.
DHA (docosahexaenoic acid) — primarily structural. It literally makes up a large portion of your brain tissue and the retina of your eye. Critical for cognitive function and vision.
ALA (alpha-linolenic acid) — found in plant sources like flaxseed and walnuts. Your body can convert ALA to EPA and DHA, but the conversion rate is very low — typically less than 5–10%. This is why plant-based omega-3 sources are generally insufficient on their own.
Studies estimate that over 70% of the global population does not consume adequate EPA and DHA. This is one of the most widespread nutritional deficiencies worldwide — affecting people in countries where fish consumption is low and processed food consumption is high.
How omega-3s work inside your body
Omega-3s are incorporated into your cell membranes
When you consume EPA and DHA, they become part of the phospholipid bilayer of virtually every cell in your body. This changes how fluid and flexible your cell membranes are — affecting how well they communicate and respond to signals.
They regulate inflammation at the molecular level
EPA and DHA are precursors to compounds called resolvins and protectins — molecules that actively resolve inflammation. They compete with omega-6 fatty acids (pro-inflammatory) for the same enzymes, effectively reducing the inflammatory response in tissues.
DHA is physically built into brain tissue
DHA makes up about 30–40% of the total fat in the brain and retina. It's not just a signaling molecule — it's a structural component. Low DHA is associated with reduced cognitive performance, depression, and age-related cognitive decline.
They influence cardiovascular function
EPA and DHA reduce blood triglyceride levels, decrease platelet aggregation (blood clotting tendency), and modestly lower resting heart rate. These effects combine to reduce cardiovascular disease risk — one of the most replicated findings in nutritional science.
What the research actually shows
Heart health
Strong evidence for reducing triglycerides (by 15–30%) and lowering cardiovascular disease risk at higher doses.
Brain & mood
DHA is essential for cognitive function. EPA has consistent evidence for reducing symptoms of depression, particularly at doses of 1–2g EPA/day.
Joints & recovery
Anti-inflammatory effects reduce joint pain and morning stiffness. Useful for both athletes and people with arthritis.
Eye health
DHA is a structural component of the retina. Adequate intake is associated with reduced risk of age-related macular degeneration.
Omega-3 research is strong for cardiovascular and brain health. It is more mixed for direct muscle-building effects — don't take omega-3 expecting gym performance gains. Take it for general health and long-term wellbeing.
How much do you need?
Best omega-3 products — available globally
Available on iHerb, shipping to 180+ countries. Selected for EPA+DHA concentration, form (triglyceride preferred), freshness standards, and third-party testing.
Ultra Omega-3
High-concentration EPA+DHA (690mg EPA / 310mg DHA per softgel), triglyceride form, IFOS certified for purity. Excellent value for quality.
Fish Oil 1200mg
Reliable brand, consistent quality, affordable price. 360mg EPA+DHA per softgel — take 3 daily for a solid 1g dose.
Algae Omega
EPA+DHA derived from algae — the original source fish get their omega-3 from. Perfect for vegans and vegetarians. Same benefits, no fish.