The Truth About Omega-3s: Dose, Form, and What the Evidence Actually Shows

Omega-3s had a decade of enthusiasm, followed by disappointing clinical trials in the early 2010s that led many physicians to dismiss them. Then in 2018, the REDUCE-IT trial changed the conversation: high-dose EPA (4g/day) reduced cardiovascular events by 25% in high-risk patients. The lesson wasn't that omega-3s don't work. The lesson was that dose and form matter enormously, and most people take far too little of the wrong type.

EPA vs. DHA: Two Different Jobs

EPA (eicosapentaenoic acid) is primarily anti-inflammatory and cardiovascular-protective. DHA (docosahexaenoic acid) is concentrated in brain and retinal tissue, critical for cognitive function and visual health. Most fish oil products combine both, appropriate for general health, but therapeutic use often emphasizes one or the other based on the goal.

The Test Nobody Runs

The Omega-3 Index measures the percentage of EPA + DHA in your red blood cell membranes. Below 4% is high-risk; above 8% is protective. Most Americans test at 4-5%. To reach 8%+, you need at least 2-3g of combined EPA + DHA daily, more than twice what most single-capsule supplements provide.

Fish Oil vs. Algal Oil

Fish don't actually make EPA and DHA, they accumulate it by eating algae. Algal oil goes straight to the source and is preferred for those avoiding fish products or concerned about heavy metal contamination. Bioavailability is comparable to fish oil and quality is generally more consistent.