Omega-3 is one of the few supplements with genuinely well-established, authorised roles — but the marketing around it is still full of overreach. This guide covers omega-3 for heart and brain health honestly: what EPA and DHA actually do, what the authorised claims are, and how to choose a fish oil that delivers a real dose rather than a token one.
For transparency: the authorised claims for omega-3 are specific. EPA and DHA contribute to the normal function of the heart; DHA contributes to the maintenance of normal brain function and normal vision. These claims apply at defined daily intakes. We stick to them throughout and don't stray into disease-prevention territory.
EPA and DHA: the two that matter
"Omega-3" is an umbrella term, but the two forms that carry authorised health claims are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), both found in oily fish. A third, ALA, comes from plants but converts poorly. When you're choosing a supplement for heart or brain support, it's the EPA and DHA content that counts — not the total fish oil weight, which can be misleading.
Omega-3 and the heart
EPA and DHA contribute to the normal function of the heart, with a beneficial effect obtained at a daily intake of 250mg of EPA and DHA combined. That's the authorised claim, and it's a meaningful one — the heart role is the most established reason people take omega-3. Our High-Strength Omega-3 Fish Oil delivers well above that 250mg threshold per serving, so the heart claim is comfortably met. More on this in our piece on the best fish oil for heart health.
Omega-3 and the brain
DHA specifically contributes to the maintenance of normal brain function (again at a 250mg daily intake of DHA). DHA is a major structural fat in the brain, which is why it's the form associated with cognitive support. It's important to be precise here: the authorised claim is maintenance of normal brain function — not improving memory, treating decline, or boosting intelligence. We explore the honest version of this in omega-3 and brain fog.
Omega-3 and vision
DHA also contributes to the maintenance of normal vision, at the same 250mg daily intake. This is a genuine, lesser-known authorised claim — and the reason omega-3 comes up in conversations about eye comfort and dryness, which we cover in omega-3 for dry eyes.
How to choose a fish oil that actually delivers
- Look at EPA and DHA, not total oil — a 1,000mg fish oil might contain only 300mg of actual EPA/DHA. The active numbers are what matter.
- Meet the 250mg threshold comfortably — that's the level the authorised claims are built on; a serious dose clears it with room to spare.
- Check purity — fish oil should be tested for heavy metals and oxidation. Ours is tested for purity and heavy metals at a GMP-certified facility.
- Form and freshness — a quality softgel with no rancid "fishy" aftertaste is a good practical sign.
- Be sceptical of disease claims — omega-3 supports normal heart, brain and vision function; any product claiming to treat or prevent disease is overstepping.
Where our fish oil sits
Our High-Strength Omega-3 Fish Oil is built around the EPA and DHA numbers that matter — 1,040mg EPA and 692mg DHA per serving — comfortably clearing the 250mg threshold for the heart, brain and vision claims, in a clean softgel tested for purity.
Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. If you are pregnant, breastfeeding, taking medication or managing a medical condition, speak to your GP or pharmacist before starting a new supplement. Contains fish. Signed, Dr. Miron, Founder of Pure Vitamins UK.
