Know2eat

Krill oil

Euphausia superba

Fatty Acids & Oils

What krill oil may help with

Ranked by how strong the human evidence is — best supported first.

Best supportedBlood lipid profileLimited evidence· 4 sources

Then, in order

About Krill oil

Oil extracted from Antarctic krill, in which a large share of the EPA and DHA is bound to phospholipids rather than triglycerides. It also contains the carotenoid astaxanthin, which gives it its red colour.

Krill oil is marketed on bioavailability, and the phospholipid argument is biologically reasonable, but the practical problem is concentration: krill oil typically contains far less EPA and DHA per gram than fish oil, so a 1,000 mg krill capsule may supply only 120–180 mg of EPA+DHA against 300 mg from an equivalent fish oil softgel. Head-to-head absorption studies have generally found krill phospholipid omega-3 to be at least as well absorbed per milligram of EPA+DHA, and sometimes better, but "better absorbed" does not compensate for "there is less of it" — and krill oil costs considerably more per milligram of the fatty acids the evidence is actually about.

Sold as
Softgel, Liquid, Combined krill and fish oil blend
Standardised to
Stated as mg EPA and DHA, plus phospholipid percentage and astaxanthin content — a product without this marker may not resemble what was studied.
Also known as
Euphausia superba oil, Antarctic krill oil, Phospholipid omega-3

Regulation: Sold as a dietary supplement in the US with no pre-market efficacy or safety review. Antarctic krill fishing is managed under the CCAMLR convention, and sustainability claims usually rest on that certification rather than on any product property.

What the research used

The amounts, forms and durations published trials of Krill oil actually administered.

These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.

  • Studied for Blood lipid trials

    1–3 g

    Limited

    Krill oil daily, supplying roughly 120–600 mg EPA+DHA · 4–12 weeks

    Trials usually report the krill oil dose rather than the EPA+DHA dose, which makes comparison with fish oil trials difficult and flatters krill oil. Several of these trials were funded by krill oil manufacturers.

  • Studied for Omega-3 index and absorption comparisons

    0.6–1.5 g

    Limited

    EPA+DHA from krill phospholipids · 4 weeks

    Crossover studies matching EPA+DHA milligram for milligram against fish oil report similar or modestly higher incorporation into red blood cell membranes from krill. Matched-dose studies are far less common than unmatched ones.

This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.

When it was taken

Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.

None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.

  • With food

    Not enough

    Phospholipid-bound omega-3 is less dependent on dietary fat and pancreatic lipase than an ethyl ester is, so the food effect is probably smaller. It has not been directly compared, and krill oil is still usually taken with a meal for tolerability.

    Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.

The evidence in depth

Best supported: Limited

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.

Blood lipid profile

Heart Health
Limited evidence

Trials report triglyceride reductions with krill oil, but they are smaller than fish oil trials achieve because the EPA+DHA doses delivered are much lower. Meta-analyses that convert to EPA+DHA rather than oil weight find nothing that suggests krill omega-3 does anything a matched dose of fish oil would not.

Limited evidence. Early human work, or mostly lab and animal research.

View the 4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Joint comfort

Joint Health
Limited evidence

A small number of manufacturer-funded trials report reduced knee pain and stiffness with krill oil over 4–6 months. Independent replication is limited and the effect sizes rest on self-reported pain scores, which respond strongly to placebo.

Limited evidence. Early human work, or mostly lab and animal research.

View the 3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Inflammatory markers

Inflammation
Not enough evidence

There is not enough human research to separate any anti-inflammatory effect of krill oil from the effect of the EPA and DHA it contains. Astaxanthin is often credited in marketing, but the amounts present are small and have not been shown to contribute.

Not enough evidence. Not enough human research to say anything useful yet.

View the 4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Things to know

Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.

  • Allergy

    Crustacean allergen

    Krill are crustaceans and krill oil can contain tropomyosin and other shellfish allergens. Anyone with a shellfish or crustacean allergy should avoid it — this is not a theoretical concern, and it is the single clearest reason to choose fish or algal oil instead.

  • Interaction

    Bleeding risk with anticoagulants and antiplatelets

    Interacts withWarfarin, direct oral anticoagulants, aspirin, clopidogrel

    Krill oil delivers the same EPA and DHA that lengthen bleeding time, and the same caution applies before surgery and alongside warfarin, direct oral anticoagulants or antiplatelet drugs.

  • Worth knowing

    Low EPA+DHA per capsule

    Because krill oil is dilute in the fatty acids the research is about, reaching a trial-level dose of EPA+DHA requires a large number of expensive capsules. Comparing products on EPA+DHA per serving rather than on oil weight usually changes the picture entirely.

  • Worth knowing

    Oxidation and fluoride from shell material

    Krill oil oxidises like other marine oils. Krill exoskeleton is also unusually high in fluoride, and poorly processed product that carries shell material can contribute meaningful fluoride, which is why processing method matters.

Evidence ratings on this page: 2 limited evidence, 1 not enough evidence.

Supplements are sold in the US without pre-market review of efficacy or safety. Nothing on this page is a recommendation to take Krill oil, or a dose to follow.