Krill Oil

fatcastor oil

What is it

Krill oil is extracted from small shrimp-like crustaceans (Antarctic krill, Euphausia superba). It provides EPA and DHA omega-3 fatty acids primarily in phospholipid form, plus the antioxidant astaxanthin.

How it works

Most of the omega-3 fatty acids in krill oil are bound to phospholipids (phosphatidylcholine), unlike fish oil where they are bound to triglycerides. The phospholipid form may integrate into cell membranes more readily and is more water-dispersible, which may improve absorption at lower doses. Once absorbed, the EPA and DHA do the same things as omega-3s from any source. Krill oil naturally contains astaxanthin, a potent antioxidant that protects the oil from oxidation and may have independent biological effects. The amount per dose is typically too small to provide standalone antioxidant benefits comparable to dedicated astaxanthin supplements.

Evidence for 5 uses

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Raising omega-3 index

Grade B

Good evidence

Krill oil effectively raises EPA+DHA in blood and red blood cell membranes. Some research suggests comparable or slightly better absorption per mg of EPA+DHA than fish oil triglycerides.

Triglyceride reduction

Grade C

Moderate evidence

Modest triglyceride reductions in trials, similar to expectations based on the EPA+DHA dose delivered. Less data than for fish oil.

PMS and menstrual pain

Grade C

Moderate evidence

A few trials suggest krill oil may reduce PMS symptoms and menstrual pain compared to placebo or fish oil. Evidence base is limited.

Joint comfort in osteoarthritis

Grade C

Moderate evidence

Some trials show modest improvement in joint pain and stiffness. Effect size is small.

LDL cholesterol

Grade C

Moderate evidence

Some trials show modest LDL reduction, possibly through the phospholipid component. Effect is inconsistent.

Dosage

Common doses are 500 to 2,000 mg of krill oil per day, providing roughly 100 to 600 mg of EPA+DHA. Higher doses provide more omega-3s but cost considerably more than equivalent fish oil. The FDA considers up to 3 g/day of combined EPA+DHA from any source generally safe.

When and how to take it

Take with a meal containing fat for best absorption, though the phospholipid form may absorb somewhat better without food than triglyceride fish oil. Many users report less burping than fish oil. Daily dosing maintains omega-3 status.

Safety

Krill oil is well tolerated, often with fewer fishy burps than standard fish oil. People with shellfish allergies should not take krill oil. As with other omega-3s, high doses may modestly increase bleeding time. Krill is harvested from the Southern Ocean and harvest sustainability is a consideration — choose certified sustainable products if this matters to you.

Who should be cautious

People with shellfish allergies should not take krill oil — use fish oil or algal oil instead. People on anticoagulants or scheduled for surgery should discuss high-dose use with their doctor.

Interactions

Same as other omega-3 sources. May increase bleeding risk with anticoagulants and antiplatelet drugs at high doses. May lower blood pressure modestly. The astaxanthin content is unlikely to cause significant interactions at typical doses.

Frequently asked questions

Is krill oil better than fish oil?⌄

Per gram of EPA+DHA, krill oil may absorb somewhat better and burps less. But it costs significantly more, so for high doses fish oil is more practical.

Can I take krill oil if I am allergic to shellfish?⌄

No. Krill is a crustacean. Use fish oil or algal oil instead.

How much krill oil should I take?⌄

Most people take 500 to 1,500 mg per day. Check the EPA+DHA content on the label, since this varies.

Is astaxanthin in krill oil meaningful?⌄

It provides antioxidant protection for the oil itself. Standalone astaxanthin supplements typically provide much more if you want astaxanthin specifically.

Is krill oil sustainable?⌄

Antarctic krill harvesting is regulated and some products carry sustainability certifications (such as MSC). If sustainability matters to you, look for certified products.

Track Krill Oil with Pilora

Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.

Coming to App Store

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you're pregnant, breastfeeding, on medications, or managing a chronic condition.