Krill Oil
Useful mainly for people wanting a well-absorbed, low-burp omega-3 source to raise omega-3 status.
Quick decision guide
May help most
people wanting a well-absorbed, low-burp omega-3 source to raise omega-3 status
Common dosing range
500–2,000 mg/day (≈100–600 mg EPA+DHA)
When to expect effects
Weeks
Watch out for
Avoid with shellfish allergy; mild bleeding-time effect at high doses
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.
Is it worth it for you?
Use this as a quick fit check, not a diagnosis.
Worth considering if…
Probably skip if…
Evidence at a glance
| Goal | Effect | Best fit | Time |
|---|---|---|---|
raising omega-3 index Good Evidence | Meaningful rise in omega-3 index | people with low omega-3 intake wanting to raise EPA/DHA status | Weeks |
triglyceride reduction Limited Evidence | Small reductions | people with mildly elevated triglycerides | Weeks |
premenstrual and menstrual pain Limited Evidence | Uncertain | women with premenstrual symptoms or dysmenorrhea | Across cycles |
joint comfort in osteoarthritis Limited Evidence | Small | people with mild knee osteoarthritis symptoms | Weeks |
raising omega-3 index
- Effect
- Meaningful rise in omega-3 index
- Best fit
- people with low omega-3 intake wanting to raise EPA/DHA status
- Time
- Weeks
triglyceride reduction
- Effect
- Small reductions
- Best fit
- people with mildly elevated triglycerides
- Time
- Weeks
premenstrual and menstrual pain
- Effect
- Uncertain
- Best fit
- women with premenstrual symptoms or dysmenorrhea
- Time
- Across cycles
joint comfort in osteoarthritis
- Effect
- Small
- Best fit
- people with mild knee osteoarthritis symptoms
- Time
- Weeks
Evidence for 4 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
raising omega-3 index
Biomarker supportKrill oil delivers EPA and DHA largely in phospholipid form and reliably raises the blood omega-3 index in trials, sometimes efficiently relative to dose. Raising the omega-3 index is a biomarker change, not in itself a clinical outcome. Whether krill oil reduces cardiovascular events has not been demonstrated.
Bottom line: Krill oil reliably raises omega-3 status, but that is a marker rather than proven clinical benefit.
triglyceride reduction
Biomarker supportOmega-3s lower triglycerides, and small krill oil trials report modest reductions, though typical krill doses supply less EPA+DHA than triglyceride-lowering fish oil regimens. This is a lipid-marker effect. High-dose fish oil has stronger triglyceride evidence.
Bottom line: May modestly lower triglycerides, but doses are usually small and the effect is a biomarker.
premenstrual and menstrual pain
Supplement benefitA few small studies suggest krill oil may reduce premenstrual symptoms and menstrual pain, plausibly via omega-3 effects on inflammatory signaling. The evidence is limited and not well replicated.
Bottom line: Preliminary, limited evidence for easing premenstrual and menstrual pain.
joint comfort in osteoarthritis
Supplement benefitSome small trials report modest improvements in joint pain or stiffness with krill oil, consistent with omega-3 anti-inflammatory effects. Trials are small and short, so confidence is low.
Bottom line: May give small joint-comfort benefits on limited evidence.
How it works
How to take it
What to track
Safety
Know the common side effects, key cautions, and who should avoid it.
Common side effects
Who should avoid it
- people with shellfish allergy
- people on anticoagulants at high doses without medical advice
Pregnancy & breastfeeding
Omega-3s are generally used in pregnancy, but discuss krill oil specifically with a provider; avoid with shellfish allergy.
Interactions
may increase bleeding risk at high doses
may modestly lower blood pressure
Choosing a product
What to look for on the label — and what to be skeptical of.
Look for…
Be skeptical of…
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.
References by claim
raising omega-3 index
triglyceride reduction
premenstrual and menstrual pain
Sampalis et al., 2003 — PubMed (2003) link
Track Krill Oil with Pilora
Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.
Coming to App StoreDisclaimer: 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.