NutriDex

The Supplement Research Compendium
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Krill Oil

Euphausia superba

Phospholipid-bound omega-3s that modestly lower triglycerides.

Moderate evidence 🫀Heart & Metabolic

✚ Updated · How we grade evidence

Evidence tier
Moderate
Research weight
Citations
7 verified / 7
Classification
Heart & Metabolic
❝
What the evidence says. Graded moderate: meta-analyses of small RCTs consistently show real but modest improvements in triglycerides, LDL and HDL, yet no trial has proven reduced heart attacks or strokes, doses are low, and the once-promoted joint-pain benefit failed in the largest RCT. (Moderate evidence: Several controlled trials; effects real but modest or context-dependent.)

What is Krill Oil?

Krill Oil (Euphausia superba) is a heart and metabolic supplement used for lower triglycerides. NutriDex grades the human evidence as Moderate. Krill oil is an omega-3 supplement from Antarctic krill in which EPA and DHA are bound mainly to phospholipids rather than triglycerides (as in fish oil), which may modestly improve absorption. Pooled RCT data show real but small lipid changes: triglycerides fall about 14 mg/dL and LDL about 15 mg/dL, while HDL rises about 7 mg/dL. A prescription-grade krill formulation cut triglycerides ~26% in severe hypertriglyceridemia. However, no trial has shown krill oil prevents heart attacks, strokes or death, and typical over-the-counter capsules deliver fairly low EPA+DHA. Once marketed for joint pain, an early 6-month RCT found modest knee-osteoarthritis relief, but a larger 2024 JAMA trial found no benefit over placebo. Krill oil is a reasonable, generally well-tolerated omega-3 source, but expect lipid nudges, not dramatic outcomes.

Purported Benefits

✓Lower triglycerides
✓Lower LDL cholesterol
✓Raise HDL cholesterol
✓Omega-3 (EPA/DHA) source

Evidence by outcome

The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.

OutcomeEvidenceEffectStudies
Lower triglyceridesTwo meta-analyses show ~14 mg/dL drop; prescription-grade cut TG ~26% in severe hypertriglyceridemia. Strong ↑ benefit · small 3
Lower LDL cholesterolMeta-analyses report LDL drops ~15 mg/dL, but magnitude is modest and trials vary in dose/quality. Moderate ↑ benefit · small 2
Raise HDL cholesterol7-RCT meta-analysis found HDL rise ~7 mg/dL; small effect not shown to translate to outcomes. Moderate ↑ benefit · small 1
Relieve knee osteoarthritis pain6-mo RCT found modest pain relief, but a larger 2024 RCT found no benefit over placebo at 24 weeks. Mixed ↔ mixed · small 2
Higher omega-3 (EPA/DHA) bioavailability vs fish oilOne crossover found ~50% higher EPA/DHA uptake; another saw higher incorporation but non-significant due to variance. Preliminary ↔ mixed · small 2

Dosing & Compounds

Typical Dose
1–4 g/day of krill oil providing roughly 200–600 mg combined EPA+DHA; prescription-strength formulations deliver more.
Active Compounds
EPA & DHA (phospholipid-bound)AstaxanthinCholine

Safety & Cautions

Generally well tolerated; the main side effects are fishy aftertaste, burping, and mild GI upset. Avoid if you are allergic to shellfish, krill or other crustaceans. Like other omega-3s, krill oil can mildly thin the blood, so use caution and consult a clinician if you take anticoagulants or antiplatelets (warfarin, DOACs, aspirin, clopidogrel) or are scheduled for surgery. Discuss with your doctor before use if pregnant or breastfeeding, as safety data are limited. Educational only — always check with your doctor or pharmacist before combining Krill Oil with any medicine.

Krill Oil drug interactions

Known or theoretical interactions between Krill Oil and common medications — educational, not exhaustive. Always check with your doctor or pharmacist before combining Krill Oil with any medicine.

Monitor
Blood thinners (warfarin, DOACs)
High-dose krill oil may slightly add to bleeding risk alongside blood thinners; watch for easy bruising.
Omega-3 (EPA/DHA) reduce platelet aggregation and have mild antithrombotic action that can compound anticoagulants. NIH ODS — Omega-3 Fatty Acids
Monitor
Antiplatelet drugs (aspirin, clopidogrel)
Krill oil with aspirin or clopidogrel may modestly increase bleeding tendency at high doses.
EPA/DHA dampen platelet aggregation, adding to the antiplatelet effect of these drugs. NIH ODS — Omega-3 Fatty Acids

Key Studies

Meta-analysis Sun 2023 ✓ PubMed
Updated meta-analysis (14 RCTs, 1458 people): significant drops in total cholesterol, LDL and triglycerides; no effect on BP, glucose or inflammation.
Meta-analysis Ursoniu 2017 ✓ PubMed
Meta-analysis (7 RCTs, 662 people): krill oil cut LDL ~15.5 mg/dL and triglycerides ~14 mg/dL and raised HDL ~6.7 mg/dL.
RCT Wang 2024 ✓ PubMed
Larger RCT (n=262): 2 g/day krill oil did NOT improve knee pain over 24 weeks (mean difference 0.3 on VAS; P=0.94).
RCT Tirtawijaya 2022 ✓ PubMed
RCT pooling 2 trials (~520 patients): prescription krill oil lowered triglycerides 26.0% vs 15.1% placebo in severe hypertriglyceridemia at 12 weeks.
RCT Stonehouse 2022 ✓ PubMed
6-month RCT (n=235): 4 g/day krill oil modestly improved knee pain (-5.2 of 100), stiffness and function in mild-moderate osteoarthritis.
RCT Köhler 2015 ✓ PubMed
Single-dose crossover: 72-h EPA/DHA bioavailability ~50% higher for krill oil (89.1 %×h) than fish oil (59.2 %×h; P=0.003).
RCT Schuchardt 2011 ✓ PubMed
Crossover trial: at equal 1680 mg EPA+DHA, krill oil gave higher plasma phospholipid incorporation than fish oil, but high variance left it non-significant.
7 sources cited · 7 verified Search all studies on PubMed ↗

Common questions about Krill Oil

What is Krill Oil used for?

Krill Oil is most often taken for Lower triglycerides, Lower LDL cholesterol, Raise HDL cholesterol, Omega-3 (EPA/DHA) source. Phospholipid-bound omega-3s that modestly lower triglycerides.

Does Krill Oil work — what does the evidence say?

Moderate evidence. Several controlled trials; effects real but modest or context-dependent. Krill oil is an omega-3 supplement from Antarctic krill in which EPA and DHA are bound mainly to phospholipids rather than triglycerides (as in fish oil), which may modestly improve absorption. Pooled RCT data show real but small lipid changes: triglycerides fall about 14 mg/dL and LDL about 15 mg/dL, while HDL rises about 7 mg/dL. A prescription-grade krill formulation cut triglycerides ~26% in severe hypertriglyceridemia. However, no trial has shown krill oil prevents heart attacks, strokes or death, and typical over-the-counter capsules deliver fairly low EPA+DHA. Once marketed for joint pain, an early 6-month RCT found modest knee-osteoarthritis relief, but a larger 2024 JAMA trial found no benefit over placebo. Krill oil is a reasonable, generally well-tolerated omega-3 source, but expect lipid nudges, not dramatic outcomes.

What is the typical dose of Krill Oil?

1–4 g/day of krill oil providing roughly 200–600 mg combined EPA+DHA; prescription-strength formulations deliver more.

Is Krill Oil safe? Any cautions or side effects?

Generally well tolerated; the main side effects are fishy aftertaste, burping, and mild GI upset. Avoid if you are allergic to shellfish, krill or other crustaceans. Like other omega-3s, krill oil can mildly thin the blood, so use caution and consult a clinician if you take anticoagulants or antiplatelets (warfarin, DOACs, aspirin, clopidogrel) or are scheduled for surgery. Discuss with your doctor before use if pregnant or breastfeeding, as safety data are limited.

How many studies support Krill Oil?

NutriDex cites 7 sources for Krill Oil, graded "Moderate".

Does Krill Oil interact with any medications?

Yes — known or theoretical interactions include: Blood thinners (warfarin, DOACs) (monitor), Antiplatelet drugs (aspirin, clopidogrel) (monitor). This is educational and not exhaustive; always check with your doctor or pharmacist before combining Krill Oil with any medicine.

Cite this page
APA

Peh, D. (2026). Krill Oil (Euphausia superba): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 26 Jun 2026, from https://nutridex.info/s/krill-oil

BibTeX
@misc{nutridex_krill_oil,
  author       = {Peh, Daryl},
  title        = {Krill Oil (Euphausia superba): Benefits, Dosage, Side Effects \& Evidence},
  year         = {2026},
  howpublished = {NutriDex --- The Supplement Research Compendium},
  url          = {https://nutridex.info/s/krill-oil},
  note         = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-06-26}
}

For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.

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