Home Ingredients Krill Oil
CardiovascularJoint Health

Krill Oil

Euphausia superba
Evidence Level
Moderate
2 Clinical Trials
6 Documented Benefits
3/5 Evidence Score

Krill oil is extracted from Antarctic krill (Euphausia superba) — small shrimp-like crustaceans that are foundation of Southern Ocean food web. Distinguished from fish oil by EPA/DHA bound to PHOSPHOLIPIDS (rather than triglycerides) — improving bioavailability and tissue uptake. Also contains naturally-occurring ASTAXANTHIN (red carotenoid antioxidant). Higher cost than fish oil; smaller per-capsule EPA/DHA content; better tolerability and absorption claims. Sustainability and ecosystem concerns about Antarctic krill harvesting.

Studied Dose 1-3 g/day krill oil (providing approximately 200-600 mg EPA+DHA — typically lower than fish oil per capsule, but better absorbed)
Active Compound Phospholipid-bound EPA and DHA + astaxanthin

Benefits

Better Bioavailability vs Fish Oil (Phospholipid Form)

EPA/DHA bound to phospholipids (vs triglycerides in fish oil) — better absorbed and incorporated into tissues. Multiple trials (others) show higher omega-3 index increases per gram of EPA/DHA vs fish oil. Translates to lower per-capsule dose for similar effect.

Supported by Trial 2

Improved GI Tolerability

Phospholipid form better-tolerated than triglyceride or ethyl ester forms. Less fishy reflux, less GI distress. Useful for those who can't tolerate fish oil.

Supported by Trial 2

Triglyceride Reduction

Bunea 2004 and others show krill oil reduces triglycerides similar to fish oil at lower per-capsule doses. Effect proportional to absorbed EPA/DHA.

Supported by Trial 1, Trial 2

Astaxanthin Co-Delivery

Krill oil contains naturally-occurring astaxanthin (red carotenoid) — provides antioxidant activity, supports oil stability, may contribute to skin/eye benefits. Astaxanthin content varies by product (typically 0.5-1.5 mg per gram krill oil).

Supported by Trial 2

Joint Health (Modest)

trial showed krill oil reduced joint pain in arthritis patients. Effect via omega-3 + astaxanthin combined activity.

Supported by Trial 1, Trial 2

PMS / Dysmenorrhea (Modest)

trial showed krill oil reduced PMS symptoms vs fish oil. Mechanism via omega-3 effects on prostaglandin synthesis.

Supported by Trial 2, Trial 1

Mechanism of action

1

Phospholipid vs Triglyceride EPA/DHA

In krill oil, EPA and DHA are esterified to phospholipid backbone (mostly phosphatidylcholine) — vs triglyceride backbone in fish oil. Phospholipid-bound omega-3s are absorbed via different pathway — better pancreatic lipase digestion, formation of mixed micelles, possibly direct lymphatic uptake. Result: higher omega-3 index per gram of EPA/DHA consumed.

2

Astaxanthin Antioxidant Activity

Astaxanthin (the red carotenoid that gives krill/salmon their color) — 10× more antioxidant activity than other carotenoids; both lipid- and water-phase active. Protects krill oil from oxidation and provides additional health effects.

3

Choline Co-Delivery

Phosphatidylcholine in krill oil provides ~14% choline by weight — modest choline supplementation alongside omega-3s.

4

Same Underlying Omega-3 Mechanisms

Once absorbed, EPA and DHA from krill oil have same fundamental mechanisms as from fish oil — eicosanoid modulation, membrane composition, etc.

Clinical trials

1
Krill Oil for Hyperlipidemia — Bunea 2004
PubMed

RCT of krill oil (1-3 g/day) vs fish oil vs placebo in 120 hyperlipidemic patients for 90 days.

120 hyperlipidemic patients.

Krill oil reduced total cholesterol, LDL, triglycerides, and increased HDL — equal or better than fish oil at lower doses. Established krill oil as effective lipid intervention. Industry-sponsored study (limitation).

2
Krill Oil Bioavailability — Schuchardt 2011
PubMed

Crossover trial comparing omega-3 index increases from krill oil, fish oil triglyceride, fish oil ethyl ester at matched EPA+DHA doses.

Healthy adults.

Krill oil produced highest omega-3 index increase per gram EPA+DHA vs fish oil triglyceride or ethyl ester forms. Confirmed superior bioavailability of phospholipid form.

Side effects and drug interactions

Common Potential side effects

Generally better-tolerated than fish oil.
Mild GI distress.
Fishy aftertaste reduced vs fish oil.
SHELLFISH ALLERGY — KRILL ARE CRUSTACEANS; AVOID with shellfish allergy (especially shrimp, crab, lobster allergy — cross-reactive).
Bleeding risk theoretical at high doses (similar to fish oil).
Astaxanthin may modify carotenoid absorption.
Pink/red discoloration of capsules — normal (astaxanthin).

Important Drug interactions

Same as fish oil generally.
ANTICOAGULANTS — additive bleeding risk; monitor.
ANTIPLATELETS — additive bleeding risk.
Pre-surgery — discontinue 1-2 weeks before with high-dose use.
SHELLFISH ALLERGY — cross-reactive; AVOID.
Pregnancy — limited specific safety data; fish oil more established for pregnancy use.

More Cardiovascular Ingredients

Cardiovascular
Niacin
Niacin, or vitamin B3, is a vital nutrient that supports energy production by serving as a…
Cardiovascular
Omega-3 Fatty Acids
Omega-3 fatty acids, primarily eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), an…
Cardiovascular
Potassium
Potassium is the most abundant intracellular cation in the human body and an essential min…
Cardiovascular
Pycnogenol® (French Maritime Pine Bark)
Pycnogenol® (Horphag Research) is a standardized extract from the bark of French maritime…

Explore Other Ingredients

Cognitive
Ashwagandha
Ashwagandha is an adaptogenic herb that may reduce stress, enhance mood, and support overa…
Cognitive
L-Theanine
L-Theanine, an amino acid primarily found in green tea (Camellia sinensis), is commonly su…
Antioxidant
NAC (N-Acetylcysteine)
NAC (N-Acetyl Cysteine) is a supplemental form of the amino acid cysteine, best known for…

Related articles from our blog

📝 Article
🔥 The Silent Fire: Understanding Inflammation and the Supplements That Can Help
You can’t see it. You can’t feel it—until it’s done lasting damage. Chronic inflammation is one of the most overlooked d…
June 06, 2025
📝 Article
The Ultimate Guide to Omega-3 Oils: Sources, Spoilage Signs, and Health Benefits 🐟🌿🧠
Omega-3 fatty acids are essential fats—your body needs them but can’t produce them on its own. That’s why getting enough…
July 02, 2025

Frequently asked questions about Krill Oil

What is Krill Oil?

Krill oil is extracted from Antarctic krill (Euphausia superba) — small shrimp-like crustaceans that are foundation of Southern Ocean food web.

What does Krill Oil do?

In krill oil, EPA and DHA are esterified to phospholipid backbone (mostly phosphatidylcholine) — vs triglyceride backbone in fish oil. In clinical research, Krill Oil has been studied for better bioavailability vs fish oil (phospholipid form), improved gi tolerability, triglyceride reduction.

Who should take Krill Oil?

Krill Oil may be most relevant for people interested in cardiovascular, joint health. It has been clinically studied for better bioavailability vs fish oil (phospholipid form), improved gi tolerability, triglyceride reduction. As with any supplement, consult your healthcare provider before starting, especially if you have medical conditions or take prescription medications.

How long does Krill Oil take to work?

Most clinical trial effects appear over weeks of consistent use; individual response varies. Acute or same-day effects (where applicable) typically appear within hours, but most cumulative benefits — particularly those affecting biomarkers, mood, sleep quality, or chronic symptoms — require 4-12 weeks of regular use to fully assess. If you don't notice benefit after 12 weeks at the appropriate dose, it may not be your responder.

When is the best time to take Krill Oil?

For cardiovascular or metabolic goals, Krill Oil is typically taken with meals to support absorption and reduce GI sensitivity. Effects on biomarkers (cholesterol, blood pressure, blood sugar) build over 8-12+ weeks of consistent daily use. Always check product labeling and follow personalized guidance from your healthcare provider.

Is Krill Oil worth taking?

Krill Oil has moderate clinical evidence (Evidence Level 3/5 on NutraSmarts) — meaningful trial support exists, though results are less consistent than top-tier ingredients. Whether it's worth taking depends on your specific goals, what you've already tried, your budget, and your overall supplement strategy. The honest framing: no supplement is essential for most people, and lifestyle factors (sleep, exercise, diet, stress management) typically produce larger effects than any single supplement. Krill Oil is most worth trying if its evidence-supported uses align with your specific goals.

What is the recommended dosage of Krill Oil?

The clinically studied dose for Krill Oil is 1-3 g/day krill oil (providing approximately 200-600 mg EPA+DHA — typically lower than fish oil per capsule, but better absorbed). Always follow product labeling and consult a healthcare provider for personalized dosing recommendations.

What is Krill Oil used for?

Krill Oil is studied for better bioavailability vs fish oil (phospholipid form), improved gi tolerability, triglyceride reduction. EPA/DHA bound to phospholipids (vs triglycerides in fish oil) — better absorbed and incorporated into tissues. Multiple trials (others) show higher omega-3 index increases per gram of EPA/DHA vs fish oil.