Krill Oil: Uses, Dosage, and Safety Information

Overview

Krill oil is a dietary supplement derived from Antarctic krill, small crustaceans that resemble shrimp. Like fish oil, krill oil provides omega-3 fatty acids (EPA and DHA), but with key structural differences that may offer absorption and tolerability advantages.

The omega-3s in krill oil are bound to phospholipids rather than triglycerides, which may improve how the body absorbs and utilizes them. Krill oil also naturally contains astaxanthin, a powerful antioxidant that gives it its distinctive red color.

Common Brand Names

• MegaRed
• Viva Naturals Krill Oil
• Sports Research Antarctic Krill Oil
• NOW Foods Neptune Krill Oil
• Dr. Mercola Krill Oil

Primary Uses

Krill oil is commonly used for:

• Heart health support — similar omega-3 benefits as fish oil
• Joint comfort — anti-inflammatory properties
• Brain health — DHA supports cognitive function
• Cholesterol support — may help maintain healthy lipid levels
• PMS symptom relief — some evidence for menstrual comfort
• Skin health — astaxanthin provides antioxidant support

How It Works

Krill oil provides benefits through several mechanisms:

• Phospholipid-bound omega-3s: This form may be more readily incorporated into cell membranes
• EPA and DHA: Same active omega-3s as fish oil, supporting cardiovascular and brain health
• Astaxanthin: Potent antioxidant that protects the oil from oxidation and provides additional health benefits
• Anti-inflammatory effects: Omega-3s produce specialized pro-resolving mediators

Key Differences from Fish Oil

• Form of omega-3s: Phospholipid-bound (krill) vs. triglyceride-bound (fish oil)
• Absorption: Some studies suggest better absorption with krill oil
• Antioxidant content: Krill oil contains astaxanthin; fish oil does not
• Dose needed: May require smaller doses for similar effects
• Sustainability: Krill fisheries are carefully managed but remain a consideration

Safety Considerations

Krill oil is generally safe but has specific considerations:

• Shellfish allergy: Avoid if allergic to shellfish (krill are crustaceans)
• Blood thinning: Similar anticoagulant effects as fish oil
• Cost: Typically more expensive than fish oil
• Surgery: May need to stop before surgical procedures

Sources

• National Institutes of Health, Office of Dietary Supplements. Omega-3 Fatty Acids: Fact Sheet for Health Professionals. Last updated February 2023. https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/. Accessed March 2026.
• National Institutes of Health, Office of Dietary Supplements. Omega-3 Fatty Acids: Fact Sheet for Consumers. Last updated February 2023. https://ods.od.nih.gov/factsheets/Omega3FattyAcids-Consumer/. Accessed March 2026.
• MedlinePlus. Fish oil. Health topic. https://medlineplus.gov/ency/article/002317.htm. Accessed March 2026.