What Is Krill Oil And What Are It’s Benefits?

Krill oil is a dietary supplement derived from small, shrimp-like marine crustaceans called krill, primarily of the species Euphausia superba, which inhabit the cold waters of the Antarctic Ocean. Known for being rich in omega-3 fatty acids, phospholipids, and antioxidants, krill oil has become a heart- and brain-healthy alternative to traditional fish oil supplements.

Krill oil’s unique biochemical profile, along with potentially better bioavailability, makes it an increasingly researched and preferred source of essential fatty acids.

What Is in Krill Oil?

Krill oil is primarily valued for three key components:

1. Omega-3 Fatty Acids (EPA and DHA)

Like fish oil, krill oil contains the essential omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These fatty acids are crucial for cardiovascular, neurological, and cellular health.

2. Phospholipids

Unlike fish oil, in which omega-3s are bound to triglycerides, krill oil contains omega-3s mostly bound to phospholipids, particularly phosphatidylcholine. This structure is similar to cell membranes, which may enhance absorption and delivery of omega-3s to body tissues, including the brain (1).

3. Astaxanthin

Krill oil naturally contains astaxanthin, a powerful antioxidant that gives krill its reddish color. Astaxanthin helps prevent oxidation of the oil and provides anti-inflammatory and neuroprotective benefits (2).

Health Benefits of Krill Oil

1. Heart Health

Omega-3 fatty acids are well-known for their cardioprotective effects, including:

• Lowering triglyceride levels
• Reducing blood pressure
• Preventing plaque buildup in arteries
• Improving cholesterol profiles

A 2014 randomized controlled trial found that krill oil was effective in lowering total cholesterol and LDL (bad) cholesterol, while increasing HDL (good) cholesterol in participants with mild hyperlipidemia (3).

Because the omega-3s in krill oil are bound to phospholipids, they may be more easily absorbed and utilized than the triglyceride-bound omega-3s in fish oil.

2. Anti-Inflammatory Effects

Chronic inflammation is linked to a range of conditions, including arthritis, cardiovascular disease, and neurodegenerative disorders. Krill oil’s EPA and DHA content and astaxanthin provide anti-inflammatory properties.

A study published in the Journal of the American College of Nutrition found that krill oil supplementation significantly reduced symptoms of arthritis, including pain, stiffness, and functional impairment (4).

3. Brain and Cognitive Function

DHA is a major structural component of the brain, and phosphatidylcholine (present in krill oil) is a precursor to acetylcholine, a neurotransmitter involved in memory and learning. These properties make krill oil beneficial for:

• Supporting cognitive function
• Reducing age-related memory decline
• Protecting against neuroinflammation

Animal studies and preliminary human research suggest that krill oil may improve cognitive performance and protect brain cells from oxidative stress (5).

4. Premenstrual Syndrome (PMS) Relief

Some evidence suggests that krill oil may alleviate symptoms of PMS, such as mood swings, cramps, and bloating. A 2003 study compared krill oil with fish oil and found that women taking krill oil reported greater symptom relief with fewer side effects (6).

5. Joint and Muscle Health

Krill oil’s anti-inflammatory action also extends to joints and muscles. It may reduce post-exercise muscle soreness and improve recovery, especially in individuals with inflammation-related joint pain.

Bioavailability Advantage

One of the reasons krill oil is often preferred over fish oil is its higher bioavailability. Because krill oil’s omega-3s are bound to phospholipids, they integrate more efficiently into cell membranes, allowing for better delivery of EPA and DHA throughout the body.

Studies show that even at lower doses, krill oil can achieve similar or superior blood omega-3 levels compared to fish oil (7).

Sustainability and Environmental Impact

Krill are abundant and form the foundation of the Antarctic food chain. However, due to their ecological importance, sustainability is a key concern. Reputable krill oil brands are certified by the Marine Stewardship Council (MSC) for sustainable harvesting practices.

Technological advances, such as eco-friendly harvesting techniques and real-time monitoring of krill populations, help minimize environmental impact.

Safety and Side Effects

Most people generally tolerate krill oil well. Possible side effects include:

• Mild gastrointestinal discomfort
• Fishy aftertaste (less common than with fish oil)
• Allergic reactions (in people allergic to shellfish)

Due to its anticoagulant effect, Krill oil may also interact with blood-thinning medications (like warfarin or aspirin). Always consult a healthcare provider before starting supplementation, especially if you’re taking medications or have underlying health conditions.

How to Take Krill Oil

Typical dosages range from 250 mg to 1,000 mg of krill oil daily, depending on the concentration of EPA and DHA. Some products standardize these amounts, so it’s important to read labels carefully.

Higher doses may be recommended under medical supervision for therapeutic use (e.g., lowering cholesterol or reducing inflammation).

Krill Oil vs. Fish Oil

Conclusion

Krill oil is a potent source of omega-3 fatty acids with additional benefits thanks to its unique phospholipid-bound structure and antioxidant content. Whether you’re aiming to support heart, brain, joint, or general wellness, krill oil offers a highly bioavailable and effective supplement option.

As with any supplement, quality matters. Look for krill oil products that are sustainably sourced and third-party tested, and provide clear information about EPA, DHA, and astaxanthin content.

References

1. Ulven, S. M., & Holven, K. B. (2015). Comparison of bioavailability and plasma lipid-lowering effects of krill oil vs. fish oil in healthy volunteers. Lipids in Health and Disease, 14(1), 1–8.
2. Guerin, M., Huntley, M. E., & Olaizola, M. (2003). Haematococcus astaxanthin: Applications for human health and nutrition. Trends in Biotechnology, 21(5), 210–216.
3. Bunea, R., et al. (2004). Evaluation of the effects of Neptune Krill Oil on the clinical course of hyperlipidemia. Alternative Medicine Review, 9(4), 420–428.
4. Deutsch, L. (2007). Evaluation of the effect of Neptune Krill Oil on chronic inflammation and arthritic symptoms. JACN, 26(1), 39–48.
5. Rondanelli, M., et al. (2018). Long-chain omega-3 polyunsaturated fatty acids supplementation in cognitive impairment: A systematic review and meta-analysis. Journal of the American College of Nutrition, 37(4), 331–339.
6. Sampalis, F., et al. (2003). Evaluation of the effects of Neptune Krill Oil on the management of premenstrual syndrome and dysmenorrhea. Alternative Medicine Review, 8(2), 171–179.
7. Maki, K. C., et al. (2009). Bioavailability and tolerability of krill oil vs. fish oil. Nutrition Research, 29(9), 661–668.