Krill Oil vs. Fish Oil: A Careful Comparison

You may be familiar with fish oil and the health benefits it offers. Fish oil promotes brain health, and it can reduce triglyceride levels. It may help relieve symptoms of rheumatoid arthritis, and it has been shown to help slow the progression of age-related macular degeneration. It’s also been shown effective in treating mood disorders. But what is fish oil, why is it beneficial, and is krill oil better? Let’s break it all down.

What is Fish Oil?

Fish oil is a supplement that’s obtained from fatty fish like mackerel, herring, tuna, and salmon. It’s rife with omega-3 fatty acids, which are central to good health. Omega-3 fatty acids aren’t made by the body, so they need to come from food or supplements.

The two most beneficial omega-3s are eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA. Because of their chemical structure, these are often known as long-chain omega-3s, and both are essential nutrients. Fish oil contains both EPA and DHA.

What is Krill Oil?

Krill oil is also a supplement, but instead of coming from fatty fish, it’s derived from tiny crustaceans known as Antarctic krill. These little creatures are the dietary mainstay of whales, seals, penguins and other marine life.

Like fish oil, krill oil is packed with EPA and DHA, although the structure of the fatty acids in krill oil is different from that of fish oil, which means the body may use it differently.

What’s the Difference Between Krill Oil and Fish Oil?

Visually, fish oil and krill oil are quite different. Fish oil is typically a yellowish color, but the presence of an antioxidant found in krill oil gives this supplement a reddish color. The differing appearance of these oils is only the beginning of the differences between them.


According to a study published in the journal Lipids in Health and Disease, the EPA and DHA in krill oil are absorbed into your blood plasma more effectively than that of fish oil. Another study concurred, finding that after 72 hours of supplementation with fish oil or krill oil, the krill oil group had higher blood concentrations of EPA and DHA.


Antioxidants help protect the body from cell damage caused by molecules called free radicals. Krill oil contains a powerful antioxidant called astaxanthin, which is not found in fish oil. Astaxanthin has antioxidant and anti-inflammatory properties that promote heart health, according to an article published in the American Journal of Cardiology.

Heart Health

Some research shows that fish oil supplements have little effect on heart health when compared to eating actual fish, according to Harvard Medical School. But according to a study published in the Alternative Medicine Review, krill oil, even at lower doses than fish oil, lowered several risk factors associated with heart disease, including blood lipids, triglycerides, glucose, and LDL cholesterol, and it increased HDL levels.

Cost and Availability

Fish oil is less expensive than krill oil, and it’s easier to find on supermarket and drugstore shelves. Krill oil can be up to ten times more expensive than fish oil since it’s harder to collect all those tiny krill and extract the oil.

The Bottom Line

Americans spend $1 billion each year on over-the-counter fish oil, according to Harvard, but it turns out that krill oil may be more effective. It’s absorbed more readily than fish oil, and it may offer heart-healthy benefits that fish oil can’t. If you’re ready to make the switch from fish oil to krill oil, Nerveology’s Antarctic Krill Oil Complex is a high-quality supplement that contains 2,000 mcg of astaxanthin along with phospholipids for increased bioavailability over fish oil.

While krill oil supplementation can bolster your body’s intake of DHA and EPA, it’s still important to get at least some of your omega-3s directly from the source. Along with a daily supplement of krill oil, strive to eat at least two servings of fatty fish each week for the best possible benefits.


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