What is the difference between krill oil and fish oil

The benefits of fish oil and it's healthy omega-3 fatty acids are widely studied and it a popular supplement choice for the health conscious among us. Recently however, both researchers and consumers are turning their heads towards krill oil. So what's the difference?

Just like fish oil, krill oil is full of omega-3 fatty acids - most importantly Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA). Omega 3's have been linked to cardiovascular health, healthy cognitive function, joint health and a lot more however krill oil may offer some additional advantages over other marine oils.

There are a number of differences between fish oil and krill oil including the source of the oil used in supplements. the nutrients and the nutritional values within the supplements and how the body absorbs those nutrients.

The two oils come from very different places

Fish oil can come from a variety of fish including anchovies, halibut, herring, mackerel, salmon, sardines, cod and tuna. The fish used to make the fish oil can either be farmed or wild caught.

Krill, on the other hand, are very tiny little crustaceans similar to shrimp that feed on plankton in the waters of Antarctica.

Krill oil is more bioavailable

Research suggests that although both supplements contain EPA and DHA omega-3 fatty acids, the fatty acids from krill may be absorbed better by our bodies. The omega-3 fatty acids in krill are bound to phospholipids which allows them to be released into the bloodstream and cells at a more efficient rate. This mean, you might be able to take less and still enjoy the same health benefits of fish oil.

Another plus point is krill oil doesn’t cause fishy burps like fish oil. This is because the omega-3s in fish oil are bound to triglycerides (fat molecules) which tend to float on the top of stomach fluids whereas phospholipids disperse in water and blend into stomach fluids which results in no fishy aftertaste. 

Krill oil contains additional nutrients

Krill oil also contains choline, and astaxanthin, the carotenoid antioxidant. Choline is an essential precursor to acetylcholine, a stimulatory neurotransmitter, which is involved in healthy brain function and essential for normal function of all cells.

Astaxanthin is a high-powered antioxidant known for supporting healthy skin, eyes, weight, and brain health. You can read about the health benefits of astaxanthin in a previous article.

Which is better?

Due to the fact that the omega-3 fatty acids in krill oil are more accessible for your body to absorb, and that you get a few more nutrients in krill oil it is quickly becoming the most popular source of essential fatty acids. However there are some situations in which fish oil may be a better choice - most importantly, people who are allergic to shellfish shouldn’t take krill oil supplements.

Fish oil may also provide other advantages, including higher total concentrations of DHA and EPA per supplement. Fish oil is usually less expensive than krill oil but it's important to remember that omega-3 fatty acids from krill have better bioavailability therefore your body is able to absorb them more readily than fish oil. So, in other words the lower amount of DHA and EPA in krill oil may be better absorbed than the higher amounts listed in fish oil.

Sustainably and responsibly sourced

Just Vitamins source our Krill Oil from the clean and unpolluted waters of the Antarctic from Aker Biomarine. Sustainability and eco-harvesting is a hugely important factor for this manufacturer. The future of krill as a primary food source is of key importance for the Norwegian economy. The management and sustainable management of krill resources in Norway is supported by WWF-Norway and the krill fishery is certified by the Marine Stewardship Council (MSC). A large investment is made into ensuring that no harm is done to the ecosystem so that we can continue to benefit from this resource as an rich Omega-3 supplement.

A healthy balanced diet is the best way to consume all the nutrients we need. Sometimes however this isn't possible and then supplements can help. This article isn't intended to replace medical advice. Please consult your healthcare professional before trying any supplements or herbal medicines.

Fact Checked

This NativePath content is medically reviewed or fact-checked to ensure factually accurate information.

With strict editorial sourcing guidelines, we only link to academic research institutions, reputable media sites, and, when research is available, medically peer-reviewed studies. Note that the numbers in parentheses (1, 2, etc.) are clickable links to these studies.

The information in our articles is NOT intended to replace that of a qualified healthcare professional and is not intended as medical advice.

Many of us have heard of the benefits of fish oil, but emerging evidence is showing quite the opposite—its lack of benefits. That, plus its large capsule size and the fishy burps that come with it, makes it a less-than-ideal choice for getting your daily intake of omega-3 fatty acids.

Luckily, there’s another marine-sourced omega-3 we can swap for fish oil: Krill Oil.

In this article, you’ll get answers on what krill oil is, the difference between krill and fish oil, and 6 reasons why krill is the better choice for optimal brain health.

What Is Krill Oil?

Krill oil is a type of omega-3 fatty acid that comes from small shrimp-like crustaceans called krill. These creatures move in swarms (more than 10,000 krill per cubic meter of water, in fact) throughout the Antarctic Ocean feeding on microscopic algae, while also serving as a food source for various ocean dwellers including whales, penguins, and seals.

While they may be quite small (about 2 inches in length), krill make up a crucial component of the ocean's ecosystem. Krill literally means “whale food” in Norwegian, and therefore, is the main diet for most marine predators. So much so that it’s referred to as the “keystone species” of the Southern Ocean.

Fun Fact: Blue whales consume nearly 4 tons (that’s 8,000 pounds!) of krill every day.

The Benefits of Krill Oil

One of krill’s underrated superpowers is its extremely high levels of omega-3 fatty acids—particularly DHA and EPA—two long-chain fatty acids that are essential for basic brain functions (1).

In addition to this, krill oil supplementation has shown to improve the following (1, 2, 3, 4):

• Spacial memory and learning
• Memory loss
• Systemic and central inflammation
• Depression symptoms
• Post-exercise immune function
• Hyperlipidemia
• Rheumatoid arthritis

Krill Oil vs. Fish Oil: The 3 Main Differences

Krill oil and fish oil are vastly different. Some of their main differences include:

1. What They’re Sourced From

Krill oil is derived from krill while fish oil is derived from a variety of fatty fish like anchovies, mackerel, and salmon.

2. Antioxidant Profile

Krill contains the essential antioxidant, astaxanthin, whereas fish oil does not.

Astaxanthin is what gives krill their reddish color, and may provide heart health benefits due to its anti-inflammatory and antioxidant properties (5).

3. Effectiveness Per Dose

When it comes to effectiveness per dose, krill oil takes the lead.

One 2004 study found that at equal and lower doses, krill oil was significantly more effective than fish oil in the reduction of glucose, triglycerides, and LDL levels (6).

6 Reasons Why Krill Oil Is Superior to Fish Oil

Yes, krill oil is superior to fish oil when it comes to omega-3 supplementation. But, what makes it the healthier option?

Here are the top 6 reasons...

1. Krill Oil Has Better Absorption

Bioavailability is a term used to describe how much of a substance (EPA and DHA in this case) enters the circulatory system and is used by the body.

With every supplement or medication, some of what you consume is simply excreted and not used by your body. Therefore, bioavailability is an important consideration for nutritional supplements since it indicates how much of an actual effect a substance will have on the body.

Studies have found krill oil has a much higher bioavailability than fish oil, meaning that your body readily absorbs krill oil more effectively than it absorbs fish oil (7).

2. Krill Oil Is More Potent

Potency refers to how much of a substance is needed to produce the desired effect. In the case of omega-3s, the desired effect is the health benefits they offer: A reduced risk of cardiovascular disease, a significant reduction in inflammation, an improvement in depressive symptoms, and more (8, 9, 10, 11).

A 2011 study, found that krill oil is much more potent than fish oil. So much so that some participants received 63% less krill oil than fish oil. And those that took krill oil still had higher levels of EPA and DHA.

While krill oil and fish oil share similar fatty acid profiles, the EPA content in krill is double that of fish oil (7). This proves that you need far less krill oil than fish oil to get the same results (12).

3. Krill Oil Resists Oxidation

Even though polyunsaturated fatty acids (PUFAs) are great for you, the very fact that they are unsaturated also makes them unstable.

There are many techniques that can prevent omega-3s from oxidizing, so it’s crucial that any omega-3 supplement you take comes from a reputable supplier.

Oxidation is not ideal, namely for the following two reasons:

1. Oxidation makes your supplement go rancid.
2. Oxidation creates free radicals (unless there are antioxidants present).

Free radicals are little groups of unpaired atoms that float around your body, pulling electrons off of stable molecules, causing illnesses like atherosclerosis, inflammatory joint disease, diabetes, and more (13).

Research has found krill oil to be significantly more stable than fish oil for two reasons (14):

1. Krill oil naturally contains the antioxidant, astaxanthin.
2. Krill oil’s EPA and DHA are bound to phospholipids (which are readily absorbed by your body), whereas fish oil requires more processing and promotes oxidation.

4. Krill Oil Contains Phospholipids

The EPA and DHA in fish oil is bound to triglycerides, while the EPA and DHA in krill oil is bound to phospholipids (7). This difference plays a significant role in how much your body absorbs.

You know how oil separates from water or vinegar?

That’s how omega-3s are in your body without the support of another substance to help bind them together. For krill oil, those substances are phospholipids. Unfortunately, fish oil doesn’t have this added benefit, making it less absorbable and therefore less effective.

5. Krill Oil Is Free of Contaminants

You’ve probably heard that it’s not the healthiest choice to eat a lot of sushi…

This is due to the high levels of mercury. Because the fish in sushi is high on the food chain (meaning they eat a lot of little fish), they accumulate toxins and heavy metals. For this reason, it’s recommended to not consume certain fish more than a couple of times a month. It’s also why krill oil is a better source for omega-3s (15).

Krill oil doesn’t have the issue of bioaccumulation of toxins and metals because krill is at the bottom of the food chain. Krill feed on phytoplankton instead of other contaminated fish—making them a much safer source of omega-3s.

6. No Fishy Aftertaste

You know how when you take a fish oil capsule, you always get those fishy burps?

You’d think you’d get those same distasteful burps with krill oil capsules, but you don’t!

This is because they don’t dissolve in your stomach. Rather, they stay intact well into your intestines. Which means: No fishy burps or aftertaste!

Krill Oil Dosage: How Much Krill Oil Should I Take Each Day?

When it comes to supplementing with krill oil, the recommended dosage is based on the amount of DHA and EPA found in the supplement.

Krill is a natural blood thinner. So, if you’re currently taking blood thinners, it’s important to be extra mindful of how much krill oil you’re consuming, as it may be a contra-indication. To to be safe, start with a lower dose of krill oil, like 500 milligrams (mg) (16).

This is a “maintenance dose” rather than what you might get prescribed in a clinically setting. For those without cardiovascular risk, it’s safe (and perfectly healthy) to consume a combined EPA and DHA dosage between 250 and 500 mg, which may, depending on the krill oil product, equate to 1,200 to 5,000 mg of krill oil.

Serving sizes among krill supplements varies greatly. So it’s important to talk to a healthcare professional before adding any new supplements to your wellness regimen.

Can I Take Krill Oil and Fish Oil Together?

Yes, you can take krill oil and fish oil together. However, if you were going to choose one supplement, krill oil may be the optimal choice due to its higher concentration of EPA (the omega 3 that gives krill its bright red pigment) and astaxanthin (a powerful antioxidant that reduces inflammation).

If you are going to take both of them together, be sure to only take the minimum recommended serving size so that you aren’t overloading on omega 3s.

Are There Any Side Effects of Krill Oil?

Because omega-3s have anti-clotting effects at high doses, talk to your doctor if you are:

• Taking blood thinners
• Preparing for surgery
• Pregnant or breastfeeding

In addition, if you have any allergies to fish or shellfish, err on the side of caution and get your omega-3s from foods like walnuts, MCT oil, and pasture-raised eggs.

The Bottom Line

Krill oil is undoubtedly making waves in the Antarctic Ocean—both literally and figuratively.

Thanks to these tiny crustaceans, we can experience relief from inflammation, cardiovascular disease, depression, and more.

While you can get some omega-3s by eating fish and plants, the modern diet fails to contain enough omega-3s to make a significant difference in your health. Thus, it’d be wise to consider adding an omega-3 supplement to your diet, especially one high in the brain-boosting DHA (like krill).

Dr. Chad Walding

Dr. Chad Walding

Dr. Chad Walding

As a doctor of Physical Therapy, Senior Wellness Expert, and co-founder of NativePath, Dr. Walding has helped millions of people improve their quality of life from the inside out—by speaking, writing, and educating others on how to live life a little more #OnThePath.

As a doctor of Physical Therapy, Senior Wellness Expert, and co-founder of NativePath, Dr. Walding has helped millions of people improve their quality of life from the inside out—by speaking, writing, and educating others on how to live life a little more #OnThePath.

Medical Disclaimer
This content is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of such advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Chad Walding nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement, or lifestyle program.

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