Krill Oil Vs Cod Liver Oil

The Powerful Battle Between Krill Oil Vs Cod Liver Oil

With both krill oil and cod liver oil being popular supplements known for their omega-3 fatty acids, it can be tough to decide which is better for you. This article looks in-depth at the similarities and differences between krill oil vs cod liver oil, including their nutritional profiles, health benefits, quality considerations, and overall value. Read on to learn whether plankton-eating krill or the venerable cod stands atop the omega-3 food chain!

Omega-3 fatty acids are essential fats with wide-ranging benefits for your health. Two of the most potent sources, the marine oils derived from krill and cod livers, have risen to prominence due to being rich in two specific types EPA and DHA. But how exactly do these oils stack up? With krill largely viewed as an ecological and sustainable choice while cod liver oil boasts generations of proven supplementation, the battle lines are drawn. Below we compare krill oil vs cod liver oil head-to-head so you can determine which is right to address your wellness needs and goals.

Difference Between Krill Oil Vs Cod Liver Oil

Here is a comparison table highlighting some of the key differences between krill oil and cod liver oil

Category Krill Oil Cod Liver Oil
Source Antarctic krill (crustacean) Atlantic cod (fish)
Omega-3 Form Phospholipids Triglycerides
EPA Content 14-15% 9-18%
DHA Content 8-9% 8-14%
Astaxanthin Content Yes, a potent antioxidant None
Vitamin A Content Yes Yes, a higher amount
Vitamin D Content No Yes
Bioavailability Superior absorption, less stomach upset Moderate absorption
Sustainability Marine Stewardship Council certified sustainable Some sustainability concerns due to overfishing
Price More expensive Lower cost typically

Krill oil offers higher omega-3 concentrations in a more bioavailable phospholipid form, also containing the antioxidant astaxanthin. Cod liver oil provides more vitamin A and exclusive vitamin D but can cause stomach upset. Krill oil is seen as more sustainable currently with some cod fisheries struggling.

Krill Oil
Krill Oil

Sources Of Krill Oil And Cod Liver Oil

Here is an overview of the sources of krill oil and cod liver oil:

Krill Oil Source

  • Antarctic krill (Euphausia superba)
  • Small, shrimp-like crustaceans
  • Feed on phytoplankton and algae
  • Harvested from the Southern Ocean using fine mesh nets
  • Caught in regulated fisheries in Antarctica/Southern Chile

Cod Liver Oil Source

  • Atlantic cod (Gadus morhua)
  • Bottom-dwelling white fish
  • Caught wild or farmed throughout the North Atlantic
  • Liver oil rendered from fish caught for the food industry
  • Most cod oil derived from Norway, Iceland, Denmark

Krill are tiny plankton-eating organisms vital to Antarctic food chains. Their oil is extracted onboard catcher boats before transport to production facilities. Meanwhile, cod livers were historically processed onshore close to fishing ports, though modern operations can occur near offshore platforms now.

Both krill and cod oils are ultimately marine in origin – just derived from different creatures and sea locations. Krill comes from pristine polar environments while cod inhabit temperate waters stretching across the currents of the northern and mid-Atlantic oceans. But the livers of these cold-water fish produce an oil exceptionally rich in omega-3s and fat-soluble vitamins.

Sustainability Concerns Krill fishing in the Antarctic is monitored for conservation goals. And improving fish stocks show signs cod fisheries are rebounding too after past overfishing. Still, maintenance of ecologically sound quotas and harvesting methods remains a priority for both krill and cod moving forward.

So while tiny translucent krill and large-scaled cod seem very different, both play pivotal parts in oceanic food webs. Careful stewardship of these resources ensures production of their nutritionally prized oils can persist.

Nutritional Breakdown Of Krill Oil Vs Cod Liver

Krill Oil

  • Fat Content: Triglyceride form — mostly phospholipids
  • EPA: 30-65% of total fatty acids
  • DHA: 14-35% of total fatty acids
  • Astaxanthin: 100-500 mcg per gram

Cod Liver Oil

  • Fat Content: Triglycerides and free fatty acids
  • EPA: 8-18% of total fatty acids
  • DHA: 8-25% of total fatty acids
  • Vitamin A: 450-1,400 mcg per teaspoon
  • Vitamin D: 34-170 mcg per teaspoon

Winner: Krill oil has higher, more potent levels of EPA and DHA omega-3s by volume. But cod liver oil contains vitamins A and D, which also provide health advantages.

Cod Liver Oil
Cod Liver Oil

Necessity Of Krill Oil & Cod Liver Oil

Both krill oil and cod liver oil have their merits and can be useful supplements depending on one’s needs. Here is a quick summary:

Krill oil benefits

  • Higher EPA and DHA omega-3 content per dose than most fish oils
  • Omega-3s in phospholipid form may have higher bioavailability
  • Contains antioxidant astaxanthin not found in fish oils
  • Considered a more sustainable source than fish oils
  • Less prone to oxidation/rancidity
  • Contains fewer potential contaminants

Krill oil drawbacks

  • More expensive than fish oil
  • Limited human evidence so far compared to fish oil
  • Some sustainability concerns still present regarding Antarctic krill harvesting

Cod liver oil benefits

  • Rich source of vitamins A and D in addition to omega-3s
  • Much lower cost source of EPA/DHA than krill oil
  • Generations of use providing safety evidence
  • Sustainability improving with cod stocks rebounding

Cod liver oil drawbacks

  • Lower omega-3 levels per dose typically
  • The risk of rancidity/oxidation is higher
  • Potential for higher contaminants if not molecularly distilled
  • Source fisheries have historically faced sustainability issues

krill oil offers some unique nutrition but has a higher price tag. Cod liver oil delivers great omega-3 value per dollar spent. Using either can make sense depending on a person’s health priorities and budget. Combining them can also provide complementary benefits. But cod liver oil more easily satisfies basic omega-3 needs on a budget without quite matching krill oil’s potency.

Safety And Efficacy Of Krill Oil Vs Cod Liver Oil

Here is a comparison of the safety and efficacy of krill oil versus cod liver oil:


Both krill oil and cod liver oil are generally considered safe, with few side effects in most people at standard supplementation doses. However, there are a few considerations:

  • Contaminants: Cod liver oil is more prone to containing environmental pollutants like mercury and PCBs. But molecular distillation can remove these. Krill oil’s contamination risk is minimal.
  • Allergies: Those with seafood allergies should check if they can tolerate krill and/or fish oils. A test dose is advised.
  • Blood thinning: High doses of either oil could thin blood too much when combined with anticoagulant medications. Consult a doctor first.
  • Vitamin A toxicity: Excessive cod liver oil intake can lead to hypervitaminosis A. Stick to recommended daily amounts.

So both are relatively safe. But krill oil’s purer composition may give it a slight safety advantage. Always seek medical supervision if any concerning symptoms occur with either oil.


Both marine oils are scientifically proven to:

  • Improve cardiovascular health
  • Enhance brain function and mood
  • Reduce inflammation
  • Ease joint discomfort and ensure skin vitality

However, krill oil shows superiority in some studies regarding:

  • Cholesterol and triglyceride optimization
  • Cognitive function support
  • Mental well-being and outlook
  • The potency of anti-inflammatory effects

Krill oil also contains astaxanthin antioxidants to supercharge benefits. So it demonstrates greater efficacy by some metrics – though cod liver oil still effectively promotes health. Using krill oil in contexts where amplified effects are most desirable can maximize outcomes.

Krill and cod oils largely prove safe and effective options. But krill oil’s higher purity, fewer interactions, and heightened bioactivity suggest it may be the more optimal choice from both safety and efficacy standpoints for targeted applications regarding mental acuity, skin health, and chronic inflammation. Consult a natural health practitioner for guidance applying either oil.

Side Effects And Contra-Indication Of Krill Oil Vs Cod Liver Oil

Here is a comparison of potential side effects and contraindications between krill oil and cod liver oil:

Side Effects

Krill Oil

  • Stomach upset or indigestion
  • Loose stools
  • Fishy burps or breath
  • Rash (rare)

Cod Liver Oil

  • Fishy taste
  • Heartburn/reflux
  • Nausea or stomach pain
  • Diarrhea
  • Nasal congestion
  • Headaches

Both oils can cause minor GI irritation in some people. Cod liver oil’s higher vitamin A level also rarely causes headaches or sinus issues. Most side effects are mild.


Conditions or situations where caution should be exercised with krill or cod liver oil supplementation include:

  • Bleeding disorders – As blood thinners, the oils could worsen clotting difficulties
  • Surgery – Discontinuing 2+ weeks pre-operation is recommended
  • Anticoagulant medications – Monitor INR closely and consult a doctor
  • Allergies – Avoid allergic reactions to shellfish or fish sources
  • Pregnancy/breastfeeding – Check with an obstetrician, especially about upper vitamin A limits
  • Hyperthyroid issues – High iodine and/or vitamin A could aggravate
  • Celiac disease – Some risk gluten cross-contamination during processing

Additionally, cod liver oil is not suitable for:

  • Excess vitamin A/D – Don’t overdose further on fat-soluble vitamins
  • Pancreatic insufficiency – Malabsorption contraindicates
  • Kidney disease – Excess vitamin A avoided

Check with your physician about oil safety if you have any medical conditions or take medications that could interact. While generally well-tolerated, krill/cod oils do warrant caution in certain individuals.

Sustainability & Ecological Impact Of Krill Oil Vs Cod Liver Oil

Krill are a keystone organism in marine environments — they convert microscopic phytoplankton into protein available for whales, penguins, and other animals. Some fear overharvesting them could destabilize Antarctica’s food chain. But proponents argue strict quotas prevent this, with less than 1% of total stock currently being fished. The krill fishery was certified by the Marine Stewardship Council as sustainable in 2010.

Atlantic cod stocks collapsed in 1992 and have struggled to recover since overfishing. However, the fishery has strengthened quotas and catch methods allowing the species to rebound in recent years. And the liver oil itself is a byproduct of fish caught for food — utilizing liver parts that would otherwise be discarded to make the oil allows more economic use of the same catch.


Seafood watch groups consider both Antarctic krill and Atlantic cod to be reasonable sustainable/responsible seafood choices currently. Krill may have a slight ecological edge but the margin is not currently definitive.

Health Applications Of Krill Oil Vs Cod Liver Oil

Heart and Circulation Support

The omega-3s in krill and cod liver oils reduce high triglycerides, lower blood pressure, curb inflammation and make blood less likely to clot, helping prevent heart attacks and strokes.

Krill appears slightly more effective by some metrics. One study saw krill lowering LDL and raising HDL (good) cholesterol to a higher degree compared to equivalent doses of fish oil. Krill’s EPA/DHA balance and phospholipid form may enable optimal transport and utilization by the body.

Brain, Memory, And Mood Enhancement

The long-chain omega-3 fatty acids found in both krill and cod oils support neuron structure and development. Research indicates they can stave off cognitive decline, improve memory/recall, and brighten the outlook.

Once again, krill oil has exhibited some superior metrics. One study found it boosted cognitive function by over 40% compared to no treatment. Another saw notable improvements in symptoms of depression and premenstrual syndrome from krill supplementation.

Anti-Inflammatory Effects Of Krill Oil Vs Cod Liver Oil

The omega-3s in marine oils help regulate the immune response, dialing back systemic inflammation. This makes them effective remedies for inflammatory conditions like arthritis, inflammatory bowel disease and more.

While both krill and cod liver oils reduce inflammation, krill oil also contains astaxanthin – an extremely potent antioxidant carotenoid pigment. The combination of marine fatty acids plus this strong antioxidant gives krill an anti-inflammatory and oxidative stress-fighting synergistic advantage.

Joint and Skin Health The anti-inflammatory prowess of krill and cod oils brings relief to sore, swollen joints while also keeping skin supple and aiding wound healing.

Some research gives krill the skincare edge as well — astaxanthin shields skin from sun damage leading to a healthier dermal appearance compared to plain fish oils. Krill’s skin revitalizing antioxidant combo may put it over the top for beauty benefits.


Krill oil’s higher omega-3 levels, different structure, and bonus antioxidant astaxanthin content give it an advantage for heart, brain/mood, anti-inflammatory, and skincare benefits. Cod liver oil still promotes health in these realms, just seemingly to a lower magnitude.

Quality Considerations Between Krill Oil Vs Cod Liver Oil

Rancidity and Contaminants

Krill oil’s phospholipids protect the fatty acids from oxidation – meaning a lower likelihood of rancid oil compared to plain triglyceride fish oils. It also accumulates less mercury, lead, cadmium, and other contaminants due to krill being so low on the food chain.

Cod liver oil is still more susceptible to spoilage/rancidity over time. As larger predatory fish, cod bioaccumulate higher levels of metals that can appear in their livers. The purity level comes down to the processing rigor of the brand.


Krill again due to its more stable nature and freedom from contaminant accumulation worries.

Manufacturing Strictness Of Krill Oil Vs Cod Liver Oil

Reputable krill oil brands adhere to good manufacturing practices ensuring quality from sea to capsule. This includes rapid processing on ships, cold storage, and encapsulation with no fillers. Verification programs like NSF Certified for Sport exist for extra purity assurance.

Cod liver oil production varies more widely – from artisanal small batches to mass manufacturing. Confirming responsible sourcing, testing for toxins, and employing cold filtering all impact quality. Brand trust and recognition go far toward identifying purer products.


Krill oil companies seemingly exhibit more uniform quality control. But both good krill and cod liver oil brands follow stringent practices – while low-end products cut corners – making brand research important either way.

Price Comparison

Krill oil tends to be costlier than cod liver oil on average. Estimated monthly costs for recommended daily amounts range from:

Krill Oil: $30-$50 Cod Liver Oil: $15-$40

So while krill oil represents the fancier option, higher upfront pricing doesn’t automatically equate to good value. We factor that in next.

Value Analysis

To compare value, we must analyze the cost per active omega-3s provided in a typical serving/dose – basically nutrition potency per dollar.

Let’s assume approximate amounts of key fatty acids for representative quality products:

  • Krill Oil – EPA/DHA per pill: 150mg/90mg
  • Cod Liver Oil – EPA/DHA per tsp: 410mg/284mg

If following dosing guidelines to get ~250mg combined EPA/DHA daily, you would require:

  • Krill Oil – 2 capsules
  • Cod Liver Oil – 1 tsp

Using $1/1g krill oil capsules and $0.20/tsp cod liver oil as fair prices:

  • Krill Oil – $2 daily ($60 monthly)
  • Cod Liver Oil – $0.20 daily ($6 monthly)

Per mg EPA/DHA delivered the monthly value comparison is:

  • Krill Oil: $0.24 per mg
  • Cod Liver Oil: $0.01 per mg

So cod liver oil provides substantially more omega-3 value – nearly 25X more mg per dollar!


Cod liver oil is clearly the price-performance victor. Krill oil offers some unique nutrition even if the cost difference based on key fatty acid delivery is vast.

The Verdict: Cod Liver Oil Wins For Overall Value

While cod liver oil can’t quite match krill oil’s impressive concentration and synergies of marine omega-3s and astaxanthin, it still promotes cardiovascular and cognitive health. And it delivers this core nutrition at a fraction of the price – making it the value choice for obtaining high levels of EPA and DHA on a budget.

Krill oil still outperforms at some specific health applications due to its biochemical advantage. For issues like skin vitality, mood balance, and inflammation it can prove the superior therapeutic remedy. And some view its ecological benefits as justification for the premium pricing as well.

So the oils aren’t mutually exclusive either. Rotation or combination may help leverage their varied strengths. But for everyday foundational omega-3 intake cod liver oil gives you substantially more fatty acid bang for your buck.

The better bargain build of this traditional fish-sourced supplement keeps the cod king of cost-effective marine oil nutritionals. Just be sure to source your brand discerningly and you’ll secure optimal quality cod oil at the right cost.

FAQ About Krill Oil Vs Cod Liver Oil

Which is more sustainable – krill oil or cod liver oil?

Currently, both Antarctic krill harvests and Atlantic cod fishing are considered reasonably well-managed for sustainability by reputable rating groups. Cod stock recovery efforts have progressed in recent decades since the fisheries nearly collapsed. Strict monitoring systems ensure minimal krill harvest impact on whale and penguin food sources. So the sustainability difference presently seems small, but ongoing ecological impacts should be evaluated with either marine ingredient.

Is one better than the other for skin and hair?

Krill oil’s antioxidant astaxanthin content gives it a noticeable benefit for skin vitality and appearance. Protecting cell membranes from oxidative damage and UV exposure leads to healthier skin when taking krill oil compared to regular fish oils. This effect can translate to improved hair gloss and strength as well.

Which oil has fewer side effects?

Both krill and cod oils are generally safe supplements, but some people experience minor stomach upset or fishy burps from large fish oil doses. Krill oil’s phospholipid form may make it more digestible, with a reduced likelihood of reflux or indigestion issues. Consult your doctor if any concerning side effects occur.

Can you combine the oils for added benefit?

Yes, taking modest amounts of both krill and cod oils allows you to obtain vitamin A/D along with krill oil’s potent omega-3s, phospholipids, and astaxanthin. A combo approach helps hedge nutritional bets. Take cod oil with breakfast and krill oil with dinner for distribution. This diversifies nutrient sources for enhanced overall welfare.

Last Words

When weighing up krill oil versus cod liver oil, there are good reasons both remain popular supplements. Both provide health-promoting omega-3 fats. Krill oil offers greater potency and some unique properties thanks to its phospholipid structure and astaxanthin content. Yet cod liver oil delivers more value overall, with its much lower cost per mg of EPA/DHA making it easier to obtain therapeutic omega-3 levels affordably.

Cod liver oil also contributes vitamins A and D to address potential deficiencies. So while krill oil should perhaps be viewed as the premium specialty oil, tried and true cod liver oil satisfies baseline omega-3 needs for the masses at a fraction of the price. An alternating or stacked approach also makes sense for obtaining their varied benefits. But for simple omega-3 supplementation, the cod still rules the roost as king thanks to the unbeatable value nutrition its venerable oil provides.


My name is Selina, a medical specialist blogger helping people access treatment for 5+ years. Although blogging awhile, only recently deeply engaged. This past year my most productive, providing hospital reviews and info on symptoms, diagnoses and diseases. Also offer guidelines to help readers navigate healthcare. Goal to continue increased content pace to assist many. Aim to facilitate treatment and empower advocacy through writing.

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