Cod liver oil, sometimes also referred to as CLO, is a supplement with a long history that is still extremely popular and useful as a source of omega 3 fatty acids for improving your health and increasing your resistance to chronic diseases of all kinds.
It’s often compared with fish oil, as they both provide the benefits of the omega 3 fatty acids EPA and DHA, which are responsible for the health benefits of all types of fish oil. Cod liver oil is higher in vitamin A, a vitamin that is essential for vision, cell growth, and heart function.
We’ve examined the best cod liver oil products on the market and ranked them according to their quality.
Last updated: December 31, 2022
Cod liver oil supplements considered: 22
Hours of research: 37
Experts reviewed: 7
Scientific papers referenced: 15
1. Carlson Cod Liver Oil
Carlson Cod Liver Oil is an extremely well-regarded supplier of this supplement, and its bottle-based cod liver product is everything you’re looking for.
The 500 mL bottle delivers one hundred 5 mL servings, and the only other ingredient is natural lemon flavor–this helps keep the fishy taste of the oil at bay. The total fish oil content per serving is 4.6 grams, and of these, 1.1 grams are omega-3 fatty acids.
With a 500 mg of DHA and 400 mg of EPA, it’s not short on substance. For high-dose fish oil, this is a great way to go.
2. Nordic Naturals Cod Liver Oil
As one of the most widely-known omega 3 fatty acid companies, Nordic Naturals has a reputation for quality, and lives up to it here.
Its liquid cod liver oil supplement uses only natural flavorings and preservatives, like vitamin E and rosemary extract, to increase the shelf life of the oil.
There are 1060 mg of omega three fatty acids per 5 mL serving, which is quite good; the only thing that prevents it from being the top pick is its slightly lower amount of EPA.
3. Athelas Nutraceuticals Cod Liver Oil
Among the softgel-based cod liver oil supplements, the product made by Athelas Nutraceuticals is among the best. With 110 mg of EPA and 100 mg of DHA, the vast majority of the 240 mg of omega 3 fatty acids are comprised of the components you need to get optimal results.
It has no extraneous ingredients, which minimalists will love, though there might be a mild fishy taste to the capsule.
4. Barlean’s Cod Liver Oil
Barlean’s is a bottle-based cod liver oil that is based around freshness–the company even advertises the short shelf life (six months) compared to other companies, who allow their products on the shelf longer.
The omega 3 content is great, with 360 mg of EPA and 540 mg of DHA, though the bottle is only eight ounces, compared to the 16 fluid ounces of some other competitors. Despite this, you can’t go wrong with Barlean’s.
5. Dropi Pure Icelandic Cod Liver Oil
Marketed as a premium cod liver oil supplement, Dropi focuses on purity and high nutritional content. The overall omega 3 content is excellent, at 1150 mg per 5 mL serving, though the EPA and DHA values are middle-of-the-road for a bottle-based cod liver oil supplement.
The other notable facet of this supplement is its unusually high vitamin A content, at 73% of your recommended daily intake. This could be a benefit for some people and a problem for others, since vitamin A is a nutrient that can be harmful when consumed to excess.
So, if you already get a lot of vitamin A in your diet, you’ll want to look elsewhere.
6. Carlson Cod Liver Oil Softgels
While the softgel version of Carlson Cod Liver Oil uses the exact same high-quality oil, the gelatin-based softgel version of the supplement has a disappointingly low dosage.
While it’s certainly possible to just take more softgels, you’ll quickly reach a point where it just makes more sense to get the liquid version, even though measuring precise dosage with liquid supplements can be tricky.
7. Amazing Omega Norwegian Cod Liver Oil
Amazing Omega makes a softgel-based cod liver oil supplement that has a high content of fish oil per capsule, but a disappointingly low EPA and DHA concentration.
In each softgel, there is only 80 mg of EPA and 100 mg of DHA. Amazing Omega does supply fairly high amounts of vitamin A and vitamin D, but those are fringe benefits of taking cod liver oil. The main issue is the content of the omega 3 fatty acids, and specifically the EPA and DHA content.
8. Dr Martin’s Cod Liver Oil
Dr. Martin’s makes a simple, capsule-based cod liver oil supplement. It’s easy to take and helps avoid the fishy taste of liquid form cod liver oil, but unfortunately the EPA and DHA contents are quite low—only 37 mg of each per capsule.
It does have a pretty minimalist ingredient design, but the low dosage is a big downside
9. Blue Ice Fermented Cod Liver Oil
The main selling point of Blue Ice is that there version of cod liver oil is fermented. The company claims that the fermentation process “releases the oil” in the cod liver, but seeing as other companies fare just fine in their cod liver oil supplements without supplementation, it may not be necessary.
10. Solgar Norwegian Cod Liver Oil
Solgar’s cod liver oil supplement is something of a let-down, because the company usually has uniformly high quality across all of its supplements. This one is a bit of an exception.
Each softgel has only 460 mg of cod liver oil, and as you might guess, the omega 3 fatty acid content is a lot lower than that. The EPA and DHA content is only 28 mg each, which makes it very hard to recommend this cod liver oil supplement.
Best cod liver oil overall: Carlson Cod Liver Oil
Thanks to a powerful dose of DHA and EPA, Carlson delivers the omega 3 fatty acids you need for optimal health. Because of this potent dose and the fresh, lemony taste, it takes the top spot.
Best cod liver oil for skin: Dropi Pure Icelandic Cod Liver Oil
Cod liver oil can help restore hyperpigmented skin and clear up scars and blemishes. Thanks to its supreme purity, Dropi is easily the best pick for skincare.
Best cod liver oil for hair: Dropi Pure Icelandic Cod Liver Oil
The same principles that make Dropi ideal for skin care also make it ideal for hair care: with no extraneous ingredients, you’re getting exactly what you need for shinier, healthier hair. Add to that very high vitamin A content and you’ve got a great choice for hair care.
Best cod liver oil for constipation: Barlean’s Cod Liver Oil
If you’re using cod liver oil for constipation, you want something that delivers a wide range of omega 3 fatty acids in liquid form. Barlean’s Cod Liver Oil is ultra-pure and ultra-fresh, making it a perfect niche pick for constipation.
Best cod liver oil for arthritis and joint pain: Nordic Naturals Cod Liver Oil
Nordic Naturals makes excellent fish oils of all kinds. Their cod liver oil is ideal for arthritis and joint pain thanks to having one of the highest concentrations of omega 3 fatty acids on the market.
Best cod liver oil for kids: Carlson Cod Liver Oil
Kids are particularly picky, and won’t put up with fishy-tasting cod liver oil. Carlson Cod Liver Oil uses natural lemon flavoring to achieve a fresh, lemony taste without compromising on purity, making it great for kids.
Who should buy cod liver oil?
Cod liver oil is a plentiful source of omega 3 fatty acids, but you could also get the same benefits from krill oil, fish oil, or a vegan omega 3 supplement. Though fish oil is a better choice for most people, there are a few key groups who might consider cod liver oil instead.
People who want additional micronutrient benefits from vitamin A and vitamin D. Cod liver is packed with vitamin A, so if your diet is deficient in this key ingredient, you might want to opt for cod liver as an omega-3 source.
The vitamin A content of cod liver oil is excellent; a single serving contains nearly 300% of your recommended daily intake. The vitamin A content in cod liver oil might add to the skin health benefits that have been connected to other sources of omega 3 fatty acids.
People who want a naturally-occuring source of vitamin D. Cod liver oil is also one of the few natural source of vitamin D—it is an exceptional source of vitamin D, with over 1300 IUs of vitamin D per tablespoon. That dosage level is something you’d only usually get from a dedicated vitamin D supplement or from direct sun exposure.
People who want omega 3s alongside other nutrients. While cod liver oil is plentiful in omega 3, as you’d expect from a fish-derived supplement, the liver tissue that produces it is also rich in vitamins and minerals.
All the usual benefits of omega 3 fatty acids still apply—you can expect cod liver oil to have the same beneficial effects on risk factors for cardiovascular disease and facilitate the same kinds of improvements in cognitive function and mental health that you’d get with any source of DHA and EPA, but with the added benefits of additional micronutrients.
How we ranked
To formulate our cod liver oil rankings, we combined the best-selling and most popular cod liver oil brands with smaller, specialty companies that focus on high-quality products, and evaluated all on their quality using the following criteria.
Independently-verified purity. We looked for brands that used independent lab testing to ensure purity first of all—as with any fish-derived product, purity is particularly important due to the potential for heavy metals like mercury, along with organic contaminants like PCBs (polychlorinated biphenyls).
Both of these toxins have a tendency to accumulate in the fat tissue of fish, so testing is important to ensure that a cod liver oil supplement is free from contamination.
Omega-3 fatty acid content, especially EPA and DHA. Next up, we examined the omega 3 fatty acid content of the cod liver oils still on our list. Specifically, we looked at the amount of DHA and EPA, in milligrams, per capsule or per fluid ounce of oil.
Nutrition researchers have traced many of the benefits of omega 3 fatty acids to these two specific molecules. EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are two specific types of omega 3 fatty acids which appear to exert most or all of the cardioprotective effects of omega-3 fatty acids, and they are both also directly metabolized by the brain.
For these reasons, we looked for cod liver oils that maximized the EPA and DHA content. This proved to be one of the most important distinguishing factors between cod liver oil brands, since the EPA and DHA content per serving varied wildly from the best to the worst products.
Careful consideration of mechanism of delivery. We also considered the delivery format of the cod liver oil—one of the secondary advantages to cod liver oil is that it is traditionally packaged as a free liquid, not bound up in capsules.
This allows for much more freedom in dosage compared to fish oil or krill oil products that usually only come in a capsule. This can be a boon for people who are looking to customize their cod liver dosing, or who want to mix it into smoothies or shakes.
On the flipside, though,there were several high-quality capsule-based products that still made the cut, since capsules do have certain advantages (not the least of which is masking the fishy taste of cod liver oil).
No unnecessary additives. Finally, we made sure the remaining products had a clean supplement design without unnecessary additives. We made allowances for small amounts of lemon flavoring or other natural flavor sources to mask the taste of cod liver oil (which not everyone enjoys), but mandated that these flavoring agents be naturally derived products.
The final ten cod liver oils, ranked according to quality, combine the health benefits of omega 3 fatty acids with the distinct benefits of high vitamin A and vitamin D concentrations present in cod liver oil.
Q: What is cod liver oil good for?
A: Cod liver oil is a great supplement if you are looking for the benefits of omega 3 fatty acids as well as the micronutrient advantages you can get with vitamins A and D.
Omega 3 fatty acids have been connected with benefits ranging from reduced risk factors for cardiovascular disease to improvements in cognitive function and better mental health.
Vitamin A helps with vision and skin health, and vitamin D plays a critical role in bone health as well as cognitive function. While you could take separate supplements for these other micronutrients, cod liver oil is a traditional supplement that has all three in one.
Q: What are the benefits of cod liver oil vs fish oil?
A: Fish oil boasts a higher concentration of omega 3 fatty acids, including the compounds DHA and EPA, which many researchers believe are responsible for most or all of the health benefits of omega 3 fatty acids.
On the other hand, cod liver oil offers some micronutrients that fish oil does not.
Cod liver oil is exceptionally high in vitamin A, and is by far the best all-natural source of vitamin D. The next closest foods in which vitamin D occurs naturally is mushrooms, which have only a tiny fraction of the vitamin D that you’ll find in cod liver oil.
However, the high vitamin A content in cod liver oil can be a drawback as well—very high doses of cod liver oil can cause vitamin A toxicity, and cod liver oil is not recommended to women who are pregnant.
Q: Should I take cod liver oil?
A: Cod liver oil is best suited for people who want the benefits of a moderate dose of omega 3 fatty acids, plus vitamin A and vitamin D. If you insist that your micronutrients are naturally produced, cod liver oil is an excellent way to get a high dose of vitamin D from a totally natural product.
On the other hand, if you are trying to maximize your DHA and EPA intake, cod liver oil might not be the best choice. The high vitamin A concentration, while beneficial in small to moderate doses, precludes cod liver oil from being taken in high doses.
Q: What animal does cod liver oil come from?
A: Cod liver oil is extracted from the cod, which is a large fish often found in the Atlantic ocean. Cod has become more scarce recently, which has led to higher prices on cod liver oil.
The oil itself, as you can probably guess from the name, is extracted from the liver of the cod, which would otherwise go to waste when a cod is caught for food.
Using the liver as the source of the oil is the reason cod liver oil is so rich in vitamins A and D. These vitamins tend to be concentrated in liver tissue, and since they are fat soluble, they are extracted alongside the oils in the liver.
Despite its decidedly old-school origins, cod liver oil is still an excellent supplement for anyone who wants to improve their cardiovascular health and fight inflammation.
The optimal dosage for most people is 1000 mg per day, but you should be conscious of the vitamin A content of your cod liver oil supplement. The best cod liver oil supplements deliver high doses of omega 3 fatty acids with only a moderate amount of vitamin A.
For BodyNutrition‘s #1 cod liver oil recommendation, click here.