Is Cod Liver Oil Healthy?

author avatar Dr. Eric Berg 08/31/2023

Cod liver oil is a popular dietary supplement used worldwide to promote health and well-being. Cod liver oil is a rich source of fat-soluble vitamins and essential fats required for a healthy body.   

Let’s look at the health benefits of cod liver oil and find out why you should take cod liver oil regularly.

fish and cod liver oil capsules

Is cod liver oil good for you?

Cod liver oil is a nutrient-dense dietary supplement made by extracting oils from highly nutritious cod livers. 

Fat-soluble vitamins are typically stored in the liver, which makes cod liver a particularly rich source of vitamin A, vitamin D, and omega-3 fatty acids. 

You can get fat-soluble vitamins from oily fish, liver, beef, butter from grass-fed animals, and egg yolks. However, cod liver oil contains higher, more concentrated levels of vitamins A and D, making it a convenient source of fat-soluble vitamins.

Watch the video below to learn more about cod liver oil’s incredible nutritional benefits.

Cod liver oil vs. fish oil

Regular fish oil comes from the flesh of oily fish, including tuna, salmon, and mackerel. In contrast, cod liver oil is extracted from the highly-nutritious livers of cod fish.   

Cod liver oil is the most nutritious of all fish oil supplements. While it contains slightly lower amounts of omega-3 fatty acids compared to other fish oils, cod liver oil is packed with vitamins A and D.

Research suggests that regular fish oil intake is linked to a wide range of health benefits. It can lower the risk of cardiovascular disease and diabetes, support cognitive function, boost immunity, and even reduce signs of aging.

The profound health benefits of cod liver oil are primarily due to its high concentrations of vitamins A and D and essential fats, including the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).

Woman taking cod liver oil

Seven health benefits of cod liver oil

Cod liver oil is great for your health. Regular cod liver oil supplementation helps maintain healthy levels of fat-soluble vitamins and increases your intake of healthy fatty acids.

Let’s look at the seven health benefits of cod liver oil.

1. Rich in fat-soluble vitamins 

Cod liver oil is one of the best dietary sources of vitamin A and vitamin D. These fat-soluble vitamins play important roles in maintaining a healthy body.

A single teaspoon of cod liver oil provides as much as 150% of your daily vitamin A requirements and more than half of that of vitamin D. 

Vitamin D deficiency is widespread, and cod liver oil supplements are a great way to achieve and maintain healthy vitamin D levels. 

Vitamin D is crucial for balanced immune function, supports a healthy metabolism and bone health, and has been found to lower the risk of certain cancers and autoimmune diseases.  

Vitamin A is an essential nutrient for cellular and reproductive health. It’s needed for the functioning and integrity of your eyes and skin and protects your body from harmful oxidation. 

You can get vitamin A from dairy, liver, and plant foods, including carrots and green leafy vegetables. However, vitamin A in plant foods is poorly absorbed and requires conversion to its active form. In contrast, vitamin A in cod liver oil is easily absorbed and highly bioavailable.

2. Supports heart health

Similar to fatty fish consumption, cod liver oil helps lower your risk of heart disease and stroke. 

Omega-3 fatty acids in cod liver oil have well-documented health benefits. Studies report that regular EPA and DHA intake helps lowering blood pressure, balances blood triglyceride levels, and increases levels of heart-healthy HDL cholesterol.

3. Improves eye health 

Cod liver oil intake can protect you from vision loss and night blindness. It also lowers the risk of glaucoma and age-related macular degeneration, the world's leading causes of blindness.

Vitamin A has potent antioxidant properties that protect the delicate structures in your retina from oxidation. 

Rhodopsin, a protein in your eye that allows vision in low-light environments, contains vitamin A. This explains why vitamin A deficiency lowers your ability to see in the dark. 

Cod liver oil supplements

4. Lowers inflammation    

Cod liver oil contains three essential nutrients that help your body fight chronic inflammation. 

Inflammation is an important body function. However, chronic and unresolved inflammation increases the risk of serious health conditions, including autoimmune diseases, cancers, and diabetes. 

Omega-3 fatty acids have potent anti-inflammatory properties and suppress the production of proteins that exacerbate and prolong inflammation. 

Vitamin D appears to lower inflammation by stimulating anti-inflammatory immune cells and promoting balanced immune functions, reducing the risk of overt immune responses and chronic inflammation.   

The antioxidant properties of vitamin A protect the cells in your body from harmful oxidation that can lead to inflammation and cell damage.

5. Supports bone health 

Cod liver oil has been used to treat rickets and other bone deformities for centuries.

Vitamin D plays a crucial role in bone formation and skeletal health. Without vitamin D, your body can't absorb the calcium needed to produce bone tissue. Vitamin D deficiency can increase your risk of osteoporosis later in life.

Cod liver oil supplementation has been found to improve bone density and can protect from age-related bone loss.

5. Promotes healthy skin 

Taking cod liver oil is a great way to support your skin health.

Skin cell formation, skin renewal, and wound healing depend on vitamin A. Vitamin A deficiency is linked to the development of skin conditions, including psoriasis, eczema, acne, and atopic dermatitis.

Vitamin A also reduces the impact of UV damage on your skin and stimulates the production of collagen, the protein that keeps your skin tight and firm.

6. Boosts your mood 

The combination of vitamin D and omega-3 fatty acids in cod liver oil supports your brain health and may boost your mood.

Vitamin D promotes healthy brain function and increases neuronal sensitivity to serotonin, a mood-boosting neurotransmitter. Vitamin D deficiency increases the risk of depression and anxiety.

Essential fatty acids, including DHA and EPA in cod liver oil, support your nervous system's overall health and maintain neuronal health and integrity.

7. Improves rheumatoid arthritis symptoms 

This study found that daily cod liver oil supplementation reduced symptoms of rheumatoid arthritis, including swelling, arthritis pain, and morning joint stiffness. 

The effects were so profound that participants who took cod liver oil significantly reduced their use of anti-inflammatory medication.

Cod liver oil capsules

How much cod liver oil should you take?

A typical daily dose of liquid cod liver oil is between one and two teaspoons. You can also choose cod liver oil in capsule form. Read the label for recommended dosage. 

Cod liver oil is highly nutritious and supports a healthy body. However, in some instances, cod liver oil may not be the right choice for you.

Marine oil supplements, including cod liver oil, can act as a blood thinner and increase the risk of bleeding. It's best to check with your doctor if you take blood thinners or blood pressure medications. 

Fat-soluble vitamins are stored in the body, and excessive intake can lead to toxicity and harmful side effects. Pregnant women should avoid cod liver oil. High amounts of vitamin A can cause harm to an unborn baby and result in congenital disabilities.

Most cod liver oil comes from Pacific or Atlantic cod. For the best quality product, choose virgin cod liver oil produced without the use of high heat or chemicals.

Cod liver fish oil capsules

Key takeaways

Cod liver oil is on our Healthy Keto® Food List because it’s highly nutritious and has a wide range of health benefits. It provides a unique combination of omega-3 fatty acids, vitamin D, and vitamin A.

Regularly taking cod liver oil supports cardiovascular health, helps lower blood pressure, reduces inflammation, and can protect you from vision loss.

Cod liver oil supplementation is convenient and available in liquid form or as capsules. Taking one to two teaspoons of liquid cod liver oil daily supports optimal nutrient levels and benefits your health.


1. Is taking cod liver oil healthy?

Yes! Cod liver oil is exceptionally healthy. It’s a rich source of heart-healthy omega-3 fatty acids, vitamin D, and vitamin A. 

The combination of these essential nutrients makes cod liver oil the most nutritious of all fish oils.


2. What are the health benefits of cod liver oil?

Taking cod liver oil has many health benefits. EPA and DHA in cod liver oil are potent anti-inflammatory fatty acids that help your body to fight chronic inflammation, lowering the risk of cancer, heart disease, and metabolic syndrome.

Vitamin A, a fat-soluble vitamin, is vital for immune system function and reproductive health and supports healthy skin and vision.

Vitamin D promotes strong immunity and healthy bones, protects your cognitive health, and lowers the risk of autoimmune diseases, including multiple sclerosis, psoriasis, and autoimmune thyroid disease. 

3. Which is better, fish oil, or cod liver oil?

Cod liver oil is a rich source of essential fats and fat-soluble vitamins A and D.

Depending on the type, fish oils can contain slightly higher amounts of omega-3 fatty acids compared to cod liver oil. However, other fish oils don’t provide significant amounts of vitamin A or D.

4. Can I take cod liver oil every day?

Yes, regular cod liver oil supplementation is an excellent choice for your health. A typical dosage of cod liver oil is one to two teaspoons daily.

5. Will cod liver oil break my fast?

No, taking a typical dosage of cod liver oil won’t break your fast.

However, taking cod liver oil on an empty stomach may make you nauseous. Combining cod liver oil with a meal most likely fixes this issue.


6. Will cod liver oil reduce cholesterol?

Cod liver oil is unlikely to lower your cholesterol levels, but it does increase levels of heart-healthy HDL cholesterol linked to a reduced risk of arterial plaque formation, stroke, and heart attacks. 

7. Can I have cod liver oil on keto?

Cod liver oil is an excellent source of nutrients, including omega-3 fatty acids, vitamin D, and vitamin A. Because it contains no carbs, cod liver oil is a keto-approved supplement for your low-carb diet.

8. Does cod liver oil go bad?

Cod liver oil is rich in polyunsaturated fatty acids. Unfortunately, these fatty acids can quickly become rancid. Most cod liver oil manufacturers recommend keeping cod liver oil away from heat and light. To maintain the best quality, store your cod liver oil supplements in the fridge and dispose of expired fish oil products.

9. Does cod liver oil contain omega-3 fatty acids?

Yes, cod liver oil contains both EPA and DHA. Although other fish oils provide slightly more omega-3 fatty acids, cod liver oil contains around 8% EPA and up to 18% DHA.

10. Does cod liver oil have mercury?

Cod is a smaller cold-water fish that consumes small shrimp and other crustaceans. As a result, cod liver oil doesn’t contain high levels of mercury.

11. Will cod liver oil make me smell?

Some people develop an unpleasant body odor or bad breath after taking fish oil supplements. It’s believed that impurities in fish oils can increase the risk of developing pungent sweat and fishy breath. Choose high-quality virgin cod liver oil to avoid fish oil-related body smells.

12. How much cod liver oil should I take?

A typical daily dose of liquid cod liver oil is between one and two teaspoons. You can also choose cod liver oil in capsule form. Check the label for recommended dosage.

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