What does cod liver help with? A guide to its many proven benefits

December 28, 2025 •

3 min read

Cod liver oil has been a traditional remedy for centuries, with a long history of use for relieving joint pain and treating rickets, a disease of fragile bones. This potent supplement is packed with essential nutrients like omega-3s, vitamin A, and vitamin D, offering a wide array of health benefits.

Quick Summary

Cod liver oil provides vital omega-3 fatty acids, vitamin A, and vitamin D. It assists in reducing inflammation, bolstering immune function, and supporting bone, heart, brain, and eye health.

Key Points

Reduces Inflammation: The potent omega-3s in cod liver oil are effective at reducing chronic inflammation, which helps ease symptoms of joint pain and arthritis.
Strengthens Bones: Rich in Vitamin D, cod liver oil enhances the body's ability to absorb calcium, which is crucial for maintaining bone density and preventing age-related bone loss.
Supports Heart Health: The omega-3 fatty acids EPA and DHA contribute to heart health by lowering high triglycerides, regulating blood pressure, and reducing arterial inflammation.
Boosts Brain Function: DHA in cod liver oil supports cognitive health, improving memory, focus, and potentially protecting against age-related cognitive decline.
Enhances Vision: With its high vitamin A and DHA content, cod liver oil helps protect against vision loss from inflammatory eye diseases like AMD and glaucoma.
Improves Immunity: The combination of vitamins A and D strengthens the immune system, helping the body fight off infections more effectively.
Benefits Skin Health: Vitamins A and D, along with omega-3s, support skin health by reducing dryness, promoting collagen synthesis, and managing inflammatory skin conditions like eczema.

Nutritional Profile of Cod Liver Oil

Cod liver oil is extracted from the liver of Atlantic cod and differs from regular fish oil, which comes from the flesh of various fatty fish. This source provides a unique nutritional profile, particularly a high concentration of fat-soluble vitamins.

Essential Omega-3 Fatty Acids (EPA and DHA)

Like other fish oils, cod liver oil is a good source of omega-3 polyunsaturated fatty acids, including EPA and DHA. These essential fats, which the body cannot produce, must be obtained through diet or supplements. Omega-3s are known for their anti-inflammatory effects.

Vitamins A and D

A key difference for cod liver oil is its rich content of vitamins A and D.

Vitamin A: Important for healthy vision, immune function, cell growth, and skin health.
Vitamin D: Helps the body absorb calcium for bone health, supports the immune system, and can influence mood.

Key Health Benefits of Cod Liver Oil

Cod liver oil's nutrient mix offers several health advantages.

Supports Joint Health and Reduces Inflammation

The omega-3 fatty acids can help manage inflammatory conditions and have been traditionally used for joint pain and rheumatoid arthritis. Daily use may reduce stiffness, pain, and swelling, and could protect joint cartilage.

Promotes Cardiovascular Health

Regular cod liver oil intake can support heart health. Omega-3s may lower blood triglyceride levels, help regulate blood pressure, and increase HDL cholesterol. Supplementation can complement dietary fish intake recommendations for cardiovascular health.

Enhances Brain Function and Mental Health

As DHA is a major structural component of the brain, cod liver oil is important for cognitive function. Intake is linked to improved memory and focus, and the anti-inflammatory effects may help regulate mood.

Supports Eye Health

Vision loss can be linked to chronic inflammation. The combination of omega-3s and vitamin A in cod liver oil supports eye health. Vitamin A helps maintain vision in low light and protects against conditions like AMD, while omega-3s are key to the retina and may help with glaucoma by lowering eye pressure.

Boosts the Immune System

Vitamins A and D are vital for a healthy immune response, regulating the system and supporting immune cell function. Antioxidant properties of these vitamins and omega-3s can help neutralize free radicals that contribute to inflammation and affect immunity.

Improves Bone Health

Cod liver oil's high vitamin D content can help with age-related bone mass decrease. Vitamin D helps the body absorb calcium, which is necessary for strong bones and teeth. This is particularly useful for older adults and those with limited sun exposure.

Cod Liver Oil vs. Regular Fish Oil

Both cod liver oil and regular fish oil provide omega-3s, but their vitamin content differs.


Feature	Cod Liver Oil	Regular Fish Oil
Source	Codfish liver	Flesh of fatty fish
Vitamin A Content	High	Low or none
Vitamin D Content	High	Low or none
Omega-3 Content	High, slightly lower than pure fish oil	High
Key Benefit Focus	Bones, immunity, vision, heart	Heart and brain

How to Incorporate Cod Liver Oil into Your Diet

Cod liver oil is available in liquid and capsule forms. Taking it with a meal, especially one with fats, can improve absorption and reduce a potential fishy aftertaste. Consistency is important for long-term benefits. For further reading on heart health benefits, an authoritative source is the National Institutes of Health (NIH) [https://pmc.ncbi.nlm.nih.gov/articles/PMC8324067/].

Precautions and Potential Side Effects

Cod liver oil is generally safe, but some may experience mild side effects like heartburn, stomach upset, or a fishy aftertaste. Taking it with food can help. High doses can lead to harmful excess vitamin A intake, so follow recommended dosages. Consult a healthcare professional if taking blood thinners or if pregnant due to potential interactions or vitamin A risks.

Conclusion

Cod liver oil is a nutrient-dense supplement offering benefits for joint health, cardiovascular function, cognitive performance, and immunity through its blend of omega-3 fatty acids, vitamin A, and vitamin D. It supports bone strength, vision, and reduces inflammation. When taken consistently and as recommended, it can be a valuable part of a comprehensive wellness routine.

Frequently Asked Questions

While individual results vary, many people report noticing an improvement in joint pain and stiffness within 2 to 6 weeks of consistent daily supplementation with cod liver oil.

Cod liver oil is not inherently 'better,' but it offers additional benefits. Both contain omega-3s, but cod liver oil is also a rich source of vitamins A and D, which support immunity, vision, and bone health in addition to the heart and brain benefits of omega-3s.

There is no single best time, but taking cod liver oil with a meal, especially one containing healthy fats, significantly improves its absorption. This practice can also help reduce the risk of digestive side effects like heartburn.

When taken in recommended doses, cod liver oil is generally safe. Potential side effects include heartburn, stomach upset, and a fishy aftertaste. Taking it with meals can help. Excessive intake can lead to vitamin A toxicity, so it is crucial to follow dosage guidelines.

Pregnant women should consult a healthcare provider before taking cod liver oil. While the omega-3s are beneficial, excessive vitamin A intake can be harmful to a developing baby. Safe dosages are typically based on the recommended daily intake of vitamins A and D.

A common adult dose is 1 to 2 teaspoons (or capsules) daily. Recommended intake levels are based on safe levels of omega-3s, vitamin A, and vitamin D, and higher doses are not recommended due to the risk of vitamin A toxicity.

Yes, the omega-3 fatty acids and vitamin A in cod liver oil can benefit skin health. They help reduce inflammation and improve skin barrier function, which may soothe symptoms of conditions like eczema, psoriasis, and acne.

Studies suggest that cod liver oil can cause a small but important reduction in both systolic and diastolic blood pressure in people with mild high blood pressure. However, those on blood pressure medication should monitor their levels closely.