What Is Cod Liver Oil?

Cod liver oil is a nutritional supplement extracted from the liver of Atlantic cod fish. It is naturally rich in vitamin A, vitamin D, and omega-3 fatty acids, all of which contribute to various aspects of health. Though similar to fish oil, cod liver oil provides higher concentrations of certain vitamins.

Cod liver oil is used to support cardiovascular health, reduce inflammation, and promote bone and muscle recovery—particularly among athletes.

Health Benefits of Cod Liver Oil

May Improve Heart Health

Cod liver oil contains omega-3 fatty acids, which are known to support cardiovascular health by lowering triglyceride levels. Although research on cod liver oil specifically is limited, omega-3s have consistently been shown to reduce the risk of heart disease.

Some studies suggest that cod liver oil may help lower the risk of heart conditions like heart attacks, but more evidence is needed to confirm its effectiveness.

May Reduce Blood Lipid Levels

Cod liver oil may help manage high cholesterol. Fatty acids in the supplement appear to lower LDL (bad) cholesterol and support overall lipid balance. One study found that combining cod liver oil with cholesterol-lowering medication (Rosuvastatin) led to a greater reduction in LDL levels than medication alone.

May Reduce Inflammation

Cod liver oil has natural anti-inflammatory effects thanks to its omega-3 content, along with vitamins A and D. These nutrients help reduce inflammation markers, such as C-reactive protein (CRP), especially after physical activity.

In one study, cod liver oil was more effective than other omega-3 supplements in lowering CRP levels in athletes after intense exercise. However, factors such as dosage, supplement quality, and fitness level may also have played a role.

May Promote Bone Health

Cod liver oil is a natural source of vitamin D, which supports calcium absorption and bone strength. As people age, they are more likely to experience bone loss. Some studies suggest that cod liver oil may enhance bone mineral density, especially in individuals assigned female at birth.

Still, overall findings are mixed, and more long-term research is needed to determine its role in preventing conditions like osteoporosis.

How To Take Cod Liver Oil

Cod liver oil is available in various forms, including capsules, softgels, and liquids. It is sometimes included in skincare products or recipes. When taking cod liver oil orally, dosage depends on the brand and formulation.

Most adult supplements recommend 5–10 milliliters per day for a short duration. Cod liver oil is generally not intended for long-term use without medical supervision. Consult a healthcare provider for personalized guidance.

Safety and Supplement Quality

Since supplements are not regulated by the FDA, it’s important to choose products that are third-party tested. This ensures they are free from harmful contaminants and contain the ingredients listed on the label.

Cod liver oil may contain trace amounts of heavy metals like mercury, which naturally occur in seafood. While small amounts are considered safe, consuming high doses over time could be harmful.

Potential Drug Interactions

Cod liver oil may interact with certain medications, especially blood thinners (anticoagulants). Although rare, high doses of omega-3s may affect blood clotting.

It may also interact with medications containing vitamin A or D, as excessive intake of these vitamins can lead to a condition called hypervitaminosis. Additionally, taking cod liver oil alongside medications for calcium absorption could increase the risk of hypercalcemia, or elevated calcium levels in the blood.

Can You Take Too Much Cod Liver Oil?

Yes, overconsumption of cod liver oil can lead to excessive levels of vitamin A, vitamin D, and omega-3 fatty acids. This could contribute to toxicity or worsen certain medical conditions. Long-term effects of high intake are not well understood, and more research is needed.

Possible Side Effects

While cod liver oil is generally well tolerated, side effects can occur, especially with high doses. Too much vitamin A may cause symptoms such as headaches, blurred vision, and nausea. High omega-3 intake may result in heartburn, loose stools, or gastrointestinal discomfort in some people.

A Quick Review

Cod liver oil is a nutrient-dense supplement packed with omega-3 fatty acids and vitamins A and D. It may offer benefits for heart health, inflammation, blood lipids, and bone strength. Athletes often use it to support muscle recovery.

However, like any supplement, it’s important to take cod liver oil in moderation and consult your healthcare provider before adding it to your routine. Proper dosing and high-quality products can help you gain the benefits while minimizing potential risks.