Cod Liver Oil: Benefits and Side Effects

Cod liver oil is a popular supplement from Atlantic cod fish. It is rich in several essential nutrients, including vitamin A, vitamin D, and omega-3 fatty acids.

Although similar, there are nutritional differences between cod liver oil and fish oil supplements. Consuming cod liver oil can improve blood lipid levels, reduce inflammation, and strengthen your bones. Cod liver oil is also commonly used by athletes to help with muscle recovery.

High amounts of omega-3 fatty acids in cod liver oil have been shown to improve cardiovascular health by reducing triglycerides (a type of fat) in your body. Limited studies show the effects of cod liver oil specifically, but many studies support the effects of omega-3 fatty acids for preventing heart disease.

Another study suggests that using cod liver oil supplements may slightly reduce the risk of cardiovascular conditions like myocardial infarction in participants. Still, more research is needed to confirm how effective cod liver oil is at keeping your heart healthy.

Having too many lipids in your blood can cause hyperlipidemia (also known as high cholesterol). Fatty acids in cod liver oil help balance lipid levels in the body. There is limited research on the effect of cod liver oil alone, but some studies found a decrease in lipid levels when participants also took cholesterol medications.

In one study, participants who consumed cod liver oil and Rosuvastatin (a cholesterol-lowering medication) had significantly lower low-density lipoprotein (LDL) cholesterol levels.

Research suggests that cod liver oil may have stronger effects than some other omega-3 supplements. Vitamins A and D in cod liver oil have antioxidant and anti-inflammatory effects. This is why taking cod liver oil supplements can help your muscles recover from soreness caused by inflammation in your muscles.

A C-reactive protein (CRP) test measures the levels of CRP in your blood. As inflammation increases, so do your CRP levels. One study found that cod liver oil lowered CPR levels significantly more than other omega-3 supplements in athletes after intense physical activity.

However, other factors, such as how long the athlete has been working out and the dosage and quality of the supplements taken, may have also influenced the study. More research is needed to confirm how cod liver supplements compare to other omega-3 sources in reducing inflammation.

As you age, your body is naturally at an increased risk for bone health conditions like osteoporosis (bone loss) and bone fractures.

Researchers found no significant difference in hip bone strength among participants who took cod liver oil supplements daily. The study examined how cod liver oil consumption affects bone health as a person reaches the ages 66-96. Still, people assigned female at birth who took the supplements daily saw more bone mineral strength than participants assigned male at birth.

Cod liver oil supplements are sold in capsule, liquid, and liquid-filled capsule forms. There are also cod liver oil products for the skin, such as ointment and creams with antibacterial properties. Cod liver oil is also a part of some recipes.

Dosage

How much cod liver oil to consume depends on the brand. Most brands recommend 5-10 milliliters (mL) daily for adults for a limited time period. Most cod liver oil supplements are not meant for long-term use. Consult your healthcare provider before adding cod liver oil supplements to your routine.

Try to find a cod liver oil supplement that is third-party tested. Unlike medications, the U.S. Food and Drug Administration (FDA) does not regulate supplements. Using a third-party tested product further ensures that supplements contain only the ingredients listed on the label.

Some supplements can contain harmful contaminants like heavy metals. Heavy metals are natural metallic elements found in the environment. Ingesting too much of heavy metals like mercury and iron can lead to intoxication. Seafood is more likely to have high levels of heavy metals like mercury. However, heavy metals are generally safe when consumed in moderation.

Potential Drug Interactions

There is not much information on the interaction between cod liver oil and other drugs, herbs, or supplements. Consult your healthcare provider if you also take anticoagulants (medication that prevents blood clots). Although rare, supplements high in omega-3 fatty acids can increase your risk of blood clots if taken with certain medications.

High levels of vitamin D in cod liver oil supplements may interact with statins (medications to lower blood lipid levels) and other medications containing high levels of vitamin A. Ingesting too much of a certain vitamin can lead to hypervitaminosis (an overconsumption of vitamins).

Vitamin D helps your body absorb more calcium, which improves bone health. Taking cod liver oil supplements with medications that treat calcium loss can potentially cause hypercalcemia (excessively high levels of calcium).

Can You Take Too Much Cod Liver Oil 

It is possible to take too much cod liver oil. Consuming high doses of cod liver oil supplements for an extended period of time can cause excessive intake of vitamin A, D, and omega-3 fatty acids. This can worsen certain health conditions, but more research is needed to know how much taking cod liver oil for years affects your health.

There is not much data on the side effects of cod liver oil specifically. Still, consuming too much of certain nutrients in cod liver oil supplements can affect your health.

For example, consuming too much vitamin A can cause headaches, nausea, and blurred vision. For some people, consuming too many omega-3 fatty acids can cause nausea, heartburn, and diarrhea.

Cod liver oil is a type of fish oil with a good source of omega-3 fatty acids, vitamins A and vitamin D. Athletes most commonly use it as a supplement to keep their muscles and bones healthy. Taking cod liver oil supplements can improve your heart health and blood lipid levels and reduce muscle inflammation after a workout.

More research is needed to know how effective it is for your body over a long period of time. Consult your healthcare provider before adding cod liver oil supplements to your daily routine. They can guide you on how much to take and how it may benefit your health.