Differences, benefits, types and more

Both cod liver oil and fish oil are sources of omega-3. Omega-3s are a group of fatty acids that, in small doses, are important for human health.

Most studies focus on three types of omega-3: alpha-linolenic acid (ALA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The benefits of each acid can vary slightly, so getting all three can improve your health.

A person needs to get these acids from their diet; the body does not do them. ALA converts to EPA and then DHA, but the conversion rate is low. To get optimal Omega-3 benefits, a person must take DHA and EPA.

Cod liver oil is a type of fish oil. The main differences between cod liver oil and other fish oils include:

• Different vitamins: Cod liver oil contains vitamins A and D.
• Omega-3 content: Cod liver oil comes from cod liver oil, which is less fatty than other fish, such as tuna and mackerel. For this reason, cod liver oil provides a lower dose of omega-3.
• Other health benefits: In addition to the supposed benefits of omega-3, cod liver oil has long been a popular folk remedy for managing constipation, and inducing labor.

While cod liver oil is a type of fish oil, people usually use the term “fish oil” to refer to fatty fish oils, such as tuna and mackerel.

Some research shows that omega-3 can improve heart health by lowering blood pressure or reducing the risk of heart attack. Most such research has focused on populations that have a lot of fish oil in their diet, not on people who supplement with fish oil.

However, not all research supports these potential benefits. A study from 2012 among people with diabetes found that omega-3 supplements reduced triglyceride levels, but did not reduce the risk of having a heart attack.

Omega-3 supplements, including fish oil, can also:

Researchers continue to study omega-3s for a wide range of conditions, but the data so far are inconclusive. For example, a 2019 meta-analysis of omega-3s suggests that they may improve the symptoms of depression, but other studies have been inconclusive or undermined this claim.

Like other fish oils, cod liver oil can reduce the risk of medical conditions. A 2014 cohort study which followed a group of people who supplemented with cod liver oil and a group who did not find a lower risk of heart disease in the group who took cod liver oil.

The study also found that users of cod liver oil had more health problems and were more likely to report bone disease and benign growth.

The study’s authors suggest that people with health problems may be more likely to take cod liver oil. In addition, they found that users of cod liver oil had a healthier lifestyle, suggesting that other differences may explain the different health outcomes between groups.

Other research also suggests the health benefits of cod liver oil. A 2011 study points out that because it is a source of both omega-3 and vitamin A, cod liver oil can help protect against glaucoma.

Vitamin D plays an important role in health. About a quarter of Americans may be deficient. Cod liver oil is a source of vitamin D and, as such, can provide the following health benefits:

• reducing the risk of osteoporosis, especially when a person takes it with calcium
• decreasing the risk of developing certain types of tumors
• improving the health of the immune system
• supporting glucose metabolism

Emerging evidence suggests, but does not conclude, that the risk of severe COVID-19 disease is higher in people who do not receive enough vitamin D.

Learn more about the benefits of fish oils here.

Because cod liver oil and fish oil are both fish oils that contain omega-3 fatty acids, the risks are similar. They include:

• Fish allergies: Fish oil supplements can trigger some fish allergies. In some people, the reaction may be severe.
• Stomach problems: Some people who take fish oil supplements experience stomach problems such as bloating, gas, diarrhea or constipation.
• Taste of the bath: Fish oil can leave a fishy taste in the mouth and a person may notice bad breath immediately after taking the supplement.
• Blood pressure: Limited research suggests that omega-3 may lower blood pressure. People taking blood pressure medications should talk to a doctor before trying these supplements.
• Blood coagulation: Omega-3 could also affect blood clotting, so people with clotting disorders, bleeding disorders and those taking coagulation medications should talk to a doctor before supplementing with fish oil.
• Interactions with other drugs: Doctors have not identified all possible drug interactions associated with fish oil, so people taking any medicine that is vital to their health should talk to a doctor before supplementing.

There are three main types of cod liver oil and fish oil supplements:

Food

A person can get cod liver oil by consuming cod liver. A number of foods, including most fish, are good sources of omega-3 fatty acids and can provide superior benefits to supplements. Fatty fish, such as tuna and mackerel, are the largest in omega-3s.

Oils

A number of manufacturers produce pure fish oil or fish oil formulas that contain other supplements. These oils usually contain higher concentrations of fish oil, but may taste bad.

Tablets

Fish oil capsules can be a more enjoyable option for people who do not want to use fatty supplements.

alternative

Vegans and vegetarians may not want to eat fish oil. Flaxseed oil contains omega-3, but not EPA and DHA in fish oil. Algae oil contains DHA, but not EPA.

The latest review by the Institute of Medicine to determine the correct dose of omega-3 was based on inconclusive data. Instead, the organization analyzed average intakes in healthy groups and recommended the following daily intakes:

Eating two to three servings of fish a week can also help a person get the recommended amount of omega-3.

Supplements vary in the amount of omega-3 present as well as the type of omega-3. It is important to check the label. Users should also look for other ingredients, as taking too many supplements may increase the risk of vitamin overdose.

Most research shows that food is a healthier source of fish oil and that the apparent benefits of omega-3 may be less obvious when a person takes supplements. For example, the cardiovascular benefits of omega-3 may be present only in people who eat foods rich in omega-3, not supplements.

Omega-3 in cod liver oil and fish oil can provide important health benefits and there is little evidence that it can harm healthy people.

To get the most benefits, consider increasing your fish intake. People interested in trying supplements should talk to a doctor first.

For those who do not want to eat fish products, there are other excellent sources of omega-3, such as seaweed oil.