12 Evidence-Based Benefits of Cod Liver Oil

What is Cod Liver Oil

Cod liver oil packs a combination of beneficial nutrients and essential vitamins.

It’s a great source of vitamins A and D.

It also contains Omega-3 fatty acids, which are great for treating inflammation.

However, it’s a fact that most people don’t consume foods that contain a high amount of anti-inflammatory nutrients.

And some people aren’t aware of the possible health benefits of cod liver oil.

For example, fatty acids help boost cardiovascular health, neurological health, the immune system, the reproductive process, and hormones.

Both adults and children can greatly benefit from cod liver oil, either in supplement or liquid form.

One teaspoon of cod liver oil (or one supplement a day) can offer numerous health benefits (in both the short and long run).

So how does cod liver oil work? Well, it comes from a cod’s liver.

You can either buy cod liver oil supplements, or you can buy, prepare, and cook fresh cod liver.

The former is the most popular way of consuming cod liver oil.

According to the US Department of Agriculture, cod liver oil contains approximately 41 calories per teaspoon.

It also contains 4.5 grams of fat, which are split into three categories (polyunsaturated, monounsaturated, and saturated).

The best thing about cod liver oil is that it contains high amounts of omega-3 fatty acids.

You get these fatty acids from healthy, fresh fish (such as salmon, sardines, or mackerel).

On top of that, cod liver oil contains plenty of vitamin D.

In fact, cod liver oil is a natural source of vitamin D.

These essential nutrients relieve inflammation, combat blood clots, enhance brain health, and reduce the symptoms of depression.

Moreover, Omega-3 fatty acids and vitamin D are known for lowering pain levels in inflammatory health disorders (such as arthritis).



The origins of cod liver oil can be traced back to the Viking Era when the oil was used as both a food product and medicine.

Back then, the oil was extracted from fresh fish, and it was an integral addition to the Norse diet.

The Vikings stocked almost all their cod liver oil during the winter.

The days were naturally shorter, which meant there was little sunlight.

Furthermore, winter was the most important season for fishing.

The cod livers remained fresh, which made it easy for the Norse people to extract quality cod liver oil.

The Vikings in Northern Norway used a common technique for extracting cod liver oil – they poured water into a large kettle or pan, boiled it, and placed a couple of birch-tree branches on top of a pan or kettle.

Next, they placed the liver atop the birch branches as the steam came out of the pan.

The liver secreted oil, which dropped into the water.

Once there was a large enough quantity, they skimmed the brown-colored oil, placed more livers on the branches, and repeated the process (although there was no taste or odor of the oil after it was processed in this manner).

Moreover, the Vikings also used to eat the liver after dipping it in the oil.

Commercial Success

The Norse people used to refer to cod liver oil as “lysi” (which means “light”).

Back then, cod liver oil was also used for lighting lamps.

People across Europe used it to illuminate street lights and lamps at home.

The word “lysi” is still used by some people in rural Scandinavian regions.

As generations passed, the name for cod liver oil changed to “tran.”

The word actually has Dutch or German origins, which translates into “tear” or “drop.”

Also, cod liver oil is still a major export for Scandinavian countries.

Used for Medicinal Purposes

Apart from being a commercially successful product, cod liver oil is used for several medicinal purposes.

For example, in the early 1700s, Norwegian Vikings and anglers used cod liver for reducing joint and muscle soreness.

They used to rub the oil all over their bodies to relax their muscles.

During the same time period, several infirmaries and apothecaries stocked up on cod liver oil.

Medical experts began advising patients to use it for numerous illnesses.

For example, cod liver oil was prescribed for people suffering from rheumatism.

In fact, one of the earliest accounts of cod liver oil is used to treat rheumatism was found in a letter written by Robert Darby.

The letter (written in 1782) was found at the Manchester Infirmary in the United Kingdom.

The letter was addressed to Dr. Thomas Percival, and it reflected on some of Darbey’s experiences.

In his letter, Darby expressed his wonder about cod liver oil.

A patient who was suffering from an extreme form of rheumatism was successfully treated for her condition, then completely cured.

She was administered cod liver oil (both internally and externally).

This treatment plan went for a few weeks, after which she could use her limbs without experiencing any pain.




Selecting Cod Liver Oil

The type of cod liver oil you should use specifically depends on what you require it for.

There’s no question that it’s good for your health, but each type of oil offers different benefits.

Cod liver oil supplements can provide you with different doses of Omega-3 fatty acids and vitamins A and D.

Opt for Cod Liver Oil with High Omega-3 Content.

A single tablespoon of cod liver contains 2.89 grams of omega-3 acids.

It also includes high doses of both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Both of these fatty acids are highly recommended for enhancing overall health.

Some cod liver oil supplements are also purified to enhance the potency of EPA and DHA (as well as increasing the overall content).

Steer Clear of Cod Liver Oil Supplements with PCBs.

You don’t have to select expensive cod liver oil supplements, but it’s important to buy supplements from reputable brands.

Then you can minimize the risk of different contaminants (for instance, PCBs and mercury) — which can cause health complications (such as cancer) and birth defects.

Always select cod liver oil supplements that bear the US Pharmacopeia label.

Products with these labels have been thoroughly tested for different types of contaminants.

These products contain the ingredients listed on the back of the supplement.

Take Palatability into Account

There is no doubt that some people have a hard time swallowing cod liver oil in liquid form.

And let’s face it – it tastes bitter and unpalatable.

The solution to this problem is cod liver oil supplements with flavored capsules.

You can select from various flavors.

Plus, these capsules are enteric-coated, which significantly helps reduce the risk of stomach problems (such as gastrointestinal issues).

They may sometimes occur as a result of taking fish oil supplements on a daily basis.

However, it’s important to understand that fish oil supplements are more expensive in capsule form than liquid form.

And to get the daily recommended value of omega-3 fatty acids, you may be required to take two to three capsules every day.

Some Other Things to Consider

Cod liver oil can cause side effects, including dry skin, headaches, bad breath, and an upset stomach.

Therefore, it’s necessary to switch brands after you start experiencing these side effects.

Taking cod liver oil supplements from a different brand can help spread your daily intake of the oil, which may help you combat these side effects and reduce their occurrence.

Furthermore, it’s imperative to read the label of the product.

Many people are allergic to fish products, so they may experience certain complications, including liver and kidney issues.

Another reason why you must talk to your doctor before taking cod liver supplements is that they may clash with other medications.

For example, if you’re on blood thinners, medications for kidney disease, vitamins A, and D, or bone health supplements, they may end up exacerbating these health conditions.


Health Benefits of Cod Liver Oil

Here’s a list of some of the most compelling health benefits of cod liver oil.


Provides Bone Health

Vitamin D is an integral nutrient for boosting bone health.

According to research, women residing in extremely cold regions don’t get enough sunlight, which means no vitamin D.

Therefore, they have an increased risk of several bone disorders, including osteoporosis.

Cod liver contains a healthy balance of vitamin D, which can help you consume the daily recommended value.

Plus, vitamin D in cod liver oil is documented to provide numerous benefits, which include significantly reducing the risk of bone disease and associated disorders [1].


Heals Ulcers

Cod liver oil has also shown positive effects when it comes to healing ulcers and minimizing the symptoms and development of ulcers.

This finding was determined in lab settings, which identified that administering cod liver to rats had gastric, antisecretory advantages.

Moreover, the cod liver oil given to rats also seemed to have gastric cytoprotective benefits in those lab rats.

This helps minimize gastric ulcer pain and discomfort [2].




Enhances Fertility

Fats play an instrumental role in ensuring a healthy reproductive system and a successful pregnancy.

Omega fatty acids help the body produce sex hormones, which include both estrogen and progesterone.

The oil is scientifically proven to help increase both testicular and ovarian health, primarily because it contains essential omega-3 fatty acids [3].

Combined with vitamin D, cod liver oil keeps the endocrine functioning smoothly.

Cod liver oil also contains numerous anti-inflammatory components, which help enhance the pituitary glands, adrenal glands, and hypothalamic system.

These glands are responsible for regulating the release of sex hormones, which help with reproduction and pregnancy.


Treats Arthritis

At the start of the 21st century, medical experts scientifically established the benefits of cod liver oil for treating arthritis.

They stated that the oil had antiarthritic properties.

At that time, scores of mothers began feeding their children a teaspoonful of cod liver oil on a daily basis.

The oil is proven to have anti-inflammatory properties, and it can also be used to reduce pain, treat stiff joints, and minimize swelling.

These benefits are especially handy for people suffering from inflammatory diseases, such as rheumatoid arthritis [4].

Cod liver oil supplements can be used as an alternative to conventional medication.

The oil contains non-steroidal components, which help treat primary clinical symptoms.

It’s a safe, healthy way to reduce several symptoms associated with your joints.




Promotes Cardiovascular Health

Scientific research has proven that taking the cod liver oil can lower your chances of developing cardiovascular complications.

The oil can help reduce the level of triglycerides in the blood.

Triglycerides are a type of fat that can have an adverse effect on your heart, which increases the risk of several heart-related diseases [5].

Moreover, cod liver oil is also good for lowering the symptoms of high blood pressure and balancing cholesterol levels.

Laboratory studies (on both people and animals) have conclusively determined that the omega-3 fatty acid content can significantly help eliminate the chances of developing atherosclerosis (a condition that involves your arteries becoming stiff).

Taking medication and a daily dose of cod liver oil for this condition can reverse the effects of this medical condition, and reduce the risk of the disease in people who have increased triglyceride levels.


Eliminates Cancer Symptoms

Getting a daily dose of vitamin D (from both sunlight and cod liver oil supplements) has been associated with eliminating the symptoms of various types of cancers.

A study revealed that vitamin D from both of these sources can help women who’re suffering from breast cancer.

It also stated that cod liver oil can have an antiproliferative and proapoptotic effect on cancerous cells in the breasts, lowering the risk of tumor development [6].


Helps Control Diabetes

An excellent source of omega-3 fatty acids, cod liver oil can significantly help with insulin resistance (which regulates your blood sugar levels).

Cod liver oil has also been documented to help reduce the symptoms of health complications related to diabetes (for example, kidney issues).

Moreover, studies show that the consistent use of cod liver oil by pregnant mothers can ensure a safe, healthy birth (with a lower risk of diabetes) [7].

Researchers performed a lab-controlled test on rats that had symptoms of elevated blood-sugar levels (including increased triacylglycerol levels and high cholesterol).

After they were given cod liver, the symptoms reduced.

Then the rats experienced healthy weight loss, and the oil helped control their insulin levels.


Source of Vitamin A

Vitamin A is an integral nutrient and antioxidant that helps minimize oxidative stress (which is also referred to as the damage caused by free radicals).

Free radicals can cause several inflammatory diseases and complications.

Cod liver oil counters these effects and eliminates the spread of free radicals.

Vitamin A is also good for maintaining eye and brain health.

Also, it helps keep cancer symptoms at bay and plays an instrumental role in developing hormones [8].


Contains Essential Omega-3 Fatty Acids

There’s no question that cod liver oil is the richest source of essential fatty acids (DHA and EPA).

These Omega-3 fatty acids have powerful anti-inflammatory components, which also help minimize your body’s prostaglandin production.

You can take cod liver oil supplements as alternatives to anti-inflammatory medications.

These fatty acids can help reduce numerous inflammatory symptoms, and they’re especially good for treating coronary heart disease [9].


Reduces Muscle Pain

Frequent muscle pain or bone aches usually point towards a vitamin D deficiency.

Since cod liver oil contains plenty of vitamin D, a daily dose of the oil can help you gradually relieve bone and muscle pain [10].

Cod liver oil is especially important for senior citizens, who have a harder time moving around.

Cod liver oil supplements can help increase mobility and flexibility in your joints.


Boosts Cognitive Function

Cod liver oil contains a powerful dose of omega-3 fatty acids, which are also associated with treating and lowering the symptoms of several brain-related disorders (for example, depression, ADHD, and bipolar disease).

Several research reports have identified that omega-3 fatty acids can indeed have a positive effect on maintaining and regulating cognitive function [11].




Helps Regulate Cholesterol

LDL is the bad cholesterol stored in your body’s fat pockets.

This type of cholesterol can cause numerous cardiovascular issues (and overall health issues).

Because cod liver oil is bursting with a healthy amount of fatty acids, it can help regulate your cholesterol levels (which maintain your cardiovascular health) [12].




Cod Liver Oil Myths

Myth #1: Dangerous Levels of Vitamin A

Vitamin A is an important nutrient.

However, the key to benefitting from this vitamin is ensuring that you balance its intake with vitamin D.

But sadly, there are plenty of cod liver oil supplements that aren’t manufactured with the proper amounts of vitamin D.

Most do include a lot of vitamin D, but the content is usually synthetic.

If you take cod liver oil supplements with high amounts of vitamin A but little vitamin D, it can lead to numerous medical complications (such as osteoporosis).

You won’t have to worry about anything if the supplement you take is manufactured per the standard requirements of quality, and it contains equal amounts of both of these vitamins.


Myth #2: Contains Toxic Contaminants

PCBs and mercury are toxic contaminants, which can lead to numerous health conditions.

However, it’s important to understand that a majority of manufacturers of cod liver oil supplements utilize effective processing strategies (for example, molecular distillation).

This process eliminates heavy metals and other harmful contaminants.

Therefore, it’s imperative that you buy quality cod liver oil supplements.


Myth #3: Regular Fish Oil is Better

A majority of fish oil is extracted from farmed, freshwater fish.

However, these farmed fish are injected with antibiotics.

Did you know that farmed salmon in North America are treated with significant amounts of antibiotics per pound (compared to all other major livestock)?

Moreover, salmon (and all other non-carnivorous fish species) are known to eat just about anything they can find.

So in order to extract fish oil, fish farmers feed them GMO diets.


Myth #4: Best Source of Vitamin D

There’s no question that good cod liver oil supplements contain a high amount of vitamin D, which helps enhance your overall health.

However, a majority of manufacturers use a process to purify the extractions, which requires the use of molecular distillation.

This process drastically reduces the total vitamin D in the oil.

While most add vitamin D back into the mix, it’s important to understand that the added content is mostly synthetic (which has less nutritional value).

Therefore, if you’re taking cod liver oil supplements for the purpose of increasing your daily vitamin D count, it’s important to look for brands that naturally preserve it in their products.

The only way manufacturers can do that is by using old-fashioned extraction methods.

The best place to start looking for a reliable brand is online.

Look for manufacturers that specialize in using old techniques for extracting cod liver oil.

Stay away from brands that use molecular distillation.


Best Ways to Consume

Taking cod liver oil can be a tricky, distasteful experience.

However, below are some tips and tricks for taking cod liver oil, which is much more simple and pleasing:

Taking the Oil Right from the Spoon

This method sounds a bit harrowing, considering how bad it tastes.

But you can pour a tablespoon of cod liver oil, hold your breath, swallow the oil, quickly release your breath, and hold it for another second.

A lot of people have reported that they barely even register the taste.


Because the capsules are coated, this method of taking cod liver oil is probably the best because you don’t have to worry about holding your breath or tasting the oil.

However, supplements cost a bit more.

Mixing the Oil with a Smoothie

When you put the recipe for your favorite smoothie in the blender, add a tablespoon of cod liver oil.

Then drink the smoothie.

You can also add a teaspoon of maple syrup or honey, a couple of drops of water, and a tablespoon of cod liver oil.





Before taking cod liver oil supplements, it’s important to first consult with your medical professional.

This fact is especially relevant if you’re on over-the-counter medications, vitamins, or any other type of dietary supplementation.

If you’ve had a stroke and are taking blood thinners, it’s important to talk to your doctor first.

Therefore, a list of dietary components and medications that can thin your blood are below.

If you take them alongside cod liver oil supplements, you may increase your chances of suffering from bruising, blood clotting, and nosebleeds:

  • Ginseng
  • Ginger
  • Garlic
  • Gingko Biloba
  • Motrin
  • Advil
  • Naprosyn



All in all, the above information cites some of the best health benefits you can enjoy via regular cod liver oil supplementation.

Cod liver oil is a natural source of powerful nutrients, and it can replace convention medicine.

However, before you purchase cod liver oil supplements, you should consult your medical practitioner.

FDA Compliance

The information on this website has not been evaluated by the Food & Drug Administration or any other medical body. We do not aim to diagnose, treat, cure or prevent any illness or disease. Information is shared for educational purposes only. You must consult your doctor before acting on any content on this website, especially if you are pregnant, nursing, taking medication, or have a medical condition.


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