Cod Liver Oil vs. Fish Oil

Cod Liver OilSupplements play an increasing role in health and nutrition these days. A major reason for this is the quality of the nutrients in the soil has declined over the years due to over farming. What is the difference between cod liver oil and fish oil? Cod liver oil is made from the fish liver of white fish such as cod and halibut. Fish oil is derived from the fatty flesh of the whole fish such as cold water fish like tuna, salmon and mackerel.

How about Omega-3? Both cod liver oil and fish oil contain the same Omega-3’s in similar proportions. Omega-3 promotes heart health, lowered inflammation, decreased formation of atherosclerotic plaques and optimal brain function. Omega-3 can also help relieve symptoms of depression. The major negative of taking cod liver oil is it’s been shown to contain a mixture of potentially harmful contaminants ranging from mercury to chemicals such as dioxanes and PCB’s. There’s also the chance of the rancidity of the cod liver oil. So make sure you keep it in a dark bottle in a cool, dark place.

Cod liver oil also contains the fat-soluble vitamins A and D.  These vitamins are stored in the fish liver so are present in cod liver oil capsules. They are not contained in fish oil capsules. Fat-soluble vitamins can cause toxicity if taken in large quantities. The upper limit intake for adults is 2,000 IU for vitamin D and 3,000 IU for vitamin A. If your vitamin D intake is above this amount it can lead to vomiting, weakness, constipation and nausea. Over the limit for vitamin A could cause liver problems, central nervous system disorders and osteoporosis.

The Verdict?

I used to take cod liver oil capsules as I just assumed if you don’t eat two portions of fish a week then you could get Omega-3 from the capsules. I then became aware of fish oil capsules. I wanted to know the difference and which one should I take. As I mentioned above they both contained Omega-3 so that was good but the game changer was the mixture of potentially harmful contaminants in cod liver oil that come from the fish liver. I knew fish oil did not have vitamin A and D but these could be found in foods or multi vitamins if you were lacking in these vitamins. Cod liver oil is ideal if you don’t get much sunshine and you are lacking in vitamin D but apart from that I would definitely recommend taking fish oil over cod liver oil.


  1. Elena says:

    You can take them any time of day or night, but you’ll always want to take them with food tanikg them without food can make them repeat pretty badly and upset some people’s stomachs. Although if they are chewable pills, they might have added emulsifiers and/or flavors that make them so they don’t need to be taken with food the bottle should say “take with food” or not.They don’t really give you energy or make you sleepy on their own so you don’t have to worry about tanikg them at a specific time. Good luck and I hope I helped![edit]: Dr. T is right, but the level of Vitamin D in Cod Liver Oil isn’t as much of a concern as the Vitamin A levels for most people (unless you get a lot of sun exposure, but that’s more a concern of the sun exposure than CLO exposure). A typical teaspoon of pure and unadulterated CLO has about 1800 IU of Vitamin A and 180 IU of Vitamin D, but many of them have added A and D as well.Most recommendations for pure Vitamin A are between 5-10,000 IU (3-6 tsp of pure CLO) daily, but most err on the side of caution and go more for the 5,000 IU recommendation. Beta Carotene is the exception because the body won’t convert it into Vitamin A until it’s needed so it’s considered safer.Most recommendations for Vitamin D are much more varied on the low end, 1-2,000 IU (5-11 tsp of pure CLO) daily is recommended, but I’ve seen recommendations up to 50,000 IU (short term, of course) for those who are deficient.Because they are fat soluble, both A and D can build up in your system, but you’d be more likely to OD on Vitamin A from CLO way before you OD on Vitamin D (again, unless you have a LOT of sun exposure). I hope that helps to clear it up!

  2. Nick Jarvis says:

    Great comments Elena. I have started to supplement with vitamin D due to the lack of sunshine here in the UK.

Leave a Reply