Cod liver oil and omega 3: a comparison
By Caroline Lilley with expert comment from Linda Main
Published Date: 03/04/2013
Unsaturated fatty acids are an important part of our diet as they are key components of every cell membrane in our body. But where should you source yours from?
What is cod liver oil?
Cod liver oil is derived from the oil of the cod fish. It first came to prominence in northern European fishing communities where fishermen used the oil to protect themselves from the intense cold and soothe the pain of aching muscles. The fisherman would throw the livers of dead cod into a barrel; add water and leave to ferment over time. Cod liver oil, which is still used to treat muscle pain and scar tissue, contains the essential omega 3 fatty acids Eicosapentaenoic acid (EPA) and Docosahexaenoic Acid (DHA), along with vitamins A and D.
What is omega 3?
Omega 3 is an unsaturated fatty acid, derived from vitamin F, commonly found in marine and plant oils. Vitamin F was first discovered in the 1920’s after polyunsaturated fats were withdrawn from mice during experimentation. After the mice fell ill, it became clear vitamin F was made up of two distinct fatty acids: omega 3 and omega 6.
Why do we need omega 3?
Omega 3 essential fatty acids could bring our body a range of health benefits, including lowering cholesterol, helping with mental well-being and improving overall skin appearance. However, unlike other essential nutrients, our body can’t produce omega 3 so we must source it from our diet.
Sources of omega 3
The most common food source of omega 3 is oily fish, such as salmon, mackerel, tuna and sardines. “Omega 3 describes three fatty acids found in our diets,” explains Linda Main, a leading dietician with HEART UK. “They are ALA, DHA and EPA. These can be found in a variety of foods such as flax seeds, soybeans and walnuts. DHA and EPA can be sourced from fatty fish, fish oil and cod liver oil.
“Lowering saturated fatty acids (found in butter, lard, fatty meat and full fat dairy foods) and replacing them with unsaturated fatty acids could help lower triglycerides and blood cholesterol,” Linda says. It’s also available in supplement form.
Which source is best?
If you choose to boost your body’s essential supply of omega 3 from supplements, both omega 3 and cod liver oil supplements are available. The source could come down to personal preference.
“Cod liver oil is a good source of omega 3 if someone doesn’t like eating oily fish or doesn’t eat it very often,” Linda says. “The recommended dosage is 450 milligrams of EPA and DHA and no more than 100% of the RDA for vitamin A for most people.” Cod liver oil is also rich in vitamins A and D so may be preferred by people wanting to boost their body’s supply of these vitamins. However, pregnant women should avoid cod liver oil as it contains high strength vitamin A.
Omega 3 supplements tend to have a higher dose of DHA and EPA fatty acids than cod liver oil and can be combined with other nutrients, such as glucosamine, which could help joint health. Omega 3 supplements are also suitable for people who don’t like oily fish.
Whether sourced from oily fish, cod liver oil or supplements, omega 3 could help those suffering from heart disease, high blood pressure, kidney disease and glaucoma, as well as diabetes, osteoporosis and cognitive decline.