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Important cod liver oil facts

Cod liver oil is a powerhouse supplement that has been used for hundreds of years for colds and flu, joint and muscle health and many other conditions.

Cod liver oil contains high levels of omega-3 fatty acids (EPA and DHA) , vitamin A and vitamin D and vitamin K. EPA (eicosapentaenoic acid) is the precursor to prostaglandins which act to dispel inflammation and DHA (docosahexaenoic acid) assists in normal brain and central nervous system functioning.

  • Cod liver oil contains more vitamin A and vitamin D per unit weight, than any other food
  • Cod liver oil has high levels of long chain essential fatty acids, which are highly beneficial for heart and circulatory health
  • Cod liver oil is fat soluble

Cod liver oil and health

  • Osteoarthritis - recent research by Cardiff University showed that cod liver oil slowed the destruction of joint cartilage in people with osteoarthritis, as well as reducing pain and inflammation. The study found that 86% of patients reported either significant reduction or total absence the enzyme that causes destruction of cartilage, after taking the cod liver oil supplements, in addition, there was also a great reduction in the enzyme that caused joint pain and inflammation in those patients
  • Blood circulation - the omega-3 fatty acids EPA and DHA discourage blood platelets from sticking together thereby promoting better blood flow, especially in the extremities (legs and arms)
  • Blood pressure - studies have shown that cod liver oil reduces blood pressure by promoting the proper absorption of calcium and magnesium
  • Heart health - studies have shown that cod liver oil reduces the likelihood of blood clotting, makes the heart less prone to arrhythmia's (irregular heart beats), alters the balance of blood fats in a favourable way and reduces the viscosity of blood, thereby facilitating blood flow
  • Healthy skin - the large amount of vitamin A present in cod liver oil is beneficial for skin and mucous membranes
  • Eye health - vitamin A is essential for the the eye to function properly, avoid macular degeneration, cataracts and to promote night vision
  • Babies - when nursing mothers take cold liver oil supplements, breast milk is enhanced two-fold, brain development of the baby is increased and vitamin A levels are increased which stop the baby from getting infections
  • Children's diabetes - a recent study in Norway found that supplementing either the pregnant mother's diet or in the baby's diet in the first year led to a decreased risk for Type 1 diabetes in the child - this is most likely through the anti-inflammatory effects of the long chain omega-3 fatty acids of cod liver oil

People who wish to take an acidophilus supplement should talk to a medical professional BEFORE taking it.

Cod liver oil recommended intake

Dosage of cod liver oil depends on the condition that is being treated. A medical doctor and/or alternative health care provider can advise on individual cases - this information is provided as a guide only.

Check for a supplement that provides sufficient levels of vitamin A and vitamin D - the pages on these vitamins show the recommended daily allowances for each age group and lifestage.

Lifestage Age Amount (per day)
INFANTS 0-12mths Not recommended
CHILDREN 1-8yrs Not recommended
CHILDREN 9-18yrs General health
1 Tsp for every 23kg (50 pounds)
ADULTS 19-50yrs
General health
1 Tsp for every 23kg (50 pounds)
SENIORS 51+yrs General health
1 Tsp for every 23kg (50 pounds)
PREGNANT   Seek advice before taking it
LACTATING   Seek advice before taking it


Types of cod liver oil supplements

Cod liver oil is only found in one food - oil from the liver of cod! Cod liver oil supplementation is available in the following ways:

  • Soft gel capsules - soft gelatin capsules are filled with liquid cod liver oil
  • Liquid - cod liver oil liquid that is usually flavoured as regular cod liver oil is not very pleasant tasting

Cod liver oil supplementation checklist

  • Capsules are a non-fuss easy supplement solution
  • Liquid cod liver oil is better for people who want to take a lower dose or who wish to control their level of dosage
  • Store in a cool, dry place away from light - preferably stored in the refrigerator
  • For better flavour of liquid, find a supplement with a fruity or minty flavour as pure cod liver oil is not very tasty
  • Norwegian cod liver oil is a high quality supplement
  • Should be taken with meals for best absorption

Cod liver oil works best with

Overdosage, toxicity and cautions for cod liver oil

No toxicity has been reported in healthy individuals but people with certain health problems should be careful with taking any supplements.


People with any of the medical conditions listed below should discuss supplementation with a medical profession BEFORE taking cod liver oil:

  • People taking blood thinning medications - such as Coumadin or Warfarin should seek medical advice before taking a cod liver supplement, as there may be bleeding complications - talk to a medical professional
  • People on anti-convulsant medication for epilepsy - are NOT recommended to take essential fatty acid supplements - talk to a medical professional
  • People with diabetes - should be cautious using fish oil supplements as they can raise blood glucose levels and lower insulin production - talk to a medical professional

Large amounts of fish oil supplements (over 5gm/day) can cause blood to become dangerously thin and make bleeding happen more often.



  • Brox JH, Killie JE, Osterud B, Holme S, Nordoy A. Effects of cod liver oil on platelets and coagulation in familial hypercholesterolemia (type IIa). Acta Med.Scand. 1983;213:137-44
  • Moritz V, Singer P, Forster D, Berger I, Massow S. Changes of blood pressure in spontaneously hypertensive rats dependent on the quantity and quality of fat intake. Biomed.Biochim.Acta 1985;44:1491-505
  • Stene LC, Joner G. Norwegian Childhood Diabetes Study Group. Use of cod liver oil during the first year of life is associated with lower risk of childhood-onset type 1 diabetes. Am J Clin Nutr, 2003;78:1128-1134.

Last reviewed 21 April 2019