This question was posed to me by @onesixeightfit (Becky White) and I said I would look into it. First, however, let me establish a few basic facts first:
Helps reduce risk of rheumatoid arthritis in women
Deficiency in vitamin D has been linked to cancer
See more information about this here
Cod liver oil is a good source of vitamin A, D and Omega 3 fatty-acids
What can Cod liver oil do for me then?
To read the research that supports each of these claims, click the text to follow the link
reduces anxiety, depression and sleeping problems EicosaPentaenoic Acid (EPA)
Strengthen Bones and Teeth (vitamin D)
Improve Vision – Vitamin A helps to maintain a healthy immune system, helps resist bacterial and viral infections, and beneficial for eyesight and healthy skin. Also DocosaHexaenoic Acid (DHA)
Omega 3 is important for the brain development of the foetus in Pregnancy It also has anti-inflammatory properties which help relieve the symptoms of arthritis, improve brain function, reduce stress, prevent allergies, relieve asthma, and help with learning and behavioral disorders including bipolar syndrome.
Arthritis – Improvements in the symptoms of rheumatoid arthritis have been reported in patients taking fish oil supplements. EicosaPentaenoic Acid (EPA)
Real life cases:
I asked my Dad, who has taken Cod liver oil for years now, what he thought they did for him. He said he took it because he had trouble with his knees. He used to regularly walk the couple of miles from our house to church on Sundays. He says he noticed an increased problem with pain and mobility in his knees if he stopped taking cod liver oil. He also told me about a little old lady called Evelyn, who lived across the road from us when I was a child. She took a spoonful of cod liver oil every day all her life, and was still able to walk miles to everywhere well into her 70’s. I have recently started taking both Glucosamine and code liver oil, again, for my knees, having sustained major injuries in my younger days as a rugby player. I too would say that I get more pain if I forget to take them regularly, however have not taken the glucosamine and the cod liver oil in isolation from each other, so it is hard to isolate what exactly is having a positive effect on me in this case.
The research suggests that cod liver oil does help reduce blood pressure, but the effect is a small one. There is more strength, however, in the research findings that support the fact that cod liver oil improves blood flow. (This research is related to how platelets form). There is strong clinical research to support the fact that it helps with arthritis, and that it helps also with anxiety and sleeping problems. The research is conflicting with relation to bone density and calcium absorption. http://onlinelibrary.wiley.com/doi/10.1359/jbmr.2002.17.4.709/pdf There is very little human based research on the benefits of fish oil on bones and teeth, however if the search is refined to calsium absorbition in connection with vitamin D (which is one of fish oil’s main beneficial ingredients) then there is much stronger research to support this. (Dawson-Hughes, Karis, Krall and dallal,1997) Although the clinical improvement in arthtritis may only be moderate, studies show that the improvement in pain is much more marked. (Tidow-Kebritchi and Mobarhan, 2009) There is VERY STRONG research to support the reduced risk of cancer and its connection with fish oil supplements. Night vision improvements are linked to vitamin A supplements, a vitamin which is contained in fish oil. The research into fish oil is endless, as are its benefits, it seems. Initial research into effects on dermatitis are promising, and I imagine, was I to research all the claims stated for the benefits of fish oil / cod liver oil then I feel confident I would find much more research to support it. Also worth a read: http://www.homeremediesweb.com/cod-liver-oil-health-benefits.php
Quite honestly, I was astounded at the amount of research that has taken place into the benefits of fish oil, and I was even more astounded to discover the long long list of health benefits that have been discovered so far.