cod liver oil is a good source of omega 3 fatty acids, evening primrose oil is a good source of omega 6 fatty acids. both omega 3 and omega 6 fatty acids (also called essential fatty acids) are important for everyone's health, but in people with eczema, the fatty acids are not utilized correctly, causing eczema, asthma, bronchitis. getting a good balance of omega 3 and omega 6 is important...my naturopath said they would saturate all of the cells in my body. i just imagine all of my cells being hydrated again! besides cod liver oil and evening primrose oil, sunflower oil (taken orally -- not cooked), nuts, seeds, and fish are good things to eat a lot of. also, sugar can block the body's ability to use fatty acids, so cutting it out is a good thing to try too.
we did cure my daughter's eczema with just the cod liver and evening primrose oils, but my eczema is more deep rooted (7 years), so i am cutting out sugar, white flour, and taking EPO, fish oil, and sunflower oil...lots of supplements, lots of money, and no sugar or white flour is difficult! but i am feeling very healthy, my eczema is beginning to go away (it's been only 3 weeks) and my diet is fantastically healthy!!! all added benefits.
sorry, i know this is a weak answer to your question, but i am just trying to interpret this sheet of information my naturopath gave me, and it is late and my brain is working about 1/4 power right now!