Can you please tell me about the advantages of fish oil over cod liver oil and what about flax seed oil?

Different: Fish and cod liver oils contain epa and dha, omega 3 fatty acids that are associated with a lower incidence of heart disease. Proposed mechanisms include rasing HDL (good) cholesterol, mild blood thinning, and as anti-oxidants (complicated protective mechanism). Flax seed oil is a monounsaturated substitute for cooking oils such as animal or vegatable oil and is thought to be less harmful.

No advant.,veg. alt.: I do not know of any advantages of fish oil over cod liver oil. Cod liver oil has advantages over fish oil as it is also a good source of vit a & d, not found in fish oils. Any fish or cod liver oil should be purified to remove mercury, pcb's & other toxins. Flax oils is a vegan alternative to fish oil. It has the omega 3 ala which our bodies convert to epa, but not all people make the conversion.