Fish oil omega 3 content - the sources and ingredients

The fish oil omega 3 content is realized to be very important recenty. Generealy there are two types of fish oil supplements:
- The first is : fish liver oil - this is generally obtained from the liver of the cod, halibut or shark.
- The second is fish body oil - this is normally derived from the flesh of the herring, sardine or anchovy.

Let's see the fish liver oil. Fish liver oil is rich in vitamins A and D. Concentrations in cod liver oil liquids normally range between 750 and 1200 μg (2500–4000 units) vitamin A per 10 ml and 2.5–10 μg(100–400 units) vitamin D per 10 ml. Halibut and shark liver oils are more concentrated sources of these vitamins.
And the fish body oil. Fish body oil is low in vitamins A and D. Vitamin E is also present in both types of fish oil and extra vitamin E is normally added to supplements.
Both fish liver oil and fish body oil are sources of polyunsaturated fatty acids (PUFAs) of the omega-3 series [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)]. These fish oil omega 3 fatty acids are may the most important parts of the oil, the fish oil benefits are connected to them.
EPA and DPA are 20- and 22-carbon molecules, respectively, with five double bonds D5,8,11,14,17, while DHA is a 22- carbon and six double-bond molecule D5,8,11,14,17,20.
All fatty acids (FA) in the fish oil omega 3 family are characterized by having their first double bond at the 3rd position counting from the terminal (o or nth) methyl group in the molecule. As with the omega 6 family, omega 3 fatty acid cannot be synthesized de novo by mammals and must be obtained from the diet.
The structure of the first fish oil omega 3: DHA



The structure of the second fish oil omega 3: EPA






Omega3 and fish oil in BBC
In BBC a short summary about fish oils and omega3 and their effect on brainpower
http://www.bbc.co.uk/science/humanbody/mind/articles/intelligenceandmemory/omega_three.shtml