The 2 types of EFA we need to have in our diet are Omega 3 and Omega 6. There is another called Omega 9 but then our bodies can build that one on its own. OK, most people already have enough Omega 3 and Omega 6 in our bodies from all that they eat but still, their health problem persists. Why? It is simply because the Omega 6 to Omega 3 ratio is at a dangerous level. A person has got to have about 4:1 ratio but most people overshoot it and they have around 20:1 or even more. This is because Omega 6 can be found in nearly every type of food. But Omega 3 is more scarce.
To achieve the 4:1 Omega 6 to 3 ratio, the only way is to do a research on the foods that contain lots of Omega 6 and reduce them from your diet. And then take those Omega 3-rich foods such as Cod Liver Oil, Fish, Bananas, etc...