EFA’s belong to two types or families of fats. The parent to the family line of omega-6 fats is Linoleic Acid (LA). The parent EFA of omega-3 fats is Alpha Linolenic Acid (ALA). The body uses enzymes to synthesize several EFA derivatives and EFA derived hormones called eicosanoids from these parent fat molecules. Eicosanoids control nearly every important physiological function worth talking about.
If we are eating good sources of the omega 6 and omega 3 families of fats and as long as our metabolic enzyme systems are working in good order, we can transform the saturated fats we eat into the unsaturated fatty acids we need. The EFA derivatives that are so important to the vital functions of the body can be converted from plant sources or can be gotten directly from animal and fish foods.
The omega 3 and 6 fats that we actually use at a metabolic level are arachidonic acid (AA), an omega-6 fat, and eicosapentanoic acid (EPA) and docosahexanoic acid (DHA), both omega-3 fats. AA is relatively high in red meat. EPA and DHA are found in fish and fish oil products, less so in vegetal sources like blue -green algae products.
It is estimated that the ideal ratio of cholesterol lowering foods that contain healthy fats should be about 2:1, or 2 parts omega-6 to1 part omega-3. The evidence is strong that our early ancestors ate a diet similar to this ratio. For instance, fat from wild game contains about equal amounts of the 2 types of EFA’s. The average found in today’s modern western diet is more like 10:1 and for some of us may approach 20:1. This is too much N-6 compared to N-3.
Food that lowers cholesterol for the better restores the natural and more traditional balance of dietary fats. One way you can get more omega-3 fat in your diet is to take flax seed oil. If your (desaturation and elongation) enzymes are working efficiently, the body converts the ALA in flax to the usable forms EPA and DHA just fine.