Essential Fatty Acids
Intake of omega 3 and omega 6 fatty acids should be balanced, yet the typical American diet tends to contain 14 to 25 times more omega 6
What are these?
There are two types of fatty acids, omega 3 and omega 6. These fatty acids are not produced by our bodies, but our bodies need and use them to make other fatty acids, which is why they are referred to as “essential”.
The three principal omega 3 fatty acids are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
Most omega 6 fatty acids come from vegetable oils, such as linoleic acid (LA). LA is converted to gamma-linolenic acid (GLA) in the body. 
What these do
Both omega 3 and 6 play an essential role in brain function and normal growth and development. Some studies link excess of the linoleic acid form of omega 6 to pain and inflammation.
Omega 3 supplements may interact with drugs that affect blood clotting.
Some types of omega 3s are found in foods such as fatty fish and shellfish. Caution should be used if there is an allergy to fish or seafood. Omega 6 fatty acids can be found in sunflower, safflower, soy, sesame, and corn oils.
The typical American diet tends to contain 14 to 25 times more omega 6 fatty acids than omega 3 fatty acids, while the Mediterranean type of diet tends to contain a better balance. 
Recommended Dietary Allowance (RDA)
Canada’s RDA can be found here.
Molecular Dosage Range
There rarely is a need to supplement with omega 6.
Orthomolecular practitioners may recommend omega 3 supplements at dosages much higher than the RDA based on individual needs. Omega 3 supplements may interact with drugs that affect blood clotting.