A "good" fatty acid is eicosapentaenoic acid (EPA), the active ingredient in the fish oil that is widely being used now to treat IgAN and which helps form anti-inflammatory prostaglandins. A recent study of fifteen IgAN patients found they were deficient in certain beneficial fatty acids. Supplementing the diet with fish oil increased plasma levels of certain beneficial fatty acids, such as EPA, and suppressed harmful ones.
I would strong suggest you read Fats that Heal, Fats that Kill by Udo Erasumus. I have just started this book, but he touches on all healing oils and their properties.