Bioactive Form of Folic Acid Dietary SupplementSource Naturals MegaFolinic is a highly bioavailable source of folic acid that helps the body build healthy red blood cells. It supports healthy brain and neurological development along with healthy cell division. Folinic acid does not require the enzymatic conversion that folic acid does so there is enhanced effectiveness for many people. Research suggests that folinic acid is more bioavailable than folic acid because it is more rapidly converted into L-methylfolate, the form of folate in circulation that can cross the blood-brain barrier.