LA and ALA are precursors for the synthesis of very long chain polyunsaturated FAs (VLC-PUFAs), 20- or more carbon-long FAs that contain at least 3 double bonds in cis-position. PUFAs are classified as omega-6 (n6) or omega-3 (n-3) depending on the position of the first double bond counted from the methyl end. Omega-3 PUFAs such as eicosapentaenoic acid (EPA) (C20:5) and docosahexaenoic acid (DHA) (C22:6) modulate membrane fluidity and permeability.