Essential fatty acids (EFAs) are critical to optimum ocular functioning. EFAs cannot be synthesized by the human body and thus must be obtained from the diet. The omega-6essential fatty acid, linoleic acid, is of particular importance to dry eye syndrome. The body converts linoleic acid into prostaglandin E1 (PGE1) in the following step-wise sequence: linoleic acid, gamma-linolenic acid (GLA), dihomo-gamma-linolenic acid, prostaglandin E1. It is important that omega-3 fatty acids be in balance with the omega-6 fatty acids.