The study demonstrates that supplementation with a combination of lutein, zeaxanthin, docosahexaenoic acid (DHA), and eicosapentaenoic acid(EPA) can result in increased concentrations of lutein, zeaxanthin, and fatty acids in plasma and a significant improvement in the optical density of the macular pigment.
Carried out over a 12-month period, the randomized, double-blind, placebo-controlled, parallel clinical trial took place at Friedrich Schiller University Jena, Germany. A total of 172 individuals with nonexudative (dry form) AMD were recruited. The individuals were randomly divided as follows: placebo group, group 1 (a capsule containing 10 mg of lutein, 1 mg of zeaxanthin, 100 mg of DHA, and 30 mg of EPA administered each day), and group 2 (same substances but twice the dose used in group 1). The researchers evaluated the effects of the supplementation on the plasma xanthophyll concentrations and fatty acid profiles, antioxidant capacity in plasma, and optical density of the macular pigment.
The researchers found that the concentrations of the administered carotenoids in plasma as well as the optical density of the macular pigment increased significantly in the groups randomized to receive supplementary macular xanthophylls and omega-3 LC-PUFAs after 1 month of intervention and remained at this level through the end of the study. Use of the double dose resulted in a beneficial alteration of the fatty acid profile in the plasma of patients with AMD in comparison with the dose in group 1. The lipophilic antioxidant capacity in plasma was significantly elevated with the intervention.
They concluded that "A supplement containing a fixed combination of lutein, zeaxanthin, and omega-3 LC-PUFAs during 12 months significantly improved plasma antioxidant capacity, circulating macular xanthophyll levels, and the optical density of the macular pigment."