The Central Retinal Enrichment Supplementation Trials ( CREST ) aim to investigate the potential impact of macular pigment ( MP ) enrichment , following supplementation with a formulation containing 10mg lutein ( L ) , 2mg zeaxanthin ( Z ) and 10mg meso-zeaxanthin ( MZ ) , on visual function in normal subjects ( Trial 1 ) and in subjects with early age-related macular degeneration ( AMD ; Trial 2 ) .