A supplementation with lutein, zeaxanthin and omega-3 fatty acids seems to significantly improve the processing speed of visual signals, even in young, healthy people.
The randomized controlled trial investigated the potential relationship between increased intakes of zeaxanthin alone (20 mg/day), a combination of zeaxanthin (26 mg/day), lutein (8 mg/day) and mixed omega-3 fatty acids (190 mg/day) or placebo for four months with macular pigment density and visual motor reaction time in 92 young healthy participants (1). The study results showed that participants who received the supplements had significantly increased lutein and zeaxanthin (macular pigment) concentrations in the retina of the eye and an improved visual motor reaction time (about 10%) compared to placebo.
The researchers commented that lutein and zeaxanthin are major carotenoids in the eye but are also found in post-receptoral visual pathways. It has been hypothesized that these pigments influence the processing of visual signals within and post- retina. Increasing macular pigment density – as a biomarker of lutein and zeaxanthin levels in the brain – through supplementation seems to result in significant improvements in visual processing speed, even when testing young, healthy individuals who tend to be at peak efficiency. Visual processing speed is how fast one can look at and process information on a task that does not take any more thinking than noticing the differences or sameness in the objects shown.