Carotenoids, which are found in highly-pigmented fruits and vegetables, increase visual function and may prevent age-related eye diseases, according to a study in the Journal of Food Science.1
Researchers reviewed findings from various studies on the effects of carotenoids, specifically lutein and zeaxanthin, on visual performance. They concluded that consuming carotenoids could potentially improve vision, citing a particular study that suggests that lutein and zeaxanthin protect the retina and lens and may prevent age-related eye diseases like macular degeneration and cataract.
Stringham J, Bovier E, Wong J, et al. The influence of dietary lutein and zeaxanthin on visual performance. Food Sci. 2009;75(1):R24-R29.