Why lutein is important for the eye and the brain

Lutein and zeaxanthin are carotenoids that accumulate in the macula. The macula is a yellow spot near the center of the retina that is responsible of high resolution vision. Macular pigment acts as a natural blue light filter and protects the eye from damage. Macular pigment optical density (MPOD) increases with lutein administration and is related to visual function and to the prevention of age-related macular degeneration. MOPD can be measured non-invasively and has been related to better cognitive performance. Moreover, compositional analyses of centenarian brains have shown that lutein is the main carotenoid in the brain although not in plasma, indicating a preferential accumulation in neural tissues, and that carotenoids status is correlated with some functional outcomes. Carotenoids are present in human milk with higher concentration in colostrum than in transitional and mature milk. Formula fed-infants have less plasma lutein concentration than breast fed infants. Analyses of brain from infants who died during the first year of life showed that lutein is also the predominant carotenoid of brain. Studies in non-human primates revealed that carotenoids are determinant in the formation of the retinal epithelia. In vitro studies showed that lutein stimulates the differentiation of human stem cells to neural progenitor cells. All this findings together, mostly the presence of lutein in breast milk, plasma concentration in breast-fed infants vs. formula fed infants, preferential accumulation in the brain and evidences of influence on the retina and the functionality of the brain signal the importance of the role of lutein and zeaxanthin on visual maturation and brain development