Lutein and zeaxanthin are known key carotenoids for eye health, filtering out harmful high-energy blue wavelengths of light and helping to protect and maintain cells comprising the eye. The human body does not make enough of either nutrient, so we must get them from supplements or food sources such as kale, spinach, collard greens, turnip greens, corn, green peas, broccoli, romaine lettuce, green beans and eggs.
Researchers from the University of Georgia, in Athens, investigated the relationship between levels of lutein and zeaxanthin and cognitive function. They measured the levels of each nutrient in the retinas of 43 older adults with a mean age of 72 and asked that the subjects learn and recall pairs of unrelated words. The study found that those with higher levels of both nutrients did better on the test, suggesting that the enhanced neural efficiency that comes from consuming these nutrients leads to better brain function.