A powerful antioxidant duo plays an important protective role against eye damage. But did you know their power may extend far beyond what our eyes can see?
Lutein and zeaxanthin, antioxidant carotenoids, are known as the “eye vitamins.” They’re believed to filter harmful high-energy blue wavelengths of light like ultraviolet rays in sunlight, protecting eyes from damage.
Evidence from many research studies over the past couple of decades, particularly a large-scale US National Eye Institute study, point to a positive role of lutein and zeaxanthin in preventing or slowing down age-related macular degeneration and cataracts.
In past research, scientists have discovered the role of oxidative stress in the development of amyotrophic lateral sclerosis (ALS). Though research is preliminary, scientists are now examining the impact of antioxidant nutrients like carotenoids, including lutein, on ALS.
In a large investigation of data from five large prospective study groups across the US, researchers recently found that a greater total carotenoid intake, and especially beta-carotene and lutein, may help prevent or delay the onset of ALS.
Because lutein is known to be the major carotenoid in human brain tissue, several studies have been able to show a positive association between greater lutein status and better cognitive function in older adults.
A recent study in younger adults has also pointed to a positive correlation between higher lutein intake and better cognitive function. The study, published in Frontiers in Aging Neuroscience, included 60 adults between 25 and 45. The results suggested those with higher lutein levels were able to engage more cognitive resources to complete assigned tasks.
Laboratory research has shown some interesting results when lutein and zeaxanthin were used to treat cells from patients with coronary artery disease (CAD). The anti-inflammatory properties of these carotenoids were the catalyst for the experiment.
Because chronic inflammation often remains a higher risk even in those who are receiving treatment for CAD, scientists first tested a blood level marker for inflammation called interleukin-6 (IL-6) in 193 patients with CAD and found an association between higher levels of lutein and lower levels of IL-6.
They then treated cell cultures from these patients and found that lutein specifically reduced the cells’ inflammation activity, or IL-6 levels, suggesting that patients with CAD may improve their immune system with increased intake of lutein.