zeaxanthin

Zeaxanthin is a carotenoid pigment belonging to the xanthophyll family. It is one of the two major pigments that make up the macular pigment of the human retina, the other being lutein. Chemically, zeaxanthin has the molecular formula C40H56O2 and features hydroxyl groups at each end, making it a fat-soluble, oxygen-containing carotenoid. It occurs widely in nature, especially in leafy greens, yellow and orange fruits, vegetables, and in eggs.

In the eye, zeaxanthin helps protect retinal tissue by filtering blue light and acting as an antioxidant, scavenging reactive oxygen species generated by light exposure. This protective role is primarily associated with the macula, the central region of the retina responsible for sharp vision.

Dietary sources of zeaxanthin include kale, spinach, other green leafy vegetables, corn, yellow and orange peppers, and eggs. Because zeaxanthin is fat-soluble, its absorption is enhanced when consumed with dietary fat. Cooking and processing can affect carotenoid content and bioavailability.

Research on zeaxanthin and eye health has yielded mixed results. Observational studies associate higher macular pigment density with reduced risk of age-related macular degeneration (AMD) and cataracts, while randomized trials of zeaxanthin-containing supplements show varying effects on disease progression and visual outcomes. There is no universally established daily allowance for zeaxanthin in many countries; intake typically comes from a diet rich in fruits and vegetables, and supplements are available but should be used under medical guidance, especially for specific populations.