Lutein and Zeaxanthin: Health-Friendly Nutrients

Abstract

Carotenoids are essential fat-soluble nutrients that are important components of a healthy diet. Among the carotenoids, lutein and zeaxanthin are two of the most abundant carotenoids found in the diet. Humans cannot synthesize lutein or zeaxanthin de novo; therefore, the diet is the sole source of these compounds in the human body. These two carotenoids are present in high amounts in green leafy vegetables, and in chicken egg yolk. Lutein and zeaxanthin are also found in the free form in spinach and broccoli and as esters in mango, orange, papaya, red paprika, algae, and yellow corn. The macula of the eye is a repository for these two carotenoids. A higher dietary intake of lutein and zeaxanthin has shown to reduce the risk of cataracts and age-related macular degeneration. Lutein and zeaxanthin inhibit lipid peroxidation, a likely factor in the etiology of both retinal and cardiovascular disease. It has long been thought that carotenoid intake also reduces the risk of certain forms of cardiovascular disease, stroke, and cancer. Lutein and zeaxanthin may prevent cellular damage in these conditions by quenching singlet oxygen or neutralizing photosensitizers. The purpose of this article is the scientific literature pertaining to review characteristics, mechanisms of action and food sources of lutein and zeaxanthin, which are related to the health.