Lutein is the principal carotenoid concentrated in the macula, the central area of the retina responsible for vision. Lutein and companion carotenoid zeaxanthin work in synergy to provide nutritional support to our eyes and skin* – the only organs of the body directly exposed to the outside environment. Their primary role is to provide antioxidant protection against sunlight-induced free radical damage.* Natural Factors uses LuteinRichTM – a naturally-sourced lutein and zeaxanthin derived from marigold petals. LuteinRich is non-irradiated and non-GMO.