Marigold, specifically the species Tagetes erecta (commonly called Mexican or African marigold), is widely used as a source of lutein and zeaxanthin—two carotenoids that accumulate in the retina and are known to support eye health. Scientific evidence supports the use of marigold extracts standardized for lutein and zeaxanthin in maintaining eye function and reducing the risk of age-related macular degeneration (AMD). Numerous clinical studies have demonstrated that supplementation with these carotenoids can increase macular pigment density and improve visual performance in both healthy individuals and those with early signs of retinal degeneration. The AREDS2 study, a large-scale randomized controlled trial, found that supplementation with lutein and zeaxanthin (often derived from marigold) can help slow the progression of AMD.

While marigold flowers have also been used in traditional herbal medicine for various purposes, the connection to eye health is almost entirely due to their concentration of these specific carotenoids. The extraction and standardization of lutein and zeaxanthin from marigold is well-established and widely used in the dietary supplement industry. Therefore, the use of marigold for eye health is primarily supported by scientific validation related to its bioactive compounds, rather than traditional use of the whole flower for eye conditions.