|JOHNSON, ELIZABETH - Tufts University|
Submitted to: Advances in Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/2/2017
Publication Date: N/A
Interpretive Summary: Carotenoids are plant pigments that make up the yellow, orange, and red color of fruits and vegetables. In this work, we review the research into a type of carotenoid termed xanthophylls. Xanthophylls are a class of carotenoids commonly found in foods such as green leafy vegetables, corn, pumpkins, papayas, and peppers. Xanthophylls accumulate in the body, and two xanthophylls in particular, lutein and zeaxanthin, are found in high amounts in the brain and eye. Although xanthophylls are not required in the diet to maintain daily human health, they are thought to improve brain and eye health and prevent age-related macular degeneration, cardiovascular disease, and cancer. More research is needed to determine whether xanthophylls prevent age-related chronic disease and by which mechanisms.
Technical Abstract: Xanthophylls are dietary carotenoids found throughout the body and include lutein, zeaxanthin, ß-cryptoxanthin, astaxanthin, and canthaxanthin. Lutein and zeaxanthin selectively accumulate in the macula of the eye and in the brain. Major dietary sources of xanthophylls include green leafy vegetables, corn, pumpkins, papayas, and peppers. Although xanthophylls are not considered essential nutrients and have no dietary recommendations, increased dietary intake is associated with improved visual function and cognitive health and decreased risk of AMD (age-related macular degeneration), cardiovascular disease, and cancer. The Age-Related Eye Disease Study 2 (AREDS2) supports the addition of 10 mg of lutein and 2 mg of zeaxanthin in a supplement to reduce the progression to advanced AMD. Higher concentrations of lutein and zeaxanthin are associated with improved cognitive function; however, further large scale interventions are needed to investigate their role. ß-Cryptoxanthin, in particular, may prevent bone loss and the occurrence of non-alcoholic fatty liver disease (NAFLD). The benefits of xanthophylls are attributed to their antioxidant properties which may minimize oxidative stress that would otherwise lead to inflammation and chronic diseases, such as cancer and cardiovascular disease. Xanthophyll research will likely continue as the human lifespan increases along with the occurrence of chronic disease.