title: Photoprotection by dietary carotenoids: concept, mechanisms, evidence and future development.
abstract: Carotenoids are micronutrients present mainly in fruits and vegetables, and they are ingested from these sources with the diet. They exhibit specific antioxidant activity but also influence signaling and gene expression at the cellular level. β-Carotene and lycopene, the colorants of carrots and tomatoes, respectively, are among the most prominent members of this group of lipids, and they are usually the dominating carotenoids in human blood and tissues. Both compounds modulate skin properties when ingested as supplements or as dietary products. There is evidence that they protect the skin against sunburn (solar erythema) by increasing the basal defense against UV light-mediated damage. Their photoprotective efficacy, however, is not comparable to the use of a sunscreen. In vitro data show that also other carotenoids are efficient photoprotectors. Among them are lutein and structurally unusual phenolic polyenes like 3,3'-dihydroxyisorenieratene.
authors.affiliation: Institute of Biochemistry and Molecular Biology I, Faculty of Medicine, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany. wilhelm.stahl@uni-duesseldorf.de
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Stahl
authors.forename: Helmut
authors.initials: H
authors.lastname: Sies
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D002338:Carotenoids / Q000378:metabolism / Q000494:pharmacology*; D019587:Dietary Supplements; D006801:Humans; D014975:Lutein / Q000494:pharmacology; D000077276:Lycopene; D012867:Skin / Q000378:metabolism / Q000528:radiation effects*; D013473:Sunscreening Agents / Q000494:pharmacology; D014466:Ultraviolet Rays / Q000009:adverse effects*; D019207:beta Carotene / Q000378:metabolism / Q000494:pharmacology
chemical_list: C534790:3,3'-dihydroxyisorenieratene; D000975:Antioxidants; D013473:Sunscreening Agents; D019207:beta Carotene; D002338:Carotenoids; D000077276:Lycopene; D014975:Lutein