title: Skin lycopene is destroyed preferentially over beta-carotene during ultraviolet irradiation in humans.
abstract: This placebo-controlled study examined in healthy women the effects of ingestion of a single large dose of beta-carotene (120 mg) on the concentrations of beta-carotene and lycopene in plasma and skin, and the effects of UV light exposure on the concentrations of beta-carotene and lycopene in the skin. Ingestion of beta-carotene increased plasma beta-carotene concentration by 127%, from 0.26 +/- 0.06 (mean +/- SEM) to 0.59 +/- 0.07 mumol/L after 1 d, and the level remained elevated at 0.54 +/- 0.11 mumol/L after 5 d. beta-Carotene in skin, analyzed after 6 d, increased by 23%, from 1.41 +/- 0.74 to 1.74 +/- 0.72 nmol/g. beta-Carotene ingestion had no effect on the lycopene concentrations of plasma (0.37 +/- 0.11 mumol/L) or skin (1.60 +/- 0.62 nmol/g). A single exposure of a small area of one volar forearm to a dose of solar-simulated light (three times the individually determined minimal erythema dose) resulted in 31 to 46% reductions in skin lycopene concentration compared with an adjacent non-exposed area. The same UV dose did not result in significant changes in skin beta-carotene concentration. We conclude that a single 120-mg dose of beta-carotene increases plasma and skin beta-carotene concentrations and has no effect on plasma and skin lycopene concentrations. The amounts of lycopene in plasma and skin are comparable to or even greater than those of beta-carotene. When skin is subjected to UV light stress, more skin lycopene is destroyed compared with beta-carotene, suggesting a role of lycopene in mitigating oxidative damage in tissues.
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Ribaya-Mercado
authors.forename: M
authors.initials: M
authors.lastname: Garmyn
authors.forename: B A
authors.initials: BA
authors.lastname: Gilchrest
authors.forename: R M
authors.initials: RM
authors.lastname: Russell
mesh_terms: D000284:Administration, Oral; D000368:Aged; D002338:Carotenoids / Q000008:administration & dosage / Q000032:analysis* / Q000097:blood; D005260:Female; D006801:Humans; D000077276:Lycopene; D008875:Middle Aged; D012867:Skin / Q000737:chemistry / Q000378:metabolism / Q000528:radiation effects*; D014466:Ultraviolet Rays; D019207:beta Carotene
chemical_list: D019207:beta Carotene; D002338:Carotenoids; D000077276:Lycopene