Lycopene not in pill, nor in natura has photoprotective systemic effect

Abstract

Carotenoids are endogenous antioxidant agents. It has been reported that oral lycopene reduces immediate erythema induced by ultraviolet B radiation. The objective was to evaluate and compare the photoprotective effect of lycopene in capsule and tomato paste. This was an interventional, randomized, comparative 10-week study that included 20 subjects, divided in two groups: 10 for capsule and 10 for tomato paste intake. Blood samples were collected for serum lycopene dosage by high-performance liquid chromatography. Chromatometer was used to measure minimal erythematous dose 24 h after only ultraviolet B irradiation and the variation of color a (maximum erythema, 24 h after irradiation compared to normal skin). Evaluations were made at baseline and after 4, 8, and 10 weeks. Data were analyzed by ANOVA with repeated measures. Three subjects dropped out after 4 weeks. Serum lycopene demonstrated great variability; significant, higher levels for tomato after 4 weeks (p = 0.027) as compared to capsule and significant increase along the study just for tomato (p = 0.044) were detected. No visual change for minimal erythematous dose was observed in all evaluations, for both groups. Chromatometer measures showed no difference in the mean of minimal erythematous dose at baseline between groups. Slight variation of color a after 10 weeks was observed [marginally significant (p = 0.054)], with a tendency to be greater for capsule use [marginally significant (p = 0.066)] and no adverse effects. Lycopene regular intake was safe and demonstrated no effect for systemic photoprotection against ultraviolet B; no correlation with serum lycopene was detected.