Background Previous epidemiological, animal and human data report that lycopene has a protective effect against ultraviolet radiation (UVR)-induced erythema. Objectives We examined whether tomato paste - rich in lycopene, a powerful antioxidant - can protect human skin against UVR-induced effects partially mediated by oxidative stress, i.e. erythema, matrix changes and mitochondrial DNA (mtDNA) damage. Methods In a randomized controlled study, 20 healthy women (median age 33 years, range 21-47; phototype I/II) ingested 55 g tomato paste (16 mg lycopene) in olive oil, or olive oil alone, daily for 12 weeks. Pre- and postsupplementation, UVR erythemal sensitivity was assessed visually as the minimal erythema dose (MED) and quantified with a reflectance instrument. Biopsies were taken from unexposed and UVR-exposed (3 Ö MED 24 h earlier) buttock skin pre- and postsupplementation, and analysed immunohistochemically for procollagen (pC) I, fibrillin-1 and matrix metalloproteinase (MMP)-1, and by quantitative polymerase chain reaction for mtDNA 3895-bp deletion. Results Mean Â± SD erythemal D30 was significantly higher following tomato paste vs. control (baseline, 26Â·5 Â± 7Â·5 mJ cm-2; control, 23 Â± 6Â·6 mJ cm-2; tomato paste, 36Â·6 Â± 14Â·7 mJ cm-2; P = 0Â·03), while the MED was not significantly different between groups (baseline, 35Â·1 Â± 9Â·9 mJ cm-2; control, 32Â·6 Â± 9Â·6 mJ cm-2; tomato paste, 42Â·2 Â± 11Â·3 mJ cm-2). Presupplementation, UVR induced an increase in MMP-1 (P = 0Â·01) and a reduction in fibrillin-1 (P = 0Â·03). Postsupplementation, UVR-induced MMP-1 was reduced in the tomato paste vs. control group (P = 0Â·04), while the UVR-induced reduction in fibrillin-1 was similarly abrogated in both groups, and an increase in pCI deposition was seen following tomato paste (P = 0Â·05). mtDNA 3895-bp deletion following 3 Ö MED UVR was significantly reduced postsupplementation with tomato paste (P = 0Â·01). Conclusions Tomato paste containing lycopene provides protection against acute and potentially longer-term aspects of photodamage. © 2010 British Association of Dermatologists.