Sulforaphane as a Photoprotective Agent Against UV-Induced Skin Damage and Carcinogenesis: A Scoping Review

Background/Objectives: Ultraviolet (UV) radiation is a major environmental carcinogen responsible for skin damage through oxidative stress, DNA damage, and inflammation. The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway plays a central role in regulating cellular antioxidant defences against UV-induced damage. This scoping review aims to evaluate the potential role of sulforaphane (SFN), a known Nrf2 inducer, in protecting against UV-induced skin damage and photocarcinogenesis. Methods: A literature search was conducted in PubMed and Scopus from inception to 27 January 2026, to identify original experimental studies investigating SFN, glucoraphanin, or broccoli sprout extracts in the context of UV-induced skin damage. Eligible studies included in vitro, ex vivo, in vivo, and human models assessing outcomes related to oxidative stress, inflammation, molecular signalling pathways, and tumour development. Following screening and eligibility assessment, twelve studies were included in the qualitative synthesis. Results: The included studies suggest that SFN exerts photoprotective effects across multiple experimental models. In murine studies, SFN and SFN-rich extracts were associated with a reduction in tumour incidence, multiplicity, and volume following UV exposure. In human studies, topical SFN application reduced UV-induced erythema and induced cytoprotective enzyme expression, although clinical evidence remains limited. Mechanistically, SFN consistently activated the Nrf2 pathway, leading to increased expression of antioxidant and phase II detoxifying enzymes, and was associated with modulation of inflammatory responses and inhibition of MAPK/AP-1 signalling. Emerging evidence also indicates potential effects on UV-induced metabolic and epigenetic alterations. Conclusions: Current evidence supports a potential role for sulforaphane in mitigating UV-induced skin damage through activation of endogenous defence pathways. However, the available data are predominantly preclinical, and further well-designed clinical studies are needed to clarify its efficacy and translational relevance in humans.