Photoprotective potential of natural products in sunscreens: from UV-filtering mechanisms to skin cancer prevention

Sunlight facilitates photosynthesis in plants and serves as a significant source of Vitamin D for humans. However, excessive sun exposure has substantial adverse consequences, including skin damage, skin cancer, and photoaging. Ultraviolet (UV) radiation is one of the key environmental risk factors for skin cancer, which is the most common type of cancer in the world. Despite the widespread use of synthetic sunscreens to mitigate UV exposure hazards, growing concerns regarding their potential adverse effects on human health, bioaccumulation, and the environment have spurred the exploration of natural product-based alternatives. This review outlines the distinct categories of sunscreens, the adverse effects of UV radiation on humans, and the disadvantages of inorganic and organic sunscreens compared to natural product-based sunscreens. This review gathers evidence from a comprehensive Scopus search (2017–2025) to evaluate the photoprotective, antioxidant, and anti-inflammatory activities of various plant-derived products ideal for sunscreen formulation. We highlight the multimodal mechanism of action of sunscreens in skin cancer prevention and summarize in vitro and formulation data for representative natural products. We discuss formulation strategies to overcome the limitations of natural product-based sunscreens and identify critical gaps, particularly the need for rigorous in vivo and clinical validation and scalable standardization methods. Finally, future prospects are outlined to highlight the stability and efficacy of natural sunscreens as commercially viable, broad-spectrum products that meet customer demands for safety and environmental sustainability.