The efficacy of sunscreen use for the prevention of skin cancer

Due to the correlation between exposure to ultraviolet radiation and the majority of skin oncology, the utilization of sunscreen, which serves as a barrier against ultraviolet radiation, is emphasized as a crucial measure in the prevention of skin cancers, as well as sunburn and skin photoaging. But how exactly do sunscreens function? They consist of either chemical (organic) or physical (inorganic) compounds that effectively obstruct ultraviolet radiation. Physical sunscreens, such as titanium dioxide and zinc oxide, possess the ability to either reflect or refract ultraviolet radiation away from the skin. Intriguingly, it has been observed that when a sunscreen with a sun protection factor (SPF) of 50 is applied in real-world conditions, its actual SPF may diminish to 25. Consequently, spray-on sunscreens are considered less preferable compared to their cream-based counterparts. Researchers from Canada have reported that observational studies provide evidence supporting the efficacy of sunscreens in preventing photoaging manifestations, including wrinkles, telangiectasia, and pigmentary alterations caused by ultraviolet radiation. Additionally, a comprehensive study conducted in Australia revealed a notably reduced incidence of actinic keratoses (a precursor to squamous cell carcinoma) among participants who were randomized to regularly use sunscreen, in comparison to the control group who used a nonactive base cream, over the course of one summer season. Overall, the evidence available affirms the preventive role of sunscreens in combating skin cancer.