R. Stoian
Sun protection is widely regarded as an essential strategy for reducing UV-induced skin damage, photoaging, and skin cancer risk. However, the real-world performance of sunscreen products depends on significantly more than the labelled Sun Protection Factor (SPF). Although SPF is a standardised and legally defined efficacy parameter measured under controlled laboratory conditions, it does not fully reflect consumer use.
This article examines the gap between laboratory-tested SPF values and real-world photoprotection performance, focusing on the interaction between formulation architecture, application behaviour, sensory properties, and environmental exposure. Particular attention is given to factors such as film formation, rheological behaviour, filter distribution, and reapplication compliance, all of which can substantially influence effective protection on skin.
In addition, the article discusses challenges associated with high-SPF formulations, including stability, cosmetic acceptability, and increasing regulatory complexity within the European market. The limitations of erythema-based SPF assessment are discussed in the context of diverse skin phototypes, with specific attention to visible-light-induced pigmentation – an endpoint of growing clinical relevance that is not captured by standard SPF testing. By reframing sun protection as a multifunctional performance system rather than a single numerical value, this article aims to provide a more realistic perspective on sunscreen efficacy and communication.
