18.03.25 | Ceuticoz Research Team
Sunscreens are designed to shield skin from ultraviolet (UV) radiation, but not all UV rays affect the skin in the same way. UVB rays (280–320 nm) are primarily responsible for sunburn, while UVA rays (320–400 nm) penetrate deeper, triggering oxidative stress, collagen breakdown, and unwanted pigmentation.
UV filters work by either absorbing, scattering, or reflecting UV radiation before it damages skin cells. Chemical filters (like avobenzone or octocrylene) absorb UV energy and convert it into harmless heat. Physical filters (such as zinc oxide and titanium dioxide) scatter and reflect light, offering broad-spectrum coverage.
But here’s the key: while sunscreens reduce UV-induced DNA damage and lower the risk of photoaging and skin cancers, they do not completely prevent tanning. That’s because melanin production — the skin’s natural defense — is stimulated even at lower UV exposures that can pass through filters, especially if sunscreen is under-applied or not reapplied.
Clinical research confirms: regular sunscreen use minimizes pigmentation, uneven tone, and tanning over time, but only when applied generously and reapplied every 2–3 hours.
