UV Filter
UV Filter — an ingredient added to sunscreen that absorbs or reflects ultraviolet radiation to reduce how much reaches the skin. UV filters are the functional actives responsible for a product's SPF and broad-spectrum protection, and they are broadly grouped into organic and inorganic types.
Key points
- UV filters protect skin by absorbing, scattering, or reflecting ultraviolet radiation before it penetrates.
- They are divided into organic (carbon-based) filters and inorganic (mineral) filters like zinc oxide and titanium dioxide.
- Broad-spectrum protection requires filters that cover both UVA and UVB wavelengths.
- Approved UV filters and their permitted concentrations vary by country and regulatory region.
Frequently asked
What is the difference between UVA and UVB protection?
UVB rays mainly cause sunburn and are the primary driver of SPF ratings, while UVA rays penetrate deeper and contribute to aging; broad-spectrum filters address both.
Are UV filters the same everywhere in the world?
No, the list of approved UV filters and their allowed concentrations differs between regulatory regions such as the US, EU, and Asia.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
