Titanium Dioxide

Mineral UV blocker that sits on skin surface.

Also known as: TiO2, CI 77891, titanium oxide; same name in INCI.

What it is

Titanium dioxide is a naturally occurring mineral oxide that works as a physical (mineral) sunscreen. It sits on the skin surface and reflects and scatters both UVA and UVB rays before they penetrate.

What it does

Provides broad-spectrum UV protection by creating a physical barrier that deflects sunlight away from skin. Unlike chemical sunscreens, it does not absorb into the skin or convert UV energy to heat. It begins protecting immediately upon application and is photostable, meaning it doesn't degrade in sunlight.

The evidence

Strong clinical evidence supports titanium dioxide as an effective broad-spectrum UV blocker; it is FDA-approved and recommended by dermatologists. Multiple studies confirm its safety profile and efficacy at concentrations typically 5–10% in sunscreen formulations.

Best for

All skin types, especially sensitive, reactive, and eczema-prone skin; ideal for those who cannot tolerate chemical sunscreens or have a history of photosensitivity.

Pairs well with

Zinc oxide (complementary mineral blocker for enhanced UVA coverage); silicones and oils (improve spreadability and reduce white cast); antioxidants like vitamin E (add photoprotection).

Use cautiously with

No major conflicts; however, nano-sized particles may require careful formulation to avoid settling or uneven coverage. Avoid combining with ingredients that promote photocatalytic activity if using in leave-on products.

Cautions

Micronized or nano-sized titanium dioxide particles have raised theoretical concerns about skin penetration, though current evidence suggests intact skin acts as an effective barrier; use non-nano grades for extra caution. May leave a white cast on darker skin tones; formulation with silicones or iron oxides can minimize this.