Actives glossary

Titanium dioxide

The second mineral filter, usually a supporting act to zinc oxide in a tinted or sheer formula.

INCI name
Titanium Dioxide
Also called
TiO2, mineral filter
Family
UV filter
Range seen on labels
1% to 10% in United States sunscreens
Sits well with
zinc-oxide
Needs care with
No common conflict note

Titanium dioxide covers UVB and the shorter UVA wavelengths, with less reach into long UVA than zinc oxide. In practice it appears alongside zinc rather than instead of it, and it contributes much of the whitening in a mineral formula.

Reading a combined filter load

Two sunscreens can both say “mineral” and carry very different totals. In our sunscreen set the combined mineral load runs from 10% in one product to 21% in another, and the split between the two filters differs even where the totals are close. Both figures are on the Drug Facts panel, which makes this the one category where a reader can do this comparison unaided.

The tint question

Iron oxides are frequently added to mineral sunscreens to offset the cast titanium dioxide leaves. They also add visible light protection, which is relevant to pigmentation. That is a formulation benefit that no SPF number describes.