Ti
Titanium Dioxide
Titanium Dioxide · Titanium Dioxide (CI 77891) · CI 77891SPF filter
Mineral UV filter. Primarily UVB plus short UVA. Pairs with zinc oxide for full-spectrum coverage.
What it does
Titanium dioxide reflects and scatters UV radiation. It covers UVB and short UVA but leaves longer UVA gaps — modern mineral sunscreens pair it with zinc oxide for full-spectrum protection. Less of a white cast than zinc at the same concentration. Mineral filters are the cautious default during pregnancy, since it's the chemical filters that show measurable systemic absorption.
The evidence, graded
expert consensusSunscreen should sit as a film on top of moisturizer, not be mixed into it. Diluting sunscreen with moisturizer in your hand reduces filter concentration and the labeled SPF no longer applies.Petersen 2014 · Photodermatology, Photoimmunology & Photomedicine ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
TiO2, ci 77891
Pairs worth knowing
Read more
Reading the evidence · 5 minSunscreen for Aging Concerns: The Most Evidence-Backed Step in SkincareIf one skincare claim has the strongest evidence behind it, it's daily sunscreen for aging-related skin concerns. Here is what the research actually shows.How Drop works · 5 minSunscreen Reapplication: Why Every 2 Hours Actually MattersSunscreen wears off faster than most people realize. What happens in those 2 hours, when reapplication matters most, and how to do it over makeup.
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