Sunscreen Filters: Mineral (Physical)
Zinc oxide and titanium dioxide: mineral UV filters that sit on the skin's surface and suit sensitive, redness-prone skin.
mineral sunscreen, physical sunscreen, mineral SPF, inorganic UV filters, zinc oxide, titanium dioxide, CI 77947, CI 77891
Sun protection · Sensitive skin · Redness · Pigmentation & dark spots
What it does
Mineral sunscreens use zinc oxide, titanium dioxide or both as their UV filters. These are chemical compounds too; they are called mineral, physical or inorganic because they are fine particles that stay on the skin's surface rather than dissolving into the formula. Used daily, alongside protective clothing, a hat, sunglasses and shade, they help protect the skin from the UV damage behind sunburn, fine lines and pigmentation, just as organic filters do. UV exposure is also a major cause of skin cancer, so daily sun protection matters, with sunscreen as one part of it.
How it works
Zinc oxide and titanium dioxide particles sit on top of the skin, where they absorb most UV and scatter or reflect some of it. Zinc oxide covers UVB and the full UVA range; titanium dioxide is strongest against UVB and shorter UVA, so the two are often paired. Broad spectrum describes which rays a sunscreen covers, not how long it lasts. No sunscreen lasts all day, and mineral formulas rub and wash off easily, so reapply at least every two hours outdoors, and after swimming, sweating or towelling.
MG says
Sensitive skin types fear not: mineral sunscreens are generally gentler and less irritating, so they're my recommendation for sensitive and redness-prone skin, and during pregnancy and breastfeeding. Zinc-based formulas in particular tend to suit rosacea-prone skin.
Cautions
Mineral filters rarely irritate, but some formulas leave a white cast, especially on deeper skin tones (tinted versions help), and thick zinc-based formulas can feel occlusive on the body in hot weather. Because they sit on the surface, they rub and wash off easily. Avoid inhaling spray and powder formulas; for the face, spray into your hands first and pat on.
Regional notes
Australia: Sunscreens whose main purpose is sun protection, and moisturisers with SPF above 15, are therapeutic goods regulated by the TGA (look for AUST L on the pack). The TGA's 2017 review found that nano zinc oxide and titanium dioxide in sunscreens don't penetrate beyond the skin's outer layer.
United States: Sunscreens are over-the-counter drugs regulated by the FDA, whose 2021 proposed order found only zinc oxide and titanium dioxide generally recognised as safe and effective. Labels may show SPF values above 50, while AU and UK labels stop at 50+.
United Kingdom: Sunscreens are cosmetics, and their UV filters must be on the UK's approved list, as in the EU. Nano filters are labelled “(nano)” in the ingredient list, and nano zinc oxide and titanium dioxide may not be used in sprays that could be inhaled.
