Ingredients Glossary / Z

Zinc Oxide

A white mineral UV filter that protects against both UVA and UVB, and a gentle choice for sensitive and redness-prone skin.

zinc oxide, CI 77947, ZnO, non-nano zinc oxide, zinc oxide [nano]

Sun protection · Sensitive skin · Redness

    What it does

    Zinc oxide is a white mineral compound, refined to a high purity for cosmetics, used as a sunscreen filter, a skin protectant and a pigment. Along with titanium dioxide, zinc oxide offers minimal risk of skin sensitisation. As a sunscreen, it is effective in providing protection against both UVA and UVB rays. Zinc oxide is used in makeup to impart opacity to products like foundations, particularly powder-based makeup, and its mild soothing action is why it features in barrier creams.

    How it works

    In sunscreens, zinc oxide particles sit on the skin's surface, where they absorb, scatter and reflect UV across the UVB and full UVA range, helping to prevent sunburn. It is one of the most widely used mineral filters: lighter zinc formulas often leave a soft matte finish that suits oilier skin, and they tend to be well tolerated by sensitive and rosacea-prone skin.

    MG says

    Zinc oxide and other mineral sunscreens are wonderful alternatives for those who are sensitive to, or do not wish to use, organic (chemical) filters. Layering one sunscreen over another won't add up their SPFs, so in summer and during high-UV hours choose a single broad-spectrum SPF 50+, apply it generously and reapply at least every two hours, and after swimming, sweating or towelling.

    Cautions

    Zinc oxide rarely irritates. Some formulas leave a white cast, especially on deeper skin tones, although tinted and finer-particle versions reduce this, and thick zinc-based sunscreens can feel occlusive and congesting on the body in hot weather. Avoid inhaling zinc oxide powders or sprays; for the face, spray sunscreen into your hands first.

    Regional notes

    Australia: Sunscreens whose main purpose is sun protection, and moisturisers with SPF above 15, are therapeutic goods (look for AUST L on the pack), while tinted bases and foundations with SPF can be cosmetics.

    United States: US sunscreens are over-the-counter drugs, and zinc oxide is one of only two filters the FDA's 2021 proposed order found generally recognised as safe and effective.

    United Kingdom: In sunscreens, nano zinc oxide must be labelled “(nano)” in the ingredient list and may not be used in sprays that could be inhaled; the same applies in the EU.