Mixing mineral and chemical sunscreens to benefit from both? Sounds sensible, but it's not a good idea. We'll explain why in a nutshell in this blog post.
Mineral and chemical sunscreens – essential differences
Mineral sunscreens typically contain zinc oxide or titanium dioxide as UV filters. These substances form a physical barrier on your skin that reflects UV rays. Mineral sunscreens are generally great for sensitive skin types and offer immediate protection as they don't need to be absorbed first.
Chemical sunscreens, on the other hand, contain filters with names that are difficult to pronounce, such as Ethylhexyl Salicylate, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine (Bis-EMT), Diethylamino Hydroxybenzol Hexyl Benzoate (DHHB), Oxybenzone, or Octinoxate. These penetrate the upper layer of the skin, where they convert high-energy UV radiation into lower-energy infrared radiation (=heat). Due to their effect on the skin, they usually need to be applied about 20–30 minutes before sun exposure to fully develop their protective effect.
Mixing different sunscreens – risks and recommendations
In principle, it is not recommended to mix different sunscreens – be they mineral and chemical or products from different manufacturers. This is due to several possible risks:
1. Instability of the formulation
The ingredients of different products can react with each other, which may impair the stability of the formulation.
2. Reduction of UV protection
Mixing can also lead to a reduction in the protective effect against UV rays. In some cases, toxic degradation products may even be formed, which could be harmful to the skin.
3. Possible skin irritations
Reactions between different ingredients can potentially lead to skin irritations or allergic reactions, especially in sensitive skin.
Not using sunscreen at all is not an alternative!
Sunscreen is an absolute must when we spend time outdoors on sunny days. Especially during longer sun exposures, heavy sweating, or after swimming, it is crucial to reapply regularly to maintain protection.
Even if mixing sun protection products is not ideal, it is still much better to use some protection than to forgo it entirely. Inadequate UV protection significantly increases the risk of sunburn, premature skin aging, and skin cancer.
Our recommendation: Reapply with the same sunscreen
To ensure optimal protection, we recommend reapplying regularly throughout the day, preferably with the same sunscreen that has already been used. This way, the formulation and UV protection remain stable, and the skin is continuously protected.
O U R E X P E R T
Dr. med Michaela Hagemann I boep-Founder, Doctor & Mother of 3
