10% Zinc Oxide, Real Extra-Protection Against Sun Aging
A highly protective sunscreen at a SPF >40 with good UVA protection. Zinc Oxide put in microfine form to make it transparent yet retain its sunblock property. Strong stay-on properties making it long lasting as suppose to other non-stay on sunscreens, which only last half an hour in very strong sunlight.
Sunlight contains UVA and UVB, where UVA is the energy which causes Freckles and aging on the skin. SPF only tells how strong a sunscreen is against UVB, it does not tell you how strong it is against the skin aging UVA. The best substance to block UVA remains to be Zinc Oxide. At 10% it has strong UVA protection. Microfine treatment of Zinc Oxide makes them look transparent.
Even with Zinc Oxide, short duration sunscreens only last 1/2 an hour under very strong sunlight. Waterproof/long duration sunscreen can in general last up to 4-5 hours under very strong sunlight.
Zinc Oxide and Mexoryl can protect the whole spectrum of wavelengths given by UVA, while Titanium Oxide/Dioxide does not have total wavelengths protection. Mexoryl is a chemical sunscreen where the sunlight oxidizes it instead of the skin, so it can be used up. Zinc Oxide is a barrier sunscreen where it blocks UVA.
However, Zinc Oxide at 10%, with ‘long duration’ properties can make it rather ‘sticky’.
My response to this remains that it is a trade off for good protection in the long run in terms of anti-aging, and especially after laser procedures where higher protection against sunlight is needed. To prevent millia or acne formation, evening or daytime ‘Fruit Acids’ such as PHA or AHA can be used beforehand.