Two separate things are true about this product, and they need separating.
As a sunscreen, it is genuinely very good. Zinc oxide 11%, no chemical filters, and — remarkably for a 100% mineral formula — almost no white cast. It is lightweight, absorbs fast, and sits well under makeup. This is the sunscreen your dermatologist's office actually stocks, and that is not an accident.
On the DNA-repair claim, be careful. ISDIN adds photolyase, an enzyme that repairs UV-damaged DNA. The biochemistry is real — photolyase does repair the specific DNA lesions that UV creates.
But the clinical evidence that this reduces actinic keratoses is weak and mostly funded by ISDIN. The supporting trials are small (30–45 people), several have no control group, and the marketing's headline number is a molecular marker, not a count of actual lesions. The one large independent trial — publicly funded, double-blind, in Brazil — found no difference between sunscreen with photolyase and plain sunscreen.
Here is the honest read: daily SPF 50+ is proven to reduce actinic keratoses and skin cancer. This is an SPF 50+ that people with sun-damaged skin will genuinely wear every day. That alone justifies it. The DNA-repair layer is a promising maybe, not an established fact — and you should not pay extra for it expecting the proven part.