Mineral vs chemical:
the honest guide

Every sunscreen on the shelf works one of two ways. Chemical filters (oxybenzone, avobenzone, octocrylene and friends) absorb into the upper layers of your skin, soak up UV and convert it to heat. Mineral filters — in practice, zinc oxide — sit on the surface and reflect or absorb UV before it reaches you at all.

Both protect you. The differences are in everything around the protection.

Where mineral wins

• It works immediately. Chemical filters need ~20 minutes to bind in; zinc works the second it’s on.
• It stays out of you. An FDA clinical trial found chemical filters in participants’ bloodstreams after a single application — oxybenzone at hundreds of times the agency’s threshold for requiring further safety study. That doesn’t prove harm (regulators still recommend sunscreen use, and so do we), but if you’d rather your sun protection stayed on the outside, that’s mineral.
• Kinder to reactive skin and eyes. The stinging, the watering eyes on a sweaty climb, most “sunscreen breakouts” — that’s typically chemical filters. Zinc is the same ingredient in nappy-rash cream; it calms skin rather than aggravating it.
• It doesn’t slick off into the sea. That rainbow film around you after you paddle out in normal SPF is chemical filter washing off. Oxybenzone and octinoxate are linked to coral bleaching and banned in Hawaii and Palau. Zinc doesn’t dissolve into the water.

Where chemical wins — honestly

• It’s easier to make feel like nothing. Chemical formulas rub in clear and thin with no effort, which is why they dominate the shelf.
• It’s cheap. Mineral formulation done properly costs more.

The catch with mineral has always been the white cast — zinc is a white powder, and lazy formulations look like war paint. Solving that without resorting to nano-sized particles is the hard engineering problem of the category. It’s also the exact problem NEWD exists to solve: a mineral zinc SPF 30 that rubs in clear, in one step, from a pot that lives in a kit bag.

Rule of thumb: if your SPF lives in a bathroom cabinet, chemical is fine. If your skin is out in it every day — sweating, swimming, squinting — mineral is the one built for the job.

What to look for on a label

• Zinc oxide as the only UV filter (not blended with chemical filters as a topper).
• Non-nano if ocean life or particle size matters to you.
• Broad spectrum — UVA protection is what stops the aging, not just the burning. (More on that here.)
• Fragrance-free — fragrance is the most common irritant in skincare and it does nothing.