Zinc oxide and titanium dioxide are the two mineral sunscreen filters, and the difference that matters most is range. Titanium dioxide works best in UVB, and zinc oxide reaches further into long UVA. Both can leave a white cast. How much depends on particle size, and that's where nano comes in.
I make tallow balms, so before the minerals, here's where my jars stop: a balm doesn't screen UV. It's cosmetic care, not a treatment. Your provider's plan comes first, and by day, so does your sunscreen. Our jars come out in the evening, once the screen's off, and after a day outside I'd reach for Bare Silk ($34 as of October 5, 2026). Our tallow and SPF hub covers that evening hand-off in more detail.
What are zinc oxide and titanium dioxide?
They're the two filters behind the word mineral on a sunscreen label. When a sunscreen's active ingredient is zinc oxide or titanium dioxide, alone or together, the American Academy of Dermatology (AAD) calls it a physical sunscreen. Dermatologists recommend that kind for sensitive skin, the AAD says. The AAD adds that all sunscreens, mineral ones included, form a layer on the skin that absorbs the sun's rays.
Outside sunscreen, the EU's Scientific Committee on Consumer Safety (SCCS) notes that zinc oxide turns up in baby creams and calamine lotion, and in medical plasters and dental cement. Titanium dioxide's other job is color. The FDA calls it a synthetically produced white pigment made from natural ores, and it's allowed in US foods at up to 1% by weight.
What UV range does each one cover?
A 2011 review by Smijs and Pavel puts UVB at 290 to 320 nm, with UVA running from there to 400 nm. The long end, 340 to 400 nm, is UVA1. Titanium dioxide crystals absorb more in the UVB part, they write, while zinc oxide's stronger in UVA1. Paired, the review says, they give broad-band protection.
The FDA's 2021 proposal would require broad-spectrum coverage at SPF 15 and above, and it'd add a long-UVA bar to that test, a UVA I/UV ratio of 0.7 or higher.
| Filter | UV range | Cast | Nano status | Where else it turns up |
|---|---|---|---|---|
| Zinc oxide | More long UVA (UVA1) | Less white | No risk on skin to 25% (SCCS), not for inhalable uses | Baby creams, calamine lotion |
| Titanium dioxide | Strongest in UVB | Whiter | No risk on skin to 25% (SCCS), not for sprays or powders | White pigment, food color |
Why does mineral sunscreen leave a white cast?
A white cast is visible light scattering off the mineral particles on your skin. Smijs and Pavel explain that once particles shrink below about half the wavelength of visible light, the light passes through and they're transparent to the eye. Zinc oxide particles of 200 nm or smaller are virtually transparent, they write. Titanium dioxide whitens more than zinc oxide, because its refractive index, a measure of how sharply it bends light, runs higher. So a non-nano label means bigger particles, and usually more white.
Tinted sunscreens contain iron oxide, the AAD notes, and research shows it helps protect skin from the effects of visible light. That light can increase skin darkening, the AAD says, particularly in darker skin tones. So a tint isn't only cosmetic.
Is non-nano zinc oxide better than nano on skin and in sprays?
On skin, regulators haven't found much difference. The FDA's 2021 proposal declined to rule on nano sunscreens as a class. It found zinc oxide's penetration, whatever the particle size, mostly limited to the upper layers of the stratum corneum, the skin's outer layer of dead cells. For titanium dioxide, it called skin an effective barrier, nano sizes included.
The EU's SCCS reached a similar answer for skin, and it drew a line at anything that could be inhaled. In 2012 it found no risk of adverse effects from nano zinc oxide on skin at up to 25%, and in 2014 it said the same of coated nano titanium dioxide. Neither finding covers sprays. Whatever the filter, the AAD says don't spray near the face or mouth.
Coatings handle a separate issue. In sunlight, reactions at an uncoated particle's surface can make reactive oxygen species, which break down other ingredients. Smijs and Pavel list silica and aluminum oxide among common coatings, and the SCCS's 2014 finding assumes a listed coating that stays stable in use.
Where does the FDA stand on the two minerals?
In September 2021 the FDA proposed that sunscreens with either mineral, or both, at up to 25%, are GRASE. That's FDA shorthand for generally recognized as safe and effective. The same proposal called PABA and trolamine salicylate not GRASE, citing data on safety issues. Oxybenzone and avobenzone were among twelve other filters it proposed as not GRASE because the record lacked data, and it asked for more.
As of October 5, 2026, the mineral part is still a proposal. In a Federal Register notice on September 11, 2026, the FDA finalized only its call on PABA and trolamine salicylate, removing both as sunscreen actives. The agency said it'll take up the rest of the 2021 proposal later.
Which mineral filter should you pick?
For sensitive skin, either one fits the AAD's advice, since dermatologists recommend mineral screens for it. For babies and toddlers from six months, the AAD notes a zinc oxide or titanium dioxide sunscreen may cause less irritation. If long UVA is the worry, I'd look for a zinc oxide sunscreen. If the cast bothers you, zinc oxide whitens less, and a tinted screen's iron oxide adds cover against visible light, which the AAD ties to skin darkening. Whichever you choose, the AAD's bar doesn't change. It's broad spectrum and SPF 30 or higher, plus water resistance and a fresh coat about every two hours outdoors, or after swimming or sweating.
Start with Bare Silk ($34), five ingredients and sixty days to disagree.
Questions we hear
Is zinc oxide or titanium dioxide the better mineral sunscreen filter for sensitive skin?
Either can suit it. The American Academy of Dermatology says dermatologists recommend physical sunscreens, the ones built on zinc oxide or titanium dioxide, for people with sensitive skin. For more long-UVA coverage, I'd pick one with zinc oxide, which absorbs more of that band.
Is non-nano zinc oxide safer than nano zinc oxide?
For sunscreen worn on skin, the evidence so far shows no meaningful gap between nano and non-nano zinc oxide. The EU's consumer safety committee found no risk from the nano form at up to 25%, and the FDA found zinc oxide's penetration mostly limited to the skin's dead outer layer at any particle size.
Should you use a spray mineral sunscreen?
If you do, keep it away from your face so you don't breathe it in. The EU's Scientific Committee on Consumer Safety found no risk on skin from nano zinc oxide or nano titanium dioxide at up to 25%, and neither finding covers sprays that could be inhaled. The American Academy of Dermatology says never spray near your face or mouth, or into the wind.
Can you stir zinc oxide into tallow to make sunscreen?
We don't, and I wouldn't. In the US, sunscreen is an over-the-counter drug, and an SPF number comes from testing the finished product on people, which a homemade jar hasn't had. Zinc oxide stirred into tallow has no tested SPF and no tested broad-spectrum coverage. By day, wear a broad-spectrum sunscreen of SPF 30 or higher, and reapply it about every two hours outdoors.
Go deeper
To take sunscreen off at night, see oil cleansing then tallow. If visible light and dark spots brought you here, our guide to the look of dark spots picks up that thread. If you're new to tallow, start with the beef tallow for skin guide. Mineral vs chemical sunscreen is the wider comparison, tallow and zinc sunscreen is how a zinc screen and a balm share a morning, and tallow and SPF is the hub for every sun question.
Sources
- US Food and Drug Administration (2021). Proposed order OTC000008: amending over-the-counter monograph M020, sunscreen drug products for OTC human use. FDA.
- US Food and Drug Administration (2026). Amending OTC monograph M020: sunscreen drug products for OTC human use, final order OTC000008-1, notice of September 11, 2026. Federal Register 91(175).
- The Scientific Committee on Consumer Safety, SCCS (2012). Opinion on zinc oxide (nano form), SCCS/1489/12, adopted 18 September 2012 and revised 11 December 2012. European Commission.
- The Scientific Committee on Consumer Safety, SCCS (2014). Revision of the opinion on titanium dioxide (nano form), SCCS/1516/13, adopted 22 July 2013 and revised 22 April 2014. European Commission.
- The American Academy of Dermatology, AAD (2025). Sunscreen FAQs, last updated February 11, 2025, on the academy's public education site. AAD.
- US Food and Drug Administration (2024). Titanium dioxide as a color additive in foods, content current as of March 4, 2024. FDA.
- Smijs TG and Pavel S (2011). Titanium dioxide and zinc oxide nanoparticles in sunscreens: focus on their safety and effectiveness. Nanotechnology, Science and Applications 4:95 to 112.
Brian is the founder of Craft Tallow, a small-batch tallow skincare line shipped from Cottonwood Heights, Utah, built on 100% grass-fed suet. Questions? Reply to any email from us; it lands with him.