Nano Zinc Oxide: Is It As Safe (And Effective) As Regular Zinc Oxide?

by Gio
nano zinc oxide particles in sunscreen

Remember the good old days when you could immediately tell if someone was using sunscreen?

That white nose gave the hunky lifeguard away before you could even see his bright red pants.

Those days are over.

Now we have the technology to make zinc oxide and its BFF titanium dioxide – the rascals responsible for the white cast and chalky texture – so small, you won’t be able to see them sitting on your face.

Intrigued? Read on:

Why Should You Use Zinc Oxide?

Cos it’s freaking awesome, my friend.

  1. It provides broad spectrum protection ON ITS OWN: no more need to use four or five ingredients to be fully protected, yay!
  2. It’s very gentle on the skin: it’s one of the very few UV filters that won’t irritate even sensitive skin or cause allergies. Double yay!

But, the white cast and thick consistency are serious downers. It’s not unusual to get all excited about the gentleness of zinc oxide only to give it up for life when you realise how user-unfriendly it can be. Bummer!

Enter nanoparticles (aka microparticles), the new technology I was talking about…

Related: Why Zinc Oxide Is The Best UV Filter Ever

What The Heck Are Nanoparticles?

Tiny particles. Duh!

Nanotechnology drastically shrinks the size of a substance so that it is much, much smaller than its non-micronized original.

Of course, when something becomes that tiny, it also starts to behave differently. Micronized zinc oxide:

  • Doesn’t leave a white cast behind (those tiny molecules are practically invisible to the naked eye!).
  • Has a lightweight texture that makes it so easy to apply and comfortable to wear.

So easy and comfortable, the first time I used a sunscreen with zinc oxide nanoparticles, I almost didn’t believe it really had zinc oxide. It felt exactly like one of those lightweight Asian sunscreens we all love so much minus the potentially irritating synthetic UV filters and alcohol that give them their weightless textures.

The best of both worlds basically…

Or not?

Are Zinc Nanoparticles Safe?

Here’s the deal: the smaller something is, the easier it can penetrate the skin.

Zinc oxide is a pretty big molecule. But when you shrink it down to an invisible size, there’s a chance it can penetrate your skin, get into your bloodstream, and cause all sorts of problems.

IF it gets in there. But, does it?

Nope. Like all UV filters, zinc oxide needs to stay on the surface of the skin to protect it from the sun. If it penetrated the skin, then UV rays would get through too and cause all sorts of havoc. In other words, an UV filter that penetrates skin is useless.

That’s why cosmetic chemists often coat zinc oxide nanoparticles with silicones and other occlusive agents. This way, these nanoparticles stay where they should and are needed – on the surface of your skin.

Want all the benefits of zinc oxide minus the white cast and greasy texture? Go nano. It's safe.Click to Tweet

The Real Danger: Nanoparticles in Spray Sunscreen

Nanoparticles can’t get in through your skin. Phew!

But, they can get in through your nose. When you apply spray suncreen, you’ll likely breathe some of those nanoparticles in. They end up in your lungs and may damage them.

So, stay away from spray sunscreens with nanoparticles.

And while you’re at it, stay away from all spray sunscreens, period. I know they’re very convenient to use, but it’s so hard to tell if you’ve missed a spot. Until that spot gets a bad sunburn. Ouch!

Related: Why I Don’t Use Spray Sunscreen (And You Shouldn’t Either)

The Bottom Line

If you’ve always wanted to jump on the zinc oxide bandwagon but were put off by the white cast and greasy texture, nanoparticles are the way to go. They’re safe. Just don’t get your dose from a spray sunscreen.

Have you ever used sunscreens with nano zinc oxide? Share your thoughts in the comments below.



Janessa August 9, 2016 - 5:49 am

I was curious about this just last week! I was browsing through the beauty isle of a health food store and there was this microionized zinc sunscreen. Thanks so much <3 your blog is wonderful.

Gio August 10, 2016 - 10:40 am

Janessa, what a coincidence! Glad to be of help. 🙂

Barbara August 9, 2016 - 9:17 am

Great article. 🙂

Gio August 10, 2016 - 10:40 am

Barbara, thank you!

Cheryl August 9, 2016 - 4:55 pm

Love zinc oxide as a sunblock! I haven’t yet seen one that has the tell-tale brackets of (nano) in the ingredients list though! Have you?…

Gio August 10, 2016 - 10:43 am

Cheryl, they were quite popular a few years ago, but these days it’s mostly small brands that use them. Everyone else has been scared off. Badger Balm for example states on its website that nano zinc oxide is safe, but has stopped using it because its customers were afraid of it. And this even though the EWG claims they’re safe too! Isn’t it ironic that the only time the EWG gets it right, no one listens to it?

Nia August 11, 2016 - 8:12 am

Fab thank you!! I was curious about this as it is always in my mineral foundation and friends had told me it would be absorbed into my skin.
My only complaint is that there’s possibly a reaction with sweat as if I have a hot sweaty face from the gym and try to dust some powder on afterwards – boom, huge red angry sore rash!
Other than that seems great xx

Gio August 11, 2016 - 2:12 pm

Nia, nope, it can’t penetrate your skin so you can tell your friends you can all use it safely. 🙂

Hannah August 13, 2016 - 3:28 am

Ya-TOTALLY! And if it did get into the skin your body would treat nano zinc chances are just like a zinc supplement. Cannot name the study,but I remember it involved a petri dish.

The one thing I’m disappointed about,though,is that the smaller the particle size the smaller the UVA protection,but it does increase the UVB protection.But who really cares,though, about UVB when they’re inside all day? UVB doesn’t go through windows.

Gio August 13, 2016 - 8:17 pm

Hannah, that’s a good point. But I think there are ways to formula a broad spectrum sunscreen with nano zinc oxide. One study I read recommended to mix different size particles of zinc oxide so as to have a formula that’s effective but doesn’t leave a white cast behind.

Olga October 23, 2017 - 5:20 pm

so, is it safe to use the Badger sunscreen that uses Non-Nano Uncoated Zinc Oxide? Will that stay on the surface of your skin and won’t penetrate to your bloodstream?
Thank you so much for advise!

Gio October 28, 2017 - 1:55 pm

Olga, no uncoated zinc oxide won’t penetrate your skin. Zinc oxide needs to stay on the skin to work anyway. If it penetrated your skin, your sunscreen would be useless!

R August 22, 2019 - 11:49 am

Hi Gio!
Do you have any product recommendations for nano zinc oxide sunscreen?

Gio September 14, 2019 - 7:12 pm

R, Skinceuticals uses it, I believe.

Comments are closed.