If you've shopped for mineral sunscreen, you've probably seen the words "non-nano zinc oxide." But what exactly does that mean?
The answer comes down to particle size.
What Is "Nano"?
In science, a nanoparticle is generally defined as a particle measuring less than 100 nanometers in at least one dimension.
For perspective:
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1,000 nanometers = 1 micrometer (µm)
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A human hair is roughly 80,000–100,000 nanometers wide.
Nano zinc oxide was developed to improve the appearance of mineral sunscreen by reducing the white cast that larger mineral particles can leave behind.
Why Does Size Matter?
Changing a material's size can change how it behaves.
Smaller particles interact with light differently, allowing sunscreen to appear more transparent while still providing UV protection.
Scientists have also studied whether nano-sized particles behave differently in biological systems and the environment.
Current research shows zinc oxide nanoparticles have minimal penetration beyond the outermost layer of healthy skin, but researchers continue studying their long-term environmental interactions after sunscreen washes into lakes and oceans.
Why SUNMUD Chooses Non-Nano Zinc
At SUNMUD, we formulate with non-nano zinc oxide because it provides broad-spectrum UVA and UVB protection while aligning with our commitment to ingredient transparency and ocean-conscious formulation.
Although research on nanoparticles continues to evolve, we believe choosing non-nano zinc oxide reflects a precautionary approach that's consistent with our mission.
The Bottom Line
Nano simply refers to particle size—not whether an ingredient is "good" or "bad."
Nano zinc was developed to improve cosmetic appearance, while non-nano zinc provides the same mineral UV protection with larger particles.
At SUNMUD, we've chosen non-nano zinc oxide because we believe simple, transparent ingredients are the foundation of great sunscreen.
Experience broad-spectrum mineral protection with SUNMUD Sunscreen.
References
NOAA. “Sunscreen Chemicals and Coral Reefs.” 20 May 2024, https://oceanservice.noaa.gov/news/sunscreen-corals.html
Olson, Danielle. “The Truth About Corals and Sunscreen.” September 2022, https://ocean.si.edu/ecosystems/coral-reefs/truth-about-corals-and-sunscreen
