Imagine a world where sunscreen doesn’t leave you looking like a ghostly figure, especially if you have darker skin. That’s exactly what UCLA researchers have achieved with a groundbreaking mineral sunscreen that tackles the dreaded white cast problem. But here’s where it gets even more exciting: they didn’t need to invent a new chemical—just a clever tweak in the shape of zinc oxide particles. This simple yet brilliant innovation could revolutionize how we protect our skin from the sun.
For years, dermatologists have emphasized the importance of daily sunscreen use to shield against harmful ultraviolet (UV) radiation, the leading preventable cause of skin cancer—the most common cancer in the United States. Yet, many people, particularly those with darker skin tones, avoid mineral sunscreens because of the chalky, white residue they leave behind. And this is the part most people miss: it’s not just about aesthetics; inconsistent sunscreen use due to this issue can have serious health consequences.
A new study led by UCLA Health Jonsson Comprehensive Cancer Center researchers reveals that changing the shape of zinc oxide particles from round nanoparticles to microscopic four-armed structures called tetrapods can significantly reduce the white cast. These tetrapods, produced using a patented high-temperature flame process, form porous networks instead of clumping together, ensuring even distribution in the sunscreen. In lab tests and controlled skin applications, the new formulation appeared warmer and closer to natural skin tones, without the need for additional pigments or coatings.
But here’s where it gets controversial: while this innovation could encourage more consistent sunscreen use across all skin tones, it also raises questions about why such a simple solution wasn’t explored sooner. Could this have prevented years of frustration and potential skin damage for millions of people? And why are darker-skinned individuals, who are less likely to use sunscreen regularly, often diagnosed with skin cancer at later stages, despite lower incidence rates? These are conversations we need to have.
For AJ Addae, a UCLA chemical biology doctoral candidate and first author of the study, this research is deeply personal. Frustrated by the white cast on his own skin, Addae’s experience fueled his determination to find a solution. ‘The best sunscreen is the one people will actually use,’ he said. ‘If zinc oxide can be made to look better on more skin tones without sacrificing protection, it could help more people protect themselves from the sun’s most dangerous effects.’
Zinc oxide is a powerhouse ingredient in mineral sunscreens, effectively blocking both UVA rays (linked to skin aging) and UVB rays (which cause sunburns and increase skin cancer risk). It’s FDA-approved, safe, and often recommended for sensitive or acne-prone skin. However, conventional zinc oxide particles scatter visible light, creating the unwanted white residue. The tetrapod-shaped particles, on the other hand, reflect light differently, minimizing this issue while maintaining an SPF of around 30—comparable to standard mineral sunscreens.
The findings, published in ACS Materials Letters, highlight a promising intersection of materials science and cancer prevention. While further testing is needed before this technology hits the market, the researchers are already collaborating with UCLA Health’s Skin of Color Clinic to study how these particles interact with the skin microbiome and move closer to real-world applications.
Here’s a thought-provoking question for you: If this innovation succeeds, could it bridge the gap in sunscreen use among diverse populations and reduce disparities in skin cancer outcomes? Let us know your thoughts in the comments below. The future of sun protection might just depend on it.
