Editor’s Note
**Editor’s Note:** This article highlights a promising innovation in sunscreen technology, where redesigned zinc oxide particles aim to reduce the white cast often associated with mineral sunscreens. The development could encourage broader and more consistent use across diverse skin tones, supporting better protection against UV radiation.
Source: University of California – Los Angeles Health Sciences
Scientists have redesigned zinc oxide particles to create a mineral sunscreen that protects against ultraviolet radiation without leaving such a noticeable white cast. The SPF 30 formula could make sunscreen easier and more appealing to use across a wider range of skin tones.
Dermatologists have long recommended daily sunscreen use to reduce exposure to ultraviolet radiation. Too much ultraviolet radiation is the leading preventable cause of skin cancer, which is the most common cancer in the United States.
Despite those risks, many people do not apply sunscreen regularly. One common complaint is that mineral sunscreens containing zinc oxide can leave a noticeable white or gray film on the skin.
A study led by researchers at the UCLA Health Jonsson Comprehensive Cancer Center suggests that the problem could be addressed without creating an entirely new chemical ingredient. Instead, the researchers changed the physical shape of the zinc oxide particles already used in many mineral sunscreens. This could support skin cancer prevention by making mineral sunscreen more appealing and encouraging regular use among people with a wider variety of skin tones.
The potential benefits may be particularly significant for people with darker skin tones. They are often less likely to use sunscreen consistently and are more likely to receive a skin cancer diagnosis at a later stage.
Although melanoma, the deadliest form of skin cancer, is less common among people with darker skin tones, research indicates that they are considerably more likely to die from the disease. One reason is that melanoma is often discovered later, when treatment becomes more difficult.
For first author AJ Addae, a UCLA chemical biology doctoral candidate and cosmetic science entrepreneur, the research grew out of personal experience.
Zinc oxide is widely used in mineral sunscreen because it blocks UVA rays, which contribute to skin aging, as well as UVB rays, which cause sunburn and increase the risk of skin cancer. The U.S. Food and Drug Administration classifies zinc oxide as safe and effective.
Mineral sunscreens are commonly recommended for people with sensitive skin, acne-prone skin, rosacea or those who prefer non-chemical options.
However, standard zinc oxide particles often gather into clumps. This can make sunscreen formulas less stable and cause the particles to scatter visible light, producing the white or gray residue that is especially noticeable on darker skin tones.
The UCLA team investigated whether changing the particles’ structure could prevent that clumping and improve the sunscreen’s appearance.
Most zinc oxide used in sunscreen consists of very small, roughly spherical nanoparticles produced through chemical manufacturing methods. For the new study, the researchers examined much larger particles created through a patented high-temperature flame process. These particles take the form of tiny tetrapods.
When the two types of zinc oxide were used at the same concentration, the sunscreen containing tetrapods reached a sun protection factor (SPF) of about 30. That level of protection is similar to what standard mineral sunscreens provide.
The most visible improvement involved how the particles interacted with light. In laboratory experiments and controlled applications on skin, the tetrapod sunscreen produced a warmer appearance that more closely matched natural skin tones. It did not create the same intense white or gray cast associated with conventional zinc oxide.
The sunscreen technology will require additional testing before it can become commercially available. Still, the researchers say the findings demonstrate how materials science could help address a practical barrier to skin cancer prevention.
The researchers are now collaborating with the UCLA Health department of dermatology, including UCLA Health’s Skin of Color Clinic. They plan to examine how the tetrapod particles interact with the skin microbiome and continue working toward real-world applications.
UCLA researchers found that changing zinc oxide particles into four-armed tetrapod shapes could reduce this effect.
The study was funded in part by the National Science Foundation, the Challenge Initiative at UCLA and a Sigma Xi IFoRE Grant-in-Aid.
Story Source: University of California – Los Angeles Health Sciences
Journal Reference: University of California – Los Angeles Health Sciences. “UCLA scientists develop mineral sunscreen without the chalky white cast.” ScienceDaily. ScienceDaily, 19 July 2026.