What Is Mineral Sunscreen, and How Is It Different from Chemical SPF?
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As is the case with many skin care products, the sunscreen market is vast and overwhelming. From organic and vegan formulas to lotions and sprays, as well as iterations available from both familiar drugstore brands and high-end labels, it can be difficult to figure out which SPF is right for you. Ultimately, the goal of your purchase is to prevent skin cancer and sun damage—so what's the most effective, conscious choice you can make? Often, this decision comes down to choosing to wear either mineral sunscreen or chemical sunscreen. While both of these lotions will help protect you from damaging UV rays, their differences lie in their ingredients, functionality, and the way they generally appear on your skin. While certain aspects of mineral SPF can make it a more ideal form of sun protection for both you and the environment, it's important to remember that when it comes to your health, you can't go wrong either way.
"When choosing a sunscreen, I always tell my patients that the best sunscreen is the one you wear regularly," says Dr. Jason Rizzo, MD, PhD, a clinical professor of dermatology at University at Buffalo. "It needs to be broad-spectrum, water-resistant, and have an SPF of 30 or higher." Beyond that, it's largely up to your personal preferences and needs. "I encourage patients to experiment with different brands and formulations to find the product that feels and looks best on their skin, since this will foster compliance with regular use," Dr. Rizzo continues. To help ensure you wear the best sunscreen for your health on a daily basis, we asked the experts how mineral sunscreen works and what makes it different from other SPF iterations.
The Difference Between Mineral and Chemical Sunscreen
The biggest distinctions between mineral and chemical sunscreens are their active ingredients and how they function to protect your skin. A mineral sunblock's active ingredients are, as you'd likely guess, minerals—specifically zinc oxide, titanium dioxide, or a combination of both, explains Dr. Robin Schaffran, chief dermatologist and co-founder of BalmLabs. Mineral sunscreens are considered to be physical "blockers" of UV light. "When they are applied to the skin, they physically reflect UV rays," Dr. Schaffran explains. Chemical sunscreens, which rely on chemical ingredients such as octinoxate, homosalate, octisalate, avobenzone, or oxybenzone, instead protect the skin from UV ray damage by absorbing UV light—not reflecting it.
You may see labels boasting phrases like "broad-spectrum protection," "UVA rays," and "UVB rays" when wandering drugstore aisles. These terms are related to differences between the two sunscreen types and the different rays that can potentially cause skin cancer. "All mineral sunscreens provide broad-spectrum protection against UV radiation," Dr. Rizzo explains, which means mineral SPFs can block both UVA and UVB waves from the sun. Absorbent chemical sunscreen, however, is more often formulated to only protect the skin from UVB waves. Dr. Rizzo suggests checking labels for broad-spectrum protection before purchasing a formula to ensure you get the most out of the product.
This differentiator is easier to understand when you think back to previous times you've spent in the sun, says board-certified dermatologist Erum N. Ilyas, MD, MBE, FAAD. "Have you ever said to yourself, I wore sunscreen and still got a sunburn?" the AmberNoon founder asks. If so, you were likely wearing chemical SPF. "Once the chemical sunscreen maxes out its ability to absorb light, the rest of the UV rays overflow to your skin," she explains. Meanwhile, because mineral sunscreen blocks UV rays, wearing zinc or titanium oxide functions like a shield to prevent your skin from absorbing any of that light in the first place.
Who Should Use Mineral Sunscreen
Both mineral and chemical sunscreens are safe and offer necessary protection. Because of their chemical-free formulas, however, mineral sunscreens may be better suited for patients with sensitive skin and photosensitivity disorders, Dr. Rizzo affirms. These sunscreens are known to have lower irritant rates and to cause a smaller number of allergic reactions. Dr. Corey L. Hartman, founder of Skin Wellness Dermatology, adds that people with rosacea and eczema, as well as those prone to allergic contact dermatitis, should also use mineral sunscreen to avoid irritation.
Another aspect of the chemical versus mineral sunscreen discussion is still up for debate: Specifically, how chemical absorbers and the potential endocrine disrupting chemicals in formulas may impact the hormones of those wearing chemical sunscreen. Some dermatologists, such as Dr. Ilyas, err on the side of caution. "Given the unclear risk of endocrine disruption with chemical sunscreen ingredients and their potential absorption into the bloodstream, I tend to recommend children and pregnant women use mineral sunscreen products," she says. On the other hand, Dr. Rizzo points out that while many patients have safety concerns about chemical absorbers, "it's important to note that FDA-approved chemical absorbers have been utilized for decades with an excellent safety record." For Dr. Rizzo, the bottom line is that if a patient cannot access or tolerate a mineral sunscreen, then they shouldn't fear applying a chemical lotion, instead: "The use of a chemical sunscreen is a safer option compared to unprotected sun exposure given the well-established carcinogenic effects of UV radiation on the skin." Ultimately, though, it's a conversation for you to have with your dermatologist or primary care physician.
When to Choose Mineral Sunscreen
The most common reason why someone would choose a chemical over mineral sunscreen is because of how the sunscreen looks on the skin. With their thick, pasty texture, mineral iterations often leave a white cast and sticky residue on the dermis. "Traditionally, mineral sunscreens have not been as elegant as chemical sunscreens, especially for people with Brown and Black skin," Dr. Hartman says. "Breakthrough products that provide physical SPF protection for darker skin without leaving a white or iridescent cast are innovations indeed." Dr. Rizzo mentions that advancements in research and design have resulted in somewhat reduced particle sizes and added tints to try to mitigate some of these concerns.
Finally, if you're an eco-conscious consumer, you may choose to stay away from chemical SPFs because of their environmental impact. "Many chemical sunscreens are known to be toxic and damaging to coral reefs," Dr. Rizzo says, "whereas mineral sunscreens are biodegradable and safer for marine life." Specifically, Dr. Rizzo says that the Coral Reef Alliance recommends using "non-nano" mineral sunscreen, formulated with particles larger than 100 nanometers in diameter, because that formula seems to be safer for marine life than smaller particles.