While many sunscreens block both UVA and UVB rays, they fall into two separate categories: chemical sunscreen and physical sunscreen (often known as mineral sunscreen). Zinc oxide and titanium dioxide sunscreens fall into the latter category.
UV (ultraviolet) rays from the sun come in three different wavelengths: UVA, UVB, and UVC. UVA and UVB rays are the most dangerous, as UVC, fortunately, is stopped by the earth’s atmosphere before it ever makes it down to your skin.
UVA rays: UVA rays deeply penetrate the skin, reaching far beyond the dermis—the skin’s thickest layer. This type of UV radiation can cause aging and wrinkles.
UVB rays: UVB rays are shorter and burn the surface of your skin, only reaching the most superficial layers. These initially lead to sunburns and, over time, cause skin cancer.
It’s essential that you use a broad-spectrum sunscreen that provides protection against both UVA radiation and UVB radiation to protect your skin from both photoaging and sun damage.
Countless dermatologists recommend physical sunscreen over chemical.
Chemical sunscreen: Chemical sunscreen is exactly what it sounds like—a mixture of chemicals that come together to block UVA and UVB rays. These ingredients are tasked with degrading or deactivating sunlight, creating a chemical reaction that transforms UV rays into heat, which is then released from the skin.
Physical sunscreen, on the other hand, is made of natural compounds that sit on the surface of the skin. They absorb and deflect sunlight so that UV radiation doesn’t penetrate the epidermis. These ingredients act similarly to aluminum foil or a mirror, keeping sunlight from penetrating deeply. Sunscreens with zinc oxide and titanium dioxide fall into this category. These are the only FDA-approved physical UV filters for sun protection.
Titanium Dioxide Benefits
Titanium dioxide is derived from—you guessed it—titanium. It’s a natural mineral that is used in sunscreen and cosmetics to whiten, thicken, and lubricate, all while offering protection against the sun.
Invisible to the naked eye: It’s typically scaled down much smaller, between 10 and 100 nanometers, making it less noticeable on the skin. This makes it a good choice for those with darker skin, as it doesn’t leave an opaque layer.
Non-comedogenic and gentle on skin. It’s extremely gentle, making it a great choice for those with sensitive skin.