Mineral Vs. Chemical Sunscreen: Does It Matter Which You Use?
May 17, 2022 - Katie McCallumThe number of options in the sunscreen aisle can feel overwhelming these days. Several questions seem pertinent.
Does a higher price mean a better product? Do spray sunscreens actually work? What SPF do I need? Why do some say oxybenzone-free and others do not?
And finally: What's the difference between mineral and chemical sunscreen?
What is mineral sunscreen?
Mineral sunscreens, which are also sometimes referred to as physical sunscreens, stay on the surface of the skin and deflect the sun's harmful UV rays.
"The active ingredients in physical sunscreens are minerals, either zinc oxide or titanium dioxide," explains Annie Christenson, a medical aesthetician at Houston Methodist who practices with the ENT specialists. "These minerals cause the sun's rays to bounce off of your skin. They protect from both UVA and UVB rays, meaning that any mineral sunscreen you find will be naturally broad spectrum."
Since these sunscreens protect your skin by sitting on top of it, it's important to apply generously and in even layers to ensure there are no spaces of skin remaining exposed.
"Because sunscreen is highly regulated, it's very easy to tell if you're looking at a mineral sunscreen or not," says Christenson. "Just flip to the back of the box and find the 'Active Ingredients' section. If you see either zinc oxide or titanium dioxide, it's a mineral-based sunscreen."
If it lists active ingredients instead of those, it's a chemical sunscreen.
What is chemical sunscreen?
Chemical sunscreens, on the other hand, contain active ingredients that are absorbed into the skin and prevent damage from the sun by inactivating UV rays through a chemical reaction.
"This reaction does create some heat, but it then dissipates," adds Christenson.
Since chemical sunscreen relies on the skin's absorption of these ingredients, it's important to apply it about 20 minutes before sun protection is required.
"Additionally, be sure to look for a chemical sunscreen that's listed as broad spectrum," says Christenson. "Most are these days, but just be sure to confirm that it states that on the bottle."
What's the difference between mineral and chemical sunscreens?
First, a sunscreen history lesson.
You probably remember the thick white sunscreen worn by people who spent a lot of time in the sun, like lifeguards and surfers. That was the early version of mineral sunscreen.
"Mineral sunscreen has, of course, been used for a long time at the beach and pools," says Christenson. "But once we realized sunscreen needed to be used every day, having a white pasty layer on our faces wasn't desirable. That's when chemical sunscreen was developed and popularized, because it was easier to use every day."
Newer formulations of mineral sunscreens have changed the landscape, however. Now, they can be clear or tinted, both of which blend into your skin.
"Mineral sunscreens are completely different now," says Christenson. "They're much more wearer friendly. It may still look white when it goes onto your skin, but it generally blends right in with no issue."
And with both sunscreen types now offering a similar look — a lack of a look, really — you might be wondering whether you should ditch the chemicals and switch to a mineral sunscreen.
Does it matter which you choose?
In reality, the best sunscreen to use is the one that you'll actually put on your face every day — as long as it's a broad spectrum lotion with an SPF of 35 or higher. It's also the one that you'll be sure to slather on all of your exposed skin when you plan to be out in the sun, even if it's cloudy, even if it's cold.
Sun safety, which includes wearing sunscreen, is essential to preventing not just painful sunburns, but skin cancer. The relationship between sun overexposure and skin cancer is well documented.
Both mineral and chemical sunscreens are effective forms of sun protection when used properly, but when it's possible, there may be a case for a mineral-based sunscreen over a chemical one.
Both zinc oxide and titanium dioxide, the two active ingredients found in mineral sunscreens, are generally recognized as safe and effective (GRASE) by the FDA. The designation allows certain OTC drug products to be marketed without a new drug application.
The concern with the active ingredients in chemical sunscreens, on the other hand, is that research has shown some of them can enter the blood stream after being absorbed into the skin.
It's important to note, however, that this doesn't necessarily mean that these chemicals are unsafe or cause harm.
The FDA instead says that additional data are needed for each of the 12 active ingredients used in chemical sunscreens to determine whether the absorption of any causes long-term effects.
"We don't know these chemicals are bad," says Christenson. "Continue to use them if that's what you like to use or they're convenient for you. Whether it's mineral-based or chemical, keeping sunscreen on all the time is the key."
Two previously used chemicals, aminobenzoic acid (PABA) and trolamine salicylate, are not safe — which is why the FDA no longer permits their use in non-prescription sunscreen products.
Christenson also points out that mineral sunscreens are also much friendlier on your skin, particularly your face.
"A mineral sunscreen is so much better for your skin," Christenson adds.
They're also safer for marine life, including fish and coral reef.
"From an environmental lens, I like to remind people that chemical sunscreens aren't reef-safe and are known to be harmful to many types of marine life," adds Christenson. "So if your trip is taking you to the beach, choosing mineral over chemical sunscreen can help protect the ocean."
Is mineral sunscreen better for sensitive skin?
For someone with sensitive skin or skin that's easily irritated, Christenson definitely recommends choosing mineral-based sunscreens over chemical ones.
"The heat that's generated as a chemical sunscreen deactivates UV rays can trigger irritation for people with sensitive skin," explains Christenson. "Mineral sunscreens simply reflect these rays, so they don't have this issue."
Plus, Christenson points out that zinc oxide is also a soother and healer of the skin, so it actually helps ease irritated skin, not trigger it.
The catch is that it's hard to find large bottles of mineral sunscreens.
"Certainly, use a mineral sunscreen on your face and other problem areas if you have sensitive skin," says Christenson.
This is where, then, filling in the larger areas of your body with a chemical sunscreen might make sense.