Six Myths About Mineral Sunscreen and Why They’re Wrong
Mineral sunscreens containing titanium dioxide or zinc oxide are becoming a popular alternative to more traditional sunscreens. Unfortunately, there are many misconceptions about how mineral sunscreens work and whether they are better than chemical sunscreens. Let’s dispel some of these myths.
What is the difference between mineral, physical and chemical sunscreens?
Mineral or “physical” sunscreens are made from tiny particles of titanium dioxide or zinc oxide. Chemical sunscreens include almost everything else: oxybenzone, octisalate, and others.
The term “physical sunscreen” comes from the misconception (more on this in a minute) that these ingredients physically block the sun. Mineral sunscreens, as I will call them in this article, have a slightly whiter tint (unless they are tinted) and are more commonly found in sunscreens marketed for children or marketed as “baby sunscreens.” natural” alternative.
There are also sunscreens that combine both types of ingredients.
Myth: Mineral sunscreens are “sunscreens.”
Wow, no. Nothing in the bottle blocks the sun, which is why the FDA has banned the word “sunscreen” from sunscreen labels and advertising.
There is a myth circulating on the Internet that chemical formulations can only be sunscreens, while mineral formulations can only be sunscreens. This is not true and has never been true. Both are sunscreen.
You can use the term “sunscreen” if you want (since the FDA only regulates the company’s marketing, not regular speech), but it’s a synonym for sunscreen, not a completely different product. Sunscreen and tanning cream are the same thing, and they come in both mineral and chemical compositions.
Myth: Mineral sunscreens reflect UV rays, while chemical sunscreens absorb them.
This may seem pedantic, but this misconception leads to further misconceptions like the one above, suggesting that mineral ingredients “block” the sun.
In fact, both chemical and physical sunscreens work by absorbing ultraviolet light. Scientists used to think that titanium dioxide and zinc oxide reflected ultraviolet rays, but this is not true. Since 2015, we have known that mineral oxides primarily absorb UV radiation and only slightly reflect it .
Myth: Mineral sunscreen can be used in the sun immediately after application.
Mineral and chemical sunscreens are the same when it comes to the standard “wait 15 minutes after applying…” advice. In both cases, the sunscreen begins to work immediately. It does not need to be absorbed into the skin to be effective.
What’s really important is to make sure that the cream or spray is completely dry so that it has some resistance to rubbing against your clothes (or furniture, etc.). Drying also ensures that it won’t leak as soon as you step into the pool or start sweating.
Myth: Mineral sunscreen is a replacement for your old favorite chemical sunscreen.
This is partly true: you can get good protection from the sun’s rays with a mineral or chemical sunscreen. But chemical sunscreens are often easier to use if they provide the specified SPF.
This summer, my husband bought his favorite sunscreen for our vacation—a spray-on sunscreen from Trader Joe’s—but it was reformulated to use mineral ingredients rather than chemical ones. It worked completely differently.
Firstly, it turned white, opaque, and took a long time to rub in to keep us from looking pale and pasty. Some of us used it carelessly and probably got less protection; some of us went too far and looked like ghosts. It also took longer for the skin to dry, which was bad news for those of us who were itching to swim. I remember seeing my husband walk into the pool with his face covered in white sunscreen (“I don’t care,” he said about his appearance) and it running down his face as he swam.
He ended up with a sunburn on his face. The kids also developed sunburns on their shoulders, so I bought sun shirts for them and paid more attention to how we apply sunscreen to their faces. They were fine for the rest of the trip, but damn did I miss the old compound, chemicals and everything.
This doesn’t mean mineral sunscreens will always work poorly. But depending on the formulation, they may have some disadvantages compared to chemical sunscreens. For example, you may have to apply them in a thicker layer, but of course this will vary from brand to brand. Please note if you are changing products.
Myth: You can make your own mineral sunscreen.
It’s not easy to turn mineral ingredients like titanium dioxide into particles that are small enough to spread across the skin and still protect you. TikTok may try to convince you that you can make your own sunscreen from diaper cream and coconut oil, but that’s not true .
Myth: Mineral sunscreen is better for the environment.
Corals can (probably) be damaged by some types of sunscreens under the right conditions, but there is no clear dividing line that separates mineral sunscreens as good and chemical sunscreens as bad.
Oxybenzone, one of the chemicals found in laboratory tests to damage corals, has been banned in Hawaii. Some other sunscreen ingredients have also been found to be harmful. But that doesn’t mean mineral sunscreens are automatically safer. Research also shows that sunscreens with zinc oxide are harmful to corals . Meanwhile, it is unclear whether sunscreen actually reaches corals in significant enough quantities to affect them. “It is unclear whether [mineral sunscreens] are actually safer for corals,” states a Stanford article on sunscreen research.
The jury is still out on which sunscreen will benefit corals, but in her research review , chemist Michelle Wong provided a list of sunscreen ingredients considered less harmful to corals. These include titanium dioxide—a popular ingredient in mineral sunscreens— and several chemical sunscreen ingredients, including octocrylene, octisalate, and avobenzone.
When should you still use mineral sunscreens?
If you previously thought that mineral sunscreens were always better than chemical ones, I hope I’ve helped you see the nuances of those myths. But that doesn’t mean mineral sunscreens are bad or useless.
One benefit of mineral sunscreens is that they are less likely to cause allergies or irritation if you have sensitive skin. I use mineral sunscreen on my face even when I apply chemical sunscreen on my body because I have found that this mineral sunscreen will not irritate my eyes if I accidentally get it in my eyes.
The American Academy of Dermatology recommends mineral sunscreens for people with sensitive skin and children. Otherwise, they don’t prefer one formulation over another: “Any of these sunscreens can effectively protect you from the sun, as long as you choose one that is broad-spectrum, water-resistant, and has an SPF of 30 or higher.”