Zinc Oxide In Sunscreens: What Is It + 7 Facts Explained About The Active
Sun's out, zinc oxide out—that's how it goes, no? For a daily staple product, sunscreen really does have a lot of controversy surrounding it; this is largely due to how potentially harmful normal SPF ingredients are (to us and the environment). But here, we're looking at one of the safest and diving into its strengths, as well as drawbacks.
What is zinc oxide?
Zinc oxide is a mineral that's used as a physical sunscreen. Physical sunscreens shield you from the sun's rays by blocking UV; this is different from chemical sunscreens, which absorb the UV light and turn it into heat. It is found naturally as the mineral zincite and becomes the ingredient we use in our products through high-temperature oxidation. It is a popular ingredient for those in the natural space, and increasingly more of the general public, as more information comes to light about the dangers of traditional chemical sunscreens.
1. Protects against UVA and UVB.
Protecting against both UVA and UVB light is essential, as both wreak havoc on our skin and bodies leading to premature aging, collagen loss, and DNA degradation. However, not all SPF ingredients are good at targeting both. "Zinc oxide is a mineral that reflects light, including longer wavelength UVA, from the skin's surface. It is one of only two mineral—also referred to as 'nonchemical'—sunscreen active ingredients, but it is the only one that is effective at blocking UVA since titanium dioxide doesn't effectively block UVA," says board-certified dermatologist Loretta Ciraldo, M.D., FAAD.
2. It's arguably the safest option—for you and the ocean.
There's a lot of debate around sunscreens. We know from increasing amounts of research that many of the ingredients we've been using in standard SPF may have adverse health effects (or at the very least, we don't have enough research conducted to prove they are safe for use), as well as major issues for the environment like coral reef bleaching.
At the moment, zinc oxide and titanium dioxide are the only two ingredients the Environmental Working Group has deemed safe for use and effective at protecting the skin from UV damage. And since we know that zinc oxide also protects against UVA, while titanium dioxide doesn't, it's the more essential of the two ingredients. This is why it's recommended that you always ensure your sunscreen has zinc oxide in it. It's also eco-friendly and doesn't show to have any effects on marine life as long as it's non-nano particles (meaning, broken down into minuscule particulate matter).
3. It casts a strong white film.
Here's the major problem with zinc oxide: It does not rub in easily and often leaves a white film over skin. "It does make a white cast on the skin and it makes the SPF thick in consistency," says Ciraldo. This is especially a problem for those with darker skin tones.
Modern, newer formulations are getting better: Brands mix the ingredient with more emollient-like ingredients so they are easier to smooth over skin. Or brands will add a variety of tints, to function something like a foundation-SPF hybrid, to meet the needs of a diverse consumer. It may take some guess-and-test to find an elegant option that works for your skin and skin tone, but given it's really the only safe, effective option out there, it's worth the legwork.
4. Most zinc oxide is produced synthetically.
To clear up confusion around the natural-versus-synthetic debate, zinc oxide can be derived naturally, but to meet the demand, it's most often produced synthetically, making it what is often called a "safe synthetic." As Ciraldo tells us, "Although it occurs naturally as the mineral zincite, most zinc oxide is produced synthetically in the lab." This isn't a slight against it but a point of clarification.
5. It's great for calming inflamed or sensitive skin.
"Zinc oxide is arguably the most skin-calming of all the active sunscreen ingredients," says Ciraldo. For irritated skin, applying any sort of product is a gamble. Zinc oxide has been shown to have a soothing effect on the skin, so you don't need to be apprehensive if you have naturally sensitive skin.
6. It's the safest option for acne-prone skin.
Those with oily and acneic skin might look at sunscreen as their worst enemy. Many forms are highly comedogenic and irritating, a huge issue for skin that's already inflamed and prone to clogged pores. However, Ciraldo says that zinc oxide may actually be beneficial for acne-prone skin as it is an anti-inflammatory. In fact, research has shown that zinc oxide is an effective treatment for zits, and it's even an ingredient in many natural spot treatments.
Not to mention, if you have acne-prone skin, you might also regularly be using an exfoliator like an alpha-hydroxy acid (think glycolic and lactic acids). These can make you more photosensitive, increasing your need for a safe sunscreen. "The best sunscreen to use when you are using AHAs is zinc oxide sunscreen. Zinc oxide is the ideal sunscreen because it is a full-spectrum sunscreen that is the least likely to irritate the skin. When using an AHA, your skin will be more sensitive, and it is often a good choice to choose a sunscreen with the least amount of chemicals, reducing the risk of an allergic or irritant reaction," says board-certified dermatologist Jeremy Fenton, M.D., of Schweiger Dermatology Group in New York.
7. It pills easily.
Another sensorial issue that many find with zinc-oxide-based sunscreens is that it pills under easily, a problem if you are planning to wear makeup over it: "It is the ingredient most associated with pilling, which means it can form tiny white spheres on the surface of the skin," says Ciraldo. Not everyone has this issue, but it's certainly a common complaint. The best way to avoid this issue is to let the sunscreen truly settle onto the skin and fully dry before you apply your makeup over it.
Zinc oxide isn't a perfect ingredient, sure, but at the moment it's the most effective and safest option we have for protecting skin against damaging UVA and UVB rays. (It's also great for those with acne or sensitive skin.) It may take work to find an elegant option that works for you and your skin tone, but it's worth the look given how powerful this ingredient is.
Want your passion for wellness to change the world? Become A Functional Nutrition Coach! Enroll today to join our upcoming live office hours.