The Science of Zinc Oxide in Skin Care
Zinc Oxide in Skin Care
Zinc oxide is one of the most effective sunscreens in today’s skin care products. This naturally occurring mineral compound has numerous benefits for healthy, youthful skin.
In this detailed blog post, you’ll learn all about zinc oxide in skin care and how to incorporate it into your daily routine.
Take your free Baumann Skin Type Test today to find the personalized skin care routine that’s best for you!
What is zinc oxide?
Zinc oxide is made up of interconnected zinc and oxygen atoms. In its natural state, it is a fine, white powder.
While zinc itself is an essential trace element for the human body, zinc oxide has unique properties in skin care formulations.
Topically applied zinc oxide is usually deposited in the outermost layer of the skin, rather than penetrating deeper layers. This is key to understanding its mechanism and benefits.
In skin care, zinc oxide is primarily used as a physical broad-spectrum sunscreen.
It protects skin cells from UVA and UVB radiation by reflecting and scattering light waves, preventing them from damaging skin cells.
Before we get started, I want to introduce you to some of my favorite physical sunscreens:
The Science of Zinc Oxide in Skin Care
Zinc oxide is an important mineral for hundreds of bodily functions, and its properties are well-studied.
New studies are constantly being published on the potential benefits and drawbacks of zinc oxide in topical products.
We know that zinc oxide has other skin benefits besides sun protection, which we will discuss in detail below.
Sunscreen with Zinc Oxide
Zinc oxide is the most common ingredient in mineral sunscreens.
Due to its mineral composition and poor skin absorption, zinc oxide effectively blocks UVB rays (wavelength 290-320 nm) and short-wave UVA rays (320-340 nm).
This prevents sunburn, cell mutation, premature skin aging, and skin cancer.
Zinc oxide blocks long-wave UVA1 rays (340-400 nm) better than the mineral titanium dioxide. It provides very broad protection.
Research shows that it not only reflects radiation, but also absorbs a large portion of it.
Zinc Oxide for Melasma
Through UV protection, zinc oxide helps prevent melasma and post-inflammatory hyperpigmentation, especially for those who are prone to discoloration.
UV rays that trigger excess melanin production are blocked before they reach skin cells. Additionally, oral zinc supplements can treat existing melasma.
Good sun protection is key to treating hyperpigmentation.
Zinc Oxide and Blue Light
Zinc Oxide and Blue Light
Recent studies have shown that zinc oxide can protect the skin from visible blue light emitted by digital devices and fluorescent lights, which can cause premature aging of the skin over time.
While further research is needed, this mineral shows potential to neutralize blue light.
Antimicrobial Effects of Zinc Oxide
Most zinc oxide formulas do not penetrate the skin, but instead stay on the surface of the skin, providing antimicrobial benefits, where nanoparticle zinc oxide has shown antimicrobial properties in studies.
This means that zinc oxide cannot directly treat acne in most cases, and even in nanoparticle form, it is not enough to prevent acne on its own.
Is Zinc Oxide Safe?
Zinc oxide is considered a safe skin care material. Organizations such as EWG rate it 1-3, which is considered safe in most formulas.
CIR also describes it as safe. (10) It is not safe in all formulations because zinc oxide in nanoparticle form can be partially absorbed by the skin.
Zinc is different from some chemical sunscreen filters, which can cause irritation, allergies, or seep into the bloodstream in some people.
Zinc oxide, as a physical blocker that sits on the surface of the skin, is less susceptible to such reactions.
Be sure to wash off thick sunscreens at the end of the day to prevent them from clogging pores. Zinc oxide itself is not comedogenic, but some ingredients it is sometimes combined with can cause it.
Zinc Oxide Product Manufacturing
Zinc Oxide Product Manufacturing
To achieve the above benefits, zinc oxide must be properly formulated in skin care products. Factors such as shape, coating, and mixing with other ingredients can affect its effectiveness.
Here are some scientific findings on this claim:
Zinc Oxide Particle Size
Depending on the application, zinc oxide has different particle sizes, which can affect its properties and effectiveness:
Nano zinc oxide contains tiny particles less than 0.2 microns in size. This makes them appear transparent on the skin and does not leave a white tint.
However, there are concerns that nanoparticles may penetrate the skin.
Micronized zinc oxide particles are slightly larger, at 0.2–0.3 μm. This particle size minimizes light scattering and ensures clarity, but is still too large to penetrate deeply into the skin.
Micronized zinc oxide offers the best of both worlds.
Larger, non-micronized zinc oxide particles are approximately 0.5–1 μm in size. They tend to leave a thicker, white residue on the skin, but are sometimes used in natural or mineral makeup.
Solid zinc oxide particles are larger than 1 μm and appear noticeably white on the skin.
Although they provide effective UV protection, most consumers consider the white residue cosmetically unacceptable.
The smallest nanoparticles provide the most elegant results, while micronized zinc oxide is too large to be absorbed by the skin, offering a balance between effectiveness and safety.
The best size depends on your skin concerns. Ultimately, the best sunscreen for you is the one you use regularly.
Zinc Oxide Coatings
Zinc oxide particles are coated with various coatings to improve certain properties:
Silicone, dimethicone, and polymer coatings make zinc oxide smoother, more visually appealing, and more water-resistant while enhancing UV protection. They also minimize photoreactivity.
Lecithin, glycerin, and aluminum oxide provide moisture and reduce particle agglomeration.
Larger zinc oxide particles are coated more frequently than smaller zinc oxide particles.
Mixing Zinc Oxide with Other Ingredients
Mixing Zinc Oxide with Other Mineral Sunscreens
While zinc oxide can absorb and reflect a fairly wide range of radiation, it works best when mixed with other ingredients, such as chemical sunscreen ingredients or other minerals, such as titanium dioxide or iron oxide.
To make sure all the ingredients in your sunscreen are working together to improve your skin’s health, take this quiz (coming soon!) and find the best sunscreen for you!
One interesting ingredient that can be used with zinc oxide is diamonds!
Products like Pavise Dynamic Age Defense use the highly reflective surface of diamond powder to significantly increase the radiation protection of your sunscreen. I highly recommend this product.
For our full range of sunscreens and SPF products, click here!
Pavise uses Diamond Core Technology to combine zinc with diamonds to create a clear, vegan, and marine-safe sunscreen that provides sun protection and antioxidants.
Zinc Oxide vs. Titanium Oxide
Like zinc oxide, titanium dioxide acts as a physical UV filter on the skin. However, there are some differences. Here’s how the two mineral sunscreens compare:
Zinc oxide offers slightly better UVA protection, while titanium dioxide offers excellent UVB protection.
Titanium dioxide is more photoreactive, and zinc oxide is more stable.
Titanium dioxide has a higher risk of penetrating the skin.
Zinc oxide is safer and less irritating overall.
In addition to protecting against UV radiation, zinc oxide also protects against blue light and discoloration.
For best results, a combination of the two minerals is ideal. The versatility of zinc oxide makes it an essential ingredient in skincare products.
Fun Facts About Zinc Oxide
The effectiveness and safety of zinc oxide has been scientifically proven. Zinc oxide is more than just a sunscreen.
Look for zinc oxide in sunscreens, moisturizers, serums, and masks to reap its many benefits. Your skin will thank you!
As always, the best skin care includes products tailored to your individual Bowman skin type. We’d be happy to provide you with personalized recommendations for zinc oxide tailored to your needs.
Take a test today and start your journey to healthy skin!
