Is zinc oxide in cosmetics safe?

How to choose safe sunscreen and UV products

"It can cause spots and wrinkles"
"I don't like my skin burning."

For these reasons, many people apply sunscreen every day. Or, more likely, many people apply it every season when the sun is strong.

In another article, I wrote about the various risks associated with the UV absorbers used in sunscreens.

Why you should choose a sunscreen that is free of UV absorbers (Part 1)
Why you should choose a sunscreen that is free of UV absorbers (Part 2)

Taking such risks into consideration, we recommend that all those who contact CONCIO Academy use "non-chemical" sunscreens and makeup bases that do not contain UV absorbers.

Non-chemical products contain titanium oxide and zinc oxide as UV protection agents. However, even these ingredients carry risks that make them completely safe.

So today I would like to explain more about zinc oxide.

What is zinc oxide?

Zinc oxide is made by removing impurities from zinc ore, which exists in nature. It is a white powdery substance and is used in many cosmetics for the following purposes:

UV scattering agent

It forms a skin-like film that reflects ultraviolet rays (UVA and UVB) without being absorbed by the skin, preventing skin damage caused by ultraviolet rays.

Astringent

It shrinks the skin and pores, absorbing excess sebum and preventing makeup from crumbling and smudging caused by sebum.

Anti-inflammatory agents

Protects the skin and relieves inflammation.

Zinc oxide safety

Zinc oxide has been used for a variety of purposes since ancient times (some say since ancient Egypt!). Because it also has anti-inflammatory properties, it is considered safe enough to be added to ointments for wounds, rashes, and sores on the skin.

However, with the recent development of nano-technology for cosmetic ingredients , nano-sized zinc oxide is increasingly being used in cosmetics. However, there is a worldwide debate as to whether nano-sized zinc oxide may pose new risks that were not previously known.

What size are nanoparticles?

It's hard to imagine how tiny nanoparticles are.
For example, a sheet of paper is about 100,000 nanometers thick, while the nano-sized zinc oxide used in cosmetics is between 1 and 100 nanometers.

The size of a human epidermal cell is approximately 0.05 millimeters (50,000 nanometers), so nano-sized zinc oxide is much smaller (1/50,000th of a human skin cell).

It was previously believed that zinc oxide could not be absorbed through the skin .

However, when processed into nano-sized substances that are too small to be seen with the naked eye, it cannot be said with certainty that they will not be absorbed through the skin in the same way as before. Furthermore, very little is known about what effects they may have on the human body when absorbed through the skin.

Additionally, the human lungs cannot filter out nano-sized materials.
For this reason, health risks have been pointed out when inhaled through the nose or mouth. Considering the risks of inhalation, it may be safer to avoid the following products that contain nano-sized zinc oxide.

• Spray type sunscreen
• Face Powder
• Make-up Keep Mist

What is the risk of allergies?

Zinc oxide is also said to have a low risk of skin irritation and allergies .
A 2017 study also showed that nano-sized zinc oxide does not irritate the skin, just like conventional zinc oxide, although some people may experience rare reactions such as rashes or redness.

Does zinc oxide cause acne?

I've seen people say that cosmetics containing zinc oxide can causeacne , but is this true?

In general, zinc oxide is considered non-comedogenic. In other words, it is an ingredient that does not easily clog pores . It also has antibacterial and anti-inflammatory properties, so it is unlikely that zinc oxide alone will cause acne.

However, as mentioned above, zinc oxide has the ability to absorb excess sebum. There is a possibility that zinc oxide that has absorbed sebum may adhere to the skin and clog pores.
Nano-processing has also improved the ability to absorb sebum. This may be why more and more people are finding that their skin is prone to acne or dryness.

In addition, in many cases, the nano-sized zinc oxide used in cosmetics is coated with oil to prevent the risk of percutaneous absorption. If the oil is a type that easily clogs pores or does not suit your skin, it may cause acne.

If you are unsure, ask the manufacturer what type of oil they use.