What are the benefits of zinc oxide?

Also known as Zinc Oxide or zinc white, zinc oxide originates from pure zinc ore. It can also be fully synthesised. The zinc oxide or ZnO combines a zinc atom with an oxygen atom. It is obtained by oxidising metallic zinc vapour at high temperatures. The chemical reaction is written as follows.

2 Zn(solid) + O2 (gaseous) → 2 ZnO(solid)

This results, on one hand, in hexagonal and colourless crystals, or on the other hand, in loose white powder, following the refraction of light in the small crystals.

ZnO can also be obtained by incinerating zinc hydroxide, zinc nitrate, or zinc carbonate, according to the following reaction.

Zn (OH)2 (solid) → ZnO(solid) + H2O(liquid)

Zinc oxide is used in the food industry, the glass industry, and in cosmetics. In skincare, it exists in two forms.

• The zinc oxide microparticles are typically incorporated into deodorants or make-up products (foundations, eyeshadows, powders...). They have the unique characteristic of remaining visible on the skin.

• The zinc oxide nanoparticles, being smaller and finer, do not leave a white veil on the skin. They are often found in sun creams. Zinc oxide acts as a shield on the skin's surface. Indeed, it is effective in blocking and deflecting UVA and UVB rays, thus protecting the skin from the harmful effects of the sun.

It should be noted, zinc oxide is also used as a colourant, you can find it on INCI lists under the name CI 77947.

Zinc oxide is present in certain treatments such as makeup, sun creams, and purifying lotions. Its benefits for the skin and hair are numerous.

• Hiding Imperfections

Zinc oxide exhibits covering properties. It allows for the concealment of minor imperfections such as spots. Thus, it serves as a covering base in foundations, loose powders, or eyeshadows.

Another benefit, zinc oxide mattifies the skin, that is, it prevents it from shining. Due to this action, this ingredient is included in the composition of night and day creams, cleansers, etc.

• Soothing irritated skin

Zinc oxide also possesses soothing virtues. It alleviates redness and protects delicate or weakened skin from inflammation. This metallic mineral also has the advantage of absorbing moisture. It reduces the risk of nappy rash in babies, making it one of the ingredients incorporated in talcum powders. Furthermore, it diminishes sensations of burning and itching.

• Purifying the skin and the scalp

Zinc oxide is beneficial for oily or acne-prone skin. Indeed, it helps to combat the proliferation of germs and bacteria. It purifies and sanitises the skin while regulating sebum production.

Furthermore, zinc oxide aids in combating oily hair and greasy dandruff that may occur.

• Protecting the skin from UV rays

Zinc oxide acts as a UV filter. It forms a protective film on the epidermis and is capable of blocking both UVB and UVA rays. This matte white pigment is responsible for the white film left by sunscreens when they are applied to the skin. Be aware, in some products, it may be of nanometric size. The health risks are as follows: psuspected percutaneous penetration, suspected reproductive toxicity, suspected genotoxicity, suspected carcinogenicity. Furthermore, regarding the environment, there is also suspected aquatic ecotoxicity. Despite this, this UV filter remains bio-compatible according to the COSMOS standard.

At Typology, we apply the precautionary principle and exclude nanoparticles from our formulas. Our sun cream for the face with SPF50 and aloe vera contains non-nanometric zinc oxide.

• Neutralising unpleasant odours

Zinc oxide has the ability to absorb the acidic secretions produced by the sweat glands. It also neutralises the bacteria present in sweat, which are responsible for unpleasant odours when they come into contact with the skin. This active ingredient aids in eliminating foot and underarm odours.

• KERI J. E. & al. The role of zinc in the treatment of acne: A review of the literature. Dermatologic Therapy (2017).

• ABENDROT & al. Zinc-containing compounds for personal care applications. International Journal of Cosmetic Science (2018).