What are the benefits of zinc oxide?

zinc oxide or ZnO combines a zinc atom with an oxygen atom. It is obtained by oxidizing metallic zinc vapor, and this, at high temperatures. The chemical reaction is written as such.

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

This results in, on one hand, hexagonal and colorless crystals, or on the other hand, 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 makeup (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 sunscreens. 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.

Notably, zinc oxide is also used as a pigment, you can find it on INCI lists under the name CI 77947.

Zinc oxide is present in certain skincare products such as makeup, sunscreens, and purifying lotions. Its benefits for the skin and hair are numerous.

• Hiding Imperfections

Zinc oxide exhibits covering properties. It helps to conceal minor imperfections such as blemishes. 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 calms redness and protects delicate or weakened skin from inflammation. This metallic mineral also has the advantage of absorbing moisture. It reduces the risk of diaper rash in babies, making it one of the ingredients incorporated in talcum powders. Furthermore, it alleviates sensations of burning and itching.

• Purifying the skin and 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 sanitizes the skin while regulating sebum production.

Furthermore, zinc oxide helps combat oily hair and the greasy dandruff that can 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 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. Moreover, 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 sunscreen face SPF50 with aloe vera contains non-nanometric zinc oxide.

• Neutralizing unpleasant odors

Zinc oxide has the ability to absorb the acidic secretions produced by the sweat glands. It also neutralizes the bacteria present in sweat, which are responsible for bad odors when they come into contact with the skin. This active ingredient helps to eliminate foot and underarm odors.

• 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).