Reviews published in cosmeticsLearn more about how clay and clay minerals are used in cosmetics and what benefits they offer, from UV protection to antibacterial functionality.
“[Clays] Properties such as adsorption, cation exchange capacity, physical exfoliation, and swelling, among others, allow them to be used in several types of cosmetics/dermocosmetics, both as active ingredients and/or starting materials. ” they wrote.
Clay and clay minerals are natural, environmentally friendly, low cost, and abundant. It can also be used in various formulations such as gels, creams, pastes, and ointments. As a cosmetic ingredient, clay can affect stability and color. As an active ingredient, clay helps with functions such as anti-aging, UV protection, oil control, and cleansing.
Before clay and clay minerals were used in cosmetics, they were used in spas and medicine for geotherapy and skin therapy, helping to stimulate circulation, increase absorption, and moisturize the skin.
Clay and clay mineral compositions
The composition of clay plays a major role in its application in the cosmetic industry. Clay containing silicone helps with hydration, inflammation, and skin regeneration. Those containing aluminum can absorb melanin and disperse the pigment. Clays containing those listed above, along with calcium, titanium, iron, and potassium, were found to have antiseptic, antibacterial, and regenerative activities.
Most clay minerals contain a mixture of elements such as oxides, carbonates, kaolinites, chlorides, and layered silicates.
Like other products in the cosmetics industry, clay must be tested to prove it has zero or low toxicity. Due to its high absorption capacity, clay can accumulate heavy metals, microorganisms, etc. As an example, talc is used for a variety of purposes and can contain asbestos. Rigorous testing is essential to ensure the safety of clays and clay minerals.
Uses and properties of clay minerals
Clay minerals can be used as active ingredients, and their functions range from preservatives to UV filters. Borax and zinc stone have been shown to have antiseptic properties, the authors write.
Something like kaolinite protects the skin with its high adsorption capacity. Clay minerals with high refractive index can filter ultraviolet light. Examples include rutile and zincite. Some clay minerals are used in toothpastes as abrasives and polishes, or to reduce sensitivity. Mica is probably one of the most well-known clay minerals and is used in cosmetic products such as lipstick and eyeshadow.
Clay application and active ingredients
Clay has functional properties such as oil absorption, skin cleansing, and moisturizing, making it useful in products such as exfoliants, deodorants, and face masks. Certain clays act like detergents when wet, making them useful as emulsifiers and soaps.
Using clay as an active ingredient in a face mask helps transport metabolites and bacterial toxins away from the skin. Clay particles improve blood flow while purifying the skin, increasing the supply of oxygen and nutrients to the skin. One study found that a face mask containing clay and jojoba oil helped reduce acne lesions.
Smectite and kaolinite clays help reflect or reduce UV rays when incorporated into sunscreens. “This is likely related to its composition, as the UV protection ability of clay has been shown to depend on the concentration of iron oxide in its components. The more you have, the better your protection against UV rays,” the authors write. “Clays were also found to contain other physical protectants such as titanium dioxide, zinc oxide, and silicon oxide.”
Other clays such as smectite and illite have antibacterial properties. As a starting material, clay improves stability and helps to thicken or suspend and transport active substances.
Although this study details the benefits of these products, the authors note that most of the literature reviewed is theory-based.
sauce:
cosmetics
2024, 11(1), 7; https://doi.org/10.3390/cosmetics11010007
“Clay and clay mineral usage scenarios in cosmetics/dermocosmetics”
Author: Sarruf, FD, et al.
