I wanted to know if the benefits of clay for the treatment of acne are scientifically proven. Clay has played an important role in human civilization for over 15000 years. While most people know about it as a building material, it’s also had an important medicinal role since prehistoric times. It’s been used both internally (à la the latest celebrity craze of eating clay) and externally, in the form of good old spa mud therapy. There are a lot of good reasons for this, that (unlike a lot of other health/beauty fads) actually stand up to some scientific scrutiny.
If you want to know exactly why clay has been proven effective in the treatment of acne, read on. If you want to get straight to our recommendations see Best Mud Masks for Treating Acne.
Differences Between Kaolin and Bentonite/Montmorillonite for Acne Treatment
Before we get into the evidence I should go over the differences in types of clay. It isn’t as simple as just “clay”. There are a ton of different clays with many different properties. As you would expect, these different types of clay have different healing properties depending on their mineral composition. The type of clay you choose can have a big impact on treating acne.
There’s some controversy about the usefulness of these names but for our purposes we don’t need to delve that deeply into the debate. Just remember that there are two main types of cosmetic clay: kaolin, and bentonite,/montmorillonite. Researchers have also identified that although many types of clay have healing properties (for example when ingested) not all clays have the same antibacterial properties.
A clay without antibacterial properties may not be useful for the treatment of acne and other skin disorders. The scientific literature supports a finding that the bentonite/montmorillonite clays make up most of the healing clays but kaolin clays also have proven benefits.
Bentonite/Montmorillonite | Antibacterial Powerhouse
Bentonite is made up of almost 80% montmorillonite green clay, so they’re essentially interchangeable. The antibacterial activity in montmorillonite clay is so strong, in fact, that french green clays have been used to treat flesh eating bacteria and are even used as a scaffold in tissue engineering.
Kaolin | Absorbs Oils & Toxins
Kaolin clay, also known as China clay or white clay, is not as common as bentonite in cosmetics, but is still quite prevalent. The high adsorption and absorption capacities, cation exchange capacity, as well as the extremely fine particle size of certain clays, e.g. smectites (expandable clay minerals) and kaolin group minerals are important reasons why these minerals are used to remove oils, secretions, toxins, and contaminants from the skin. By adsorbing and absorbing moisture and impurities from the skin, the clays also serve to cleanse and refresh the skin surface and to aid in the healing of topical blemishes, the major selling point for many cosmetics.
The Scientifically Proven Benefits of Clay for the Treatment of Acne
The acne fighting properties of certain clays are well documented in the scientific literature. These properties are based on both the antibiotic activity of these clays as well as the absorptive properties, which draw oils, toxins and bacteria out of the skin.