Skin pH, Acid Mantle and What They Mean for Your Skincare
To know your skin, you only need to learn a few things. You may remember that old grade-school joke; “YOUR EPIDERMIS IS SHOWING!” Well, it starts there. The epidermis is the outer layer of the skin, which together with the bottom-layer dermis forms the 4-5 layers that comprise your skin.
In matters of skincare, most products target the epidermis. This is where all the action takes place. Melanin (or skin pigment) is distributed in the epidermis. Pores are located in the epidermis. The very top layer of the epidermis is called the stratum corneum and it is also the location of your skin’s acid mantle.
MY ACID WHAT?
You may or may not have also heard the term “acid mantle” when referring to your skin. We all have an acid mantle. The acid mantel is a key part to our skin bio-chemistry. The acid mantle is a very fine slightly acidic, yet oily film on the surface of the skin that acts as a barrier to bacteria, viruses and other potential contaminants that might penetrate the skin. It is our body’s way of protecting us from disease and infection. Sweat and sebum form the acid mantle.
The pH of the skin is between 4.5 and 6.2, so it is acidic. Contaminants and other chemicals are primarily alkaline in nature (meaning they have a pH higher than 7) and the skin’s moderate acidity helps to neutralize their chemical effects.
pH and the Acid Mantle
The term pH stands for the “potential of Hydrogen”. It is a measure of the Hydrogen ion concentration of a substance. The Hydrogen ion concentration is more commonly referred to as the acidity or alkalinity level. The more acidity in the substance, the lower the pH, the less acidity, the higher the pH. There are differing values of pH in the body depending on what function is being performed. For example, the pH of the stomach is very acidic, around 1, because stomach acids help break down the foods we eat. Our saliva and blood, on the other hand, are much closer to neutral. Neutral substances, like water, have a pH of 7. A pH above 7 is considered alkaline (less acidic), and a pH below 7 is considered acidic.
For most people, the pH of the acid mantle is about 4.5 to 5.5.
If you strip the skin of its acidic mantle by using strong alkaline soaps or cleansers, bacteria will more easily attack the skin. Moreover removing the acid mantle disturbs the distribution of dead cells (the stratum corneum) on top of epidermis.
Many people use soap and water to clean their faces without realizing that this may not be beneficial. Soapy water is highly alkaline (with a pH of 12) while our skin is naturally acidic (with a pH of approximately 5). Soap or other detergents are commonly used as a cleanser because they remove the natural oils and the accumulated dirt from the skin.
While this leaves the skin with that “clean feeling,” soap is actually neutralizing the skin acid pH, thereby stripping away natural defense systems. If you suffer from acne or and wash your face multiple times a day, you are stripping away your acid mantle and can actually worsen your condition. Similarly it is important to know the pH of any cleansers, moisturizers, makeup and other products you use so that you don’t remove the protective oils and acid mantle from your skin.
The stratum corneum is the outermost layer of the epidermis, composed of large, flat, polyhedral, plate-like envelopes filled with keratin, which is made up of dead cells that have migrated up from the lower layers. Keratin is a protein that helps keep the skin hydrated by preventing water evaporation.
These cells can also absorb water, further aiding in hydration, and explaining why humans and other animals experience wrinkling of the skin on the fingers and toes (“pruning”) when immersed in water for prolonged periods. In addition, this layer is responsible for the “spring back” or stretchy properties of skin.
By totally stripping your natural acid mantle, the dead skin cell layer is disturbed or totally removed, allowing bacteria an easy passage through to the epidermis. In normal circumstances the stratum corneum protects the skin against damages. To that effect, if one never cleansed the skin at all, these dead cells would accumulate, producing skin eruptions and general dullness. If totally removed, the skin is left defenseless to an extent. The trick in proper skincare is to find the right balance between acid and alkaline maintenance of the skin.
Acids Are Beneficial
Remember, when it comes to skincare and taking good care of your skin, acids are beneficial. You don’t want too many, nor do you want to strip them away entirely. Always be sure to check the ingredient list of your favorite skincare products for elements that can strip away natural oils and moisture. Take precautions to replace anything lost from your natural acid mantel by using the proper moisturizer for your skin type.
~Rachelle Dupree
Vivoderm Marketing and Communications
Tags: acid mantle, epidermis, facial cleansing, moisturizing, skin fundamentals, skin layers, skin ph