What is pH?

Let’s talk about pH and how it relates to your skin and skincare products. Classifying skincare products according to a standardised scale assists in understanding the impact various products within the skincare industry will have on your skin. There are three broad terms used in the scale, acid, base (alkaline) and neutral. The measure for this scale is called pH. pH stands for potential of hydrogen. The pH scale ranges from 0 – 14. Products that fall within 0 – 6 are considered acidic, products at 7,0 are neutral and products from 8 – 14 are considered alkaline.Simply put, the lower the pH the more potent the acid, while the higher the pH the more potent the alkaline. Put into practical application, blood has a pH of 7,4. Skin, the largest organ of the body has more than one pH.

The top dead layers of the skin, the Stratum Corneum have a pH of 5,5. The living layers of skin have a pH of 7,4. Most living cells within the body can live within a small band of pH which is around 7,0. This means that the living skin cells have a neutral pH while the outer layers are acidic.This acidic outer zone of the skin is referred to as the acid mantle. The outer layer of skin is acidic as this type of environment prevents bacterial overgrowth. Bacteria that live on skinstruggle to multiply in an acidic environment. Many enzymes that control normal skin exfoliation and lipid bi-layer production work best at an acidic pH. Therefore having an acidic mantlemeans skin has a normal, functional barrier. The outer layers of the skin become acidic in two ways; from components of perspiration and from the skin producing acidic proteins at the surface of the skin that assist in regulating pH.

Darker skin types have a more acidic outer barrier than lighter skin types and therefore have a better barrier than lighter skin types. People with dry skin tend to have a higher ph (less acidic) than people with normal skin. This type of skin has a less effective barrier and is therefore more prone to skin infection.
Understanding the potential impact that skincare products with different pH values can have on your skin’s acid mantle is important. For example, traditional soaps have an alkaline pH. Using a traditional soap as a face wash can disrupt your acid mantle leading to skin problems such as dryness, poor shedding, rough skin texture and irritation.