Why High pH Facial Soap Causes Varying Skin Reactions
Question
Why does facial soap with a high pH (around 9) cause skin irritation (peeling, stinging, itching) in some individuals but not in others?
Answer
Hello,
I understand you're wondering why a facial soap with a pH of 9 causes skin peeling, stinging, and itching in some people but not others.
The main reason is the soap's high pH compared to the natural pH of the skin.
- Natural Skin pH: Our skin has a natural protective layer called the "skin barrier" or "acid mantle," which has a slightly acidic pH of around 4.5-5.5. This layer helps protect the skin from bacteria, fungi, and pollutants, as well as maintaining skin hydration.
- Effect of High pH Soap: Using a soap with a high pH like 9, which is very alkaline, disrupts and damages the skin's acid mantle. This weakens the skin barrier, reduces its ability to retain moisture, and makes the skin more susceptible to external irritants.
- Individual Differences: Although high pH soap negatively affects the acid mantle in everyone, the severity of symptoms varies from person to person depending on several factors, such as:
- Baseline Skin Condition: People with dry skin, sensitive skin, or existing skin conditions like eczema or acne often have a weaker skin barrier already and are therefore more prone to irritation.
- Strength of the Skin Barrier: Some people may naturally have a stronger skin barrier, making them more tolerant to pH changes.
- Other Factors: Factors like the frequency of soap use, duration of contact, water temperature, climate, and other skincare products used in combination also affect skin condition and sensitivity to irritation.
Therefore, even with the same soap having a high pH, the reactions differ because each person's skin condition and the strength of their skin barrier are not the same. Some people have skin strong enough to tolerate it without obvious symptoms, while others with sensitive skin or an already weakened barrier will experience allergic reactions, irritation, stinging, itching, or peeling more easily.
Generally, using facial cleansing products with a pH close to that of the skin (slightly acidic pH) is gentler on the skin and helps maintain a healthy skin barrier.