Sitting on the very surface of your skin is a thin, slightly acidic film. You cannot see it or feel it, but it is one of the most important parts of how healthy skin functions. This is the acid mantle.
It is made up of sebum, the natural oil your skin produces, combined with lactic acid and amino acids from sweat. Together they form a protective layer that sits at a pH of approximately 4.5 to 5.5, an acidity that is essential because most harmful bacteria cannot survive at that pH, making the acid mantle your skin's first line of defence against infection and inflammation. It also activates the enzymes your skin needs for cell turnover, and it maintains the conditions your microbiome depends on to stay balanced.
The problem is that most skincare products, particularly cleansers, sit at a much higher pH than the skin. Many popular foaming cleansers sit at pH 7 to 9, significantly more alkaline than the skin's natural surface. Using these products repeatedly raises the skin's pH, disrupts the acid mantle, and sets off a chain reaction downstream. Barrier permeability increases, moisture evaporates more easily, irritants get through, the microbiome shifts, and inflammation follows.
Common signs the acid mantle has been disrupted
- Skin that feels tight or stripped after washing
- Products that sting or cause redness, even ones that used to feel fine
- A persistent feeling of dryness or dehydration that moisturiser does not resolve
- Increased sensitivity, flushing, or unpredictable skin reactions
- Recurring breakouts, particularly if they are small and clustered
Restoring the acid mantle is one of the first things we work on. It is not complicated, but it requires removing what is disrupting it and giving the skin the conditions it needs to rebalance. In many cases, simplifying a routine is more effective than adding anything to it. It is also where our name comes from. Skin Mantle reflects our commitment to respecting the acid mantle, rather than working against it.