FUNCTION & IMPORTANCE OF skin pH
FUNCTION & IMPORTANCE OF skin pH

Skin's pH plays an role in skin condition and pH plays an important role for proper skin function.


Many essential functions of the skin occur at a lower pH. 

Our skin is naturally between pH of 4-6.


Our skin is capable of buffering pH through production 

of fatty acids (sebum), natural moisturizing factors 

(epidermis) and other amino acids. 


The more acidic pH prevents bacteria overgrowth 

and allows optimal function of enzymes for making 

intercellular lipids like ceramides, and for proper desquamation. 


Elevated pH from aging, cleansing, 

and certain skin conditions such as acne and 

eczema leads to breakdown of skin barrier 

and further contributing to skin inflammation.


Schematic structure of epidermal barrier with its morphological and functional elements.

Acta Derm Venereol 2013; 93: 261–267 J Clin Med. 2011; 4(1):36-45
Acta Derm Venereol 2013; 93: 261–267 J Clin Med. 2011; 4(1):36-45


Skin pH  is key to skin's protective barrier

It neutralises alkaline-based aggressors (such as harsh surfactants), inhibits the growth of bacteria and restores and maintains the optimal acid environment in which skin's natural flora can thrive.


Skin pH can be divided into two parts: the outside and inside skin pH. 


The former applies to the skin surface and the latter to the pH-profile across the epidermis.

The inside and outside skin pH is addressed, as well as its importance and influence on skin barrier function.


The acidic pH is supposed to inhibit the growth of pathogenic microorganisms and keep the skin microflora in balance.


Key to restoring skin barrier is using gentle cleansers close to skin's natural pH, and moisturizers containing lower pH.


Internally: Age, genetics, gender, sweat, sebum, and anatomic location all contribute.

Externally: Cleansers and topicals used have the strongest influence. 


Skin pH is influenced by endogenous and exogenous factors

Skin pH – Healthy skin – Skin aging

The acidity of the outer surface of the skin is essential regarding the following functions: epidermal barrier homeostasis, integrity/cohesion of the SC (stratum corneum), support of proteolytic processes leading to desquamation, metabolism of extracellular lipids, and microbiological colonisation of the SC.

Our skin is host to more than many species of bacteria.Imbalances in the skin microbiome are associated with a number of skin conditions , irritation & dehydration

EMJ EUROPEAN MEDICAL JOURNAL, DERMATOLOGY • November 2014
EMJ EUROPEAN MEDICAL JOURNAL, DERMATOLOGY • November 2014

Skin surface pH  is controlled by endogenous and exogenous factors. Exogenous factors include skin microbiota, dressings, and skin care products. Gender, ethnicity, body site, sebum production, sweating, and age belong to the endogenous factors. All these factors have an impact on the acidification of the skin, which influences the permeability of the epidermis, the integrity/cohesion of the stratum corneum, and antimicrobial defence mechanisms. Modified from Schreml et al.