Résumé : |
This article looks at how to achieve effective a detailed overview of the exact state of the skin.
Specific amounts of water and lipids on the skin surface determine the composition of the hydrolipidic film of the skin. The various functions of sebum and moisture on the skin surface to keep it supple, flexible and healthy have been investigated from the beginning in the cosmetic industry.
The slightly acidic pH-value of the hydrolipidic film is a major protective factor for the skin, buffering acids and alkaline products that get in contact, as well as providing an environment favourable to our natural microbiome, at the same time restricting the growth of pathogenic microbes.
The term ‘acid mantle’ describing this aspect was first used in 1928 by Heinrich Schade and Alfred Marcchioni.1 Today, due to further technical developments and continuous research in dermatology and skin physiology, biochemistry, immunology and genetics, we know that the acidic skin pH value is involved in many more functions.
The pH value of the skin is influenced by different endogenic factors such as genetic disposition, age, gender, health, melanin content and sebum secretion. It is easily impacted by external influences, especially cleansing and care products, temperature (sweat) and relative humidity (moisture). |