Daily skin cleansing, at any age is an important and essential procedure for our own care, since it not only removes dirt or any bacteria from the skin, but also the dead surface skin cells, preparing the skin to better absorb the topical treatments (drugs/creams).
Common problems such as irritation, xerosis, dermatitis, eczema, psoriasis, acne, rosacea, and photodamage, leave the skin vulnerable to external insults mainly due to an alteration of the stratum corneum (SC) skin barrier.
In the daily skin cleansing is therefore important to minimize any further weakening of the stratum corneum barrier, using mild and emollients cleansers, with neutral or acid pH (about pH 5.5) that do not attack or alter this barrier causing dryness, irritation and itching.
The structure of the skin acts as a barrier essential to maintain hydration of the skin within physiological values. The main factors of this barrier responsible for maintaining hydration are:
These components are subjected to a continuous renewal process determined by the ability of the epidermal keratinocytes to reproduce and differentiate continuously, thus giving rise to the various layers of the epidermis.
Different factors, both exogenous and endogenous, may affect these fragile defense mechanisms, causing lower or higher skin dehydration. The extent of skin hydration depends on the humidity, the hygroscopic properties of the stratum corneum and the presence of naturally moisturizing factors, without which you have dry skin. In addition to age and genetic predisposition to skin aging, many external factors can lead to lower or higher skin dehydration. The main factors of dehydration are chemical (eg, the solvent action and loss of skin lipids caused by the continuous use of surfactants) or due to unfavorable climatic or environmental conditions: wind, cold, and humidity, separately or in combination, cause dehydration of the stratum corneum leading to dry, rough, scaly and cracked skin, redness, itching and irritation. Even prolonged contact with water, despite the protection of the sebaceous-sweating film, causes a depletion in NMF. Indeed, a topical application of water alone causes a stress on all the stratum corneum that causes an alteration of its barrier function. The more exposed areas, such as face and hands, are the most affected; however also other areas of the skin are particularly prepared to excessive dryness often associated with a more or less evident flaking skin.
A dehydrated skin favors the entry of foreign substances, the onset of inflammation and causes loss of elasticity and tone. The application of topical cosmetic formulations on the dehydrated skin is able to restore smoothness, softness and distensibility. Therefore it is necessary to intervene with moisturizing treatments that prevent skin dehydration, and at the same time restoring the optimal content of water and other substances, which may be impaired as a result of multiple factors. Topical treatments are able to intervene on the hydration of the stratum corneum and also to convey compounds able to bring water, and to restructure the skin barrier which is essential to effectively replenish and restore the water and lipid content of the skin (collagen, hyaluronic acid, urea, ceramides, plants lipids and fatty acids treatments). The moisturizing efficacy of a formulation is due not only to the presence of specifically moisturizing ingredients, but also to the choice of vehicle and cosmetic form that contributes to the transfer of such property.