Skin Cleansers Aid Sensitive Skin

Skin cleansers may be an important adjunct to the regimen of those who use cosmetics, have sensitive or compromised skin, or utilize topical therapies. Cleansers emulsify dirt, oil and microorganisms on the skin surface so that they can be easily removed. During cleansing, there is a complex interaction between the cleanser, the moisture skin barrier, and skin pH. Cleansing, with water, soap or a liquid cleanser, will affect the moisture skin barrier. Soap will bring about the greatest changes to the barrier and increase skin pH. Liquid facial cleansers are gentler, effecting less disruption of the barrier, with minimal change to skin pH, and can provide people with a cleanser that is a combination of surfactant classes, moisturizers and acidic pH in order to minimize disruption to the skin barrier.

Skin cleansers are surface-active substances (i.e., emulsifiers/detergents/surfactants/soaps) that lower the surface tension on the skin and remove dirt, sebum, microorganisms and exfoliated corneum cells in an emulsified form. The ideal cleanser should do this without irritating, damaging or disrupting the skin and the moisture skin barrier. Water alone removes approximately 65% of oil and dirt from the skin, but is less effective at removing oils of cosmetic import and some environmental insults. Soaps are the oldest surfactants, and are chemically defined as the alkali salt of fatty acids with a pH of 9.5-10. Synthetic detergents vary in composition and surfactant types (i.e., anionic, amphoteric, cationic, non-ionic, and silicone) and pH. In modern usage, the term “soap” generally refers to any cleansing agent regardless of chemistry.1

Skin cleansers consist of the following:
• Water
• Surfactants (to emulsify the debris)
• Moisturizers (to hydrate the skin and maintain the skin barrier)
• Binders (to stabilize the formulation)
• Lather enhancers (found in some products)
• Fillers (generally used to harden bar soaps and cleansers)
• Preservatives (to prevent the growth of microorganisms)
• Fragrance (generally used to mask the odour of surfactants)
• Dyes or pigments (found in some products)

Skin cleansing may disrupt or disturb the moisture skin barrier, affect the skin surface pH, and irritate the skin. The moisture skin barrier protects against transepidermal water loss, chemical insult and xenobiotic penetration while preserving water to moisturize and maintain the smoothness and flexibility of the skin. A compromised barrier has been correlated with psoriasis, ichthyoses, and atopic dermatitis.2 Moisturizers, both emollients and humectants, within cleansers can maintain skin hydration as well as maintaining and restoring barrier function.3 Emollients impair evaporation of skin moisture by forming a film on the skin surface to impede water loss. Humectants attract and bind water, drawing it up from the dermis into the epidermis. The acid mantle of the skin plays an integral role in skin barrier function as well as regulating bacterial flora.4 Studies have shown that skin barrier regeneration/repair proceeds more slowly at neutral pH (7.2) than at physiological pH 5.5.5 Cleansers may also cause irritant or allergic contact dermatitis and this effect is enhanced if the skin barrier is compromised.

Conclusion

The choice of facial cleanser is important for people with normal skin, as well as for those people with sensitive skin and skin diseases such as atopic dermatitis, acne vulgaris. Liquid facial cleansers are the best choice for facial cleansing as they have an acidic pH, moisturizers and high rinsibility. Within the liquid cleanser category, the least irritating cleanser will contain non-ionic/silicone-based surfactants combined with moisturizers, as they will cause the least disruption to the moisture skin barrier and the normal skin flora.

B. L. Kuehl, PhD1 , K. S. Fyfe, H BBA2, N. H. Shear, MD, FRCPC3

1Scientific Insights Consulting Group, Mississauga, Ontario Canada
2GlaxoSmithKline, Consumer Healthcare, Oakville, Ontario Canada
3Departments of Medicine (Divisions of Dermatology and Clinical Pharmacology), and Pharmacology, University of Toronto Medical School; and Division of Dermatology, Sunnybrook & Women’s College Health Sciences Centre, Toronto, Ontario, Canada

Skin Cleansers - An Overview On Soap

Soaps, as we know them, were first used about 600 BC by the Phoenicians who combined goat fat, water, and potassium carbonate ash to form a solid soap. More recently, in 1878, Harley Procter developed a soap in collaboration with his cousin, James Gamble. They produced a soap by whipping air into a soap solution, this resulted in Ivory Soap, which is still used today.

Cleansing of the skin helps the skin to maintain a healthy, attractive looking, surface. It removes dust, perspiration, and some of the breakdown products of sebum. Makeup can also be removed. Foreign substances such as dirt will mix with the oil of the skin and become embedded. Water is inadequate to remove this. Soaps will be used to decrease the oil on the surface of the skin removing the dirt at the same time.

Soaps are essentially made of salts of fatty acids. The most commonly used fats come from animal and vegetable sources and include stearic acid, palmitic, oleic, as well as lauric. Soap particles will coat the fat droplets in which dirt is embedded and then will allow these to be removed by water.

Types Of Cleansers:

1. Bar soaps
2. Lipid free cleansers
3. Cleansing creams
4. Astringents and toners
5. Abrasive scrubs
6. Facial masks

Soaps can be irritating to the skin, the removal of the protective fat layer can lead to drying. A high pH of skin can also be irritating. Soaps can also combine with the calcium and magnesium found on the surface of the skin to form fatty acid salts which of themselves become irritating. The skin’s acidity may be affected. The acidity of the skin is important to inhibit bacterial and fungal infections.

1) Bar soaps:

Bar soaps are essentially salts of fatty acids, they are the most commonly used cleansers. They can be irritating, particularly to sensitive skin. A number of components can be added to soaps including the following:

* Moisturizers
* Fragrances & perfumes
* Preservatives
* Colouring agents
* Anti-bacterial compounds
Moisturizers:
Moisturizers will counteract the drying effect of soaps. The loss of the protective oil layer increases the chances of irritation. This can be counteracted by the use of moisturizing products such as glycerin, vegetable fats, or lanolin. The amount of moisturizer that is incorporated into soap is very small. Individuals who have a tendency to have dry skin should apply specific moisturizers after washing with soap rather than relying on the moisturizing component of soaps. Transparent soaps will have a high glycerin content and this tends to absorb water out of the skin, potentially causing more irritation.

Fragrances:
Fragrances are commonly used to conceal the odours of the raw ingredients of soaps. Some individuals will be sensitive and become allergic to these products. Anti-bacterial soaps will contain triclosan or triclocarban. A small residue will remain on the skin, which may inhibit bacteria. These can be useful in inhibiting unpleasant odours such as those found in areas where there are a significant number of apocrine sweat glands. These are found in the armpits and groin.

Mild soaps:
Mild soaps are designed to minimize irritations. They will not have colouring agents or perfumes. These do not tend to cause stinging of the skin or the eyes. Irritation or allergic reactions, while less likely to occur, may still be a problem for small children or for those who have very sensitive skin.

2) Lipid-free cleansers:

These are liquid cleansers that do not contain any fat. They will be applied to the skin and then wiped away or rinsed off with water. Many of these will contain glycerin, cetyl alcohol, sodium or sulphate, and sometimes propylene glycol. They will leave a very fine moisturizing film on the skin. These are particularly effective in removing cosmetics and are useful for individuals who have a tendency towards eczema. These may also be more helpful in older, drier skin.

3) Cleansing creams:

These creams can be used to both wash the skin and to moisturize it, they contain a mixture of mineral oil, petroleum, water, and some waxes. These are known also as cold creams, they are applied to the skin and washed off. They are useful for removing makeup and are usually made of heavy oils. These creams are helpful in removing sebum from the skin. They are gentler than other cleansers, and are recommended for dry skin, but are not that useful for those with oily skin or individuals with acne. Cleansing creams are best not used as moisturizers, as they are likely to cause irritation if left on for some time.

4) Astringents and toners:

These are perfumed or fragranced alcohol-based solutions designed to remove oil from the skin and will produce a tight feeling to the skin. Many multi-stat cleansing regimens will incorporate astringents that are used after a regular bar soap is used, they certainly have some benefit in removing alkaline soaps that tend to stick to the skin. Astringents are available for oily, normal, and dry skin. The high concentration of alcohol certainly removes sebum especially in those with oily skin for example, individuals with acne. They are the products used to control T zone oiliness.

5) Abrasive scrubbers:

These substances cause the rubbing off or exfoliation of the surface of the skin, they are available either as an abrasive sponge, or an abrasive scrub which has small granules within a cream base. These are used to remove skin scales, they work through mechanical means rather than through chemical action. They should be used infrequently, and cannot be tolerated on a daily basis, if used excessively they can cause damage of the stratum corneum, which is the surface of the epidermis producing redness and scaling.

6) Facial masks:

Facial masks are applied to the skin in a thick layer and are left on for 15-30 minutes, they are otherwise known as facials. It is said that these will produce skin tightening as well as deep cleaning of the hair follicles and pores. They may be used as a preventative treatment for acne. These products cleanse and moisturize the skin as well, they have a cleansing action through superficial peeling of the skin. They will leave the skin feeling moisturized, there is a general feeling of well being for some time after this is done, although it is not possible to fundamentally change the skin longterm with these products.

Some masks are applied and rinsed off with water, these are absorbent masks that are made of insoluble powders, clay, and mud, or gel masks that contain substances such as tragacanth. A mask that is peeled off will be vinyl or rubber based, and will harden, and form into a transparent sheet that will have to be removed. Facial masks that are used for acne will absorb oil from the skin, and some of them can be integrated with sulpha and benzoyl peroxide.

Excessive cleansing with a mask can certainly cause irritation and occasionally there may be a secondary infection. Once these masks are removed, moisturizer should be applied to the skin to minimize the superficial peeling that follows.