Xerosis

• Skin structure
• Sebum and coat of sebum
• Xerosis (dry skin) and Pruritus (itching)
• Asteatotic eczema
• Care of xerosis, asteatosis and asteatotic eczema

Skin is composed of three primary layers: the epidermis, which has contact with the outside; the dermis, which contains sebaceous glands ; and the hypodermis-subcutaneous tissue, which is the bottom layer of the skin.

The "epidermis" plays a role as the barrier against external stimulation such as UV, chemical substance andbacteria.

The "dermis" is a thick layer containing water and secures the skin's firmness and resilience. It consists of collagen, elastin, hyaluronic acid and chondroitin sulphate etc. It provides essential nourishment and helps to make a coat of sebum which protects the skin by secreting sweat and sebum. And it also contains the lymph vessels, blood vessels, nervus, sebaceous glands and root hair etc.

The "hypodermis-subcutaneous tissue" consists almost entirely of subcutaneous fat. It plays an important role as energy storage, a function of maintaining body temperature and a cushion from outside pressures.

Sebum is a lipid substance synthesized by sebaceous cells and its main component is the neutral lipid (triglyceride). When sebum is synthesized in large quantities and beyond the amount of accumulation in a cell, sebaceous cells burst and sebum is extruded into the ducts of the sebaceous gland. The sebum is secreted to the skin surface through the pores, making a coat of sebum covering the skin surface.

The coat of sebum provides moisture and smoothness to skin and hair by preventing them from the evaporation of moisture and it also acts to protect them from external stimulation. Fat contained in sebum is broken down by indigenous bacteria of the skin and fatty acid is produced. Thus the skin surface is kept mildly acid (pH4.2～6.4) which prevents the growth of disease-causing bacteria and the defensive function of skin is enhanced.

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The decrease of sebum secretion due to stress or aging leads to the failure of the formation of the sebum coat and can easily get external stimulation. When skin is damaged, the evaporation of skin moisture is stimulated, skin metabolism is distorted, moisturizing and excretory functions also become lower. This then leads to skin problems such as dry skin, tiny wrinkles and skin roughness.

Xerosis (dorsum of foot)

1. If the skin is strongly scrubbed, more sebum is removed than necessary. Moreover, the barrier of stratum corneum is damaged. Do not scrub more than necessary. To keep precious sebum, you should briefly try to wash your skin very gently, with a soft towel or your hands. It's better not to use a washcloth made with nylon or a pumice stone. In addition, try to avoid using too much soap and washing an area too long.
2. Rinse your skin thoroughly so that there is no remaining soap or shampoo.
3. It's better to use a solid soap, which has a weak degreasing power, not a body shampoo. Using a body shampoo, the used amount of surfactant at once is too much compared to a solid soap. In addition, too much sebum in the skin is removed, and it can not rinse properly.
4. You should take lukewarm baths under 40℃, due to the fact that not only does a warm body increase itching but hot water also strongly irritates the skin and decreases the moisturizing functions.
5. Try to avoid taking a long bath, to prevent the efflux of sebum.
6. People who have dry skin should devise a plan, such as bathing once every 2 days.

1. In the case of asteatosis and asteatotic eczema, even weak irritation induces an itchiness. Therefore it is important to avoid wearing irritating cloth materials such as wool or nylon and best to wear cotton cloth which is highly hygroscopic and soft.
2. To prevent remaining laundry detergent in washed clothes, they need to be rinsed properly.
3. Keep away from cold water, chemical detergent and chemical fiber such as nylon as much as you can.
4. Do not directly apply a plaster or tape etc on the affected area.

1. You should regularly eat a balanced and digestible diet.
2. Please refrain from taking any stimulants such as alcohol and spicy foods, because sometimes these foods can make the body warm and enhance itching.
3. Try to avoid diets such as hot temperature foods, strong tasting foods and using foods which include scum (bamboo shoots, eggplants, yam and aroids).

1. You should use prescribed medication following the dosage and administration.
2. The application agent should be applied thinly and lightly.
3. An ointment is more effective than a cream from the point of view of the supplement lipid components.