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This work was written in 2005 with a bibliography dating from the years 1959-1987. The researches and studies done in Dermatology after 2010 can be found in the works presented at the International Conferences.

1. Morphology of the Skin

Skin morphology
Normal skin
First, we must talk about the skin and its appendages – hair, sebaceous glands, sweat glands, nails. Although we all want them to have a normal and pleasant appearance, not all of us take care of them to prevent them from getting sick. It is necessary to have minimal information and knowledge about the main skin diseases in order to provide the dermatologist with as many clues as possible about the acquired condition, and once a collaboration with him is established and the results will be seen immediately.
Being in permanent contact with the environment, the skin is exposed to degradation and aggression. Therefore, its health must be a daily concern for each of us. The skin should not be seen only as a body “cover” that protects us from wind, water, but it should be seen as a very important living organ that protects the body. We can say that it is our largest organ, having an area of approximately 2 square meters, a weight of about 3-4 kg, which represents about one-twelfth of the weight of the whole body.
The relief of the skin appears flat and smooth, except for certain regions where it is furrowed by numerous protrusions, depressions, some of which are permanent others transitory.
Depressions are those furrows called folds. The folds are structural and locomotion.
Prominences are of two types: transient and permanent. The transient ones are conditioned by various external and internal factors, produced reflexively through the contraction of certain muscles. The permanent ones are generally found at the level of the joints.
Another category of protrusions are formed by interpapillary ridges separated from each other by interpapillary grooves located at the level of the fingers, constituting the fingerprints.
Skin color varies by race from light white to dark black, with variations in shades and colors between the two extremes. Age and sex condition color changes, children and young women having a lighter color than adult men. In both sexes, in old age, the skin color is darker.
Under the epidermis there are pigment cells, melanocytes. They produce pigments called melanin, to protect us from the harmful effects of ultraviolet radiation. Melanin absorbs the light energy, becoming darker in color, which is the reason why the skin tans, if it is exposed to the sun. Later, the melanin migrates to the surface of the skin and comes off together with the dead cells – the tanned skin becomes pale with time. In those with darker skin, melanin is produced in larger quantities. This pigment is found in all layers of the epidermis of people in tropical areas, giving them a dark skin color. People with white skin have melanin only in the lower epidermal layers. A certain carotene pigment, together with melanin, leads to a yellow skin.
The thickness of the skin varies between 0.5 and 4 mm. It is relatively thin in the body regions little exposed to wear or pressure and thicker on the surfaces that are more stressed, for example on the soles. Children have thinner skin than adults, and adults have thicker skin than the elderly. Women’s skin is thinner than men’s.
The consistency of the skin is soft, fat, velvety, slightly moist, qualities conditioned by the amount of physiological secretions.
The elasticity of the skin is very high, it can stretch a lot without breaking. A strip of 2 cm supports a weight of 2 kg without breaking. The skin can stretch slowly, producing a burst of fibers in the dermis without an external wound but leaving stretch marks as traces.
The mobility of the skin varies by region and the fat that covers it.
Skin luster. The skin shines in the regions where the hatching of the relief is missing (lip, earlobe, around the nail, etc.)
Under the epidermis lies the dermis, thicker than the previous one. Its upper part is woven by a network of collagen and elastin, which are special proteins. They ensure the elasticity and flexibility of the skin. There are many blood vessels in the dermis. When we are warm, the capillaries dilate and fill with blood. If the surface of the skin is covered with more blood, the body loses a greater amount of heat, that is, it cools down. For this reason we blush in great heat. If we are cold, the blood capillaries in the dermis narrow, to lose less heat, and the skin becomes pale.
The blood flowing through these extremely thin blood vessels carries the nutrients under the two layers of the skin, and from there it will carry the products of catabolism. If the skin is traumatized, the blood coagulates in the place of the wound and closes the wound. The formed scar protects against pathogens and excessive blood loss.

2.Anatomy of the skin

Anatomy of the skin The skin is made up of EPIDERM, DERM, HYPODERM.
The epidermis is made up of five overlapping layers of cells, named from depth to surface: basal or germinal, spinous, granulosum, lucidum and cornus.
All the layers come from the germinal layer, whose cells, as they multiply, are pushed to the surface, constantly changing their shape and structure.
The outer corneous layer of the epidermis consists of 20-30 rows of dead cells. These cells are placed on top of each other, like tiles, that’s why the skin stretches easily during movement. Every day, thousands of cells are shed from the skin, but it does not wear out, because the dead cells are permanently replaced with new ones.
The dermis is made up of a loose connective tissue, made up of three main components: the fundamental substance, the connective fibers and the connective cells.
The fundamental substance has an amorphous structure and is made up of a mixture of mucopolysaccharides, proteins, mineral salts and water.
Connective fibers are of three types: collagen, elastic and reticular, arranged in the form of a network.
The connective cells located in the fundamental substance and in the meshes of the connective network are fixed cells and mobile cells originating from blood vessels
The connective tissue has the role of connection, support, nourishment, storage, regulation and defense against infections. Blood vessels, nerve formations, pilosebaceous follicles and sweat glands are also found in the dermis.
Hair follicles and sebaceous glands that open into follicles are also found in the dermis. The latter produce a dense, greasy substance – sebum, which permanently infiltrates the surface of the skin, as a lubricating substance for hair and skin. Without this ointment, the skin would dry and flake, it would not withstand daily demands for a long time. A horipilatory muscle is attached to each hair follicle. If we are cold or scared, these muscles contract, and the hairs and skin rise; the so-called goosebumps are formed.
The hypodermis is made up of fatty tissue (adipose tissue) in the form of lobules delimited by fibrous septa originating from the dermis. These fibers connect the dermis to the organs below, for example the muscles. This fat deposit is also an insulating layer that works as a thermal insulator. If necessary, the body can use this fat deposit as a source of energy. If someone eats too much, the excess fat is deposited under the skin. Under the adipose layer, there are muscles, lymph nodes, as well as the main nerves and blood vessels.

Skin renewal
As I mentioned before, under the epidermis, in the germinal layer, the cells are in continuous division. The newly formed cells are then loaded with a resistant protein, keratin, which causes the cells to become keratinized. As new cells are born underneath, the keratinized ones will be pushed outwards. The time required for a cell to reach from the basal layer to the stratum corneum and to be eliminated is estimated at 26-28 days. This being her life span. Dead cells come off the skin in the form of barely visible scales. A person loses approximately 18 kg of skin in this form during his lifetime.
Glands of the skin
The skin is endowed with glands whose secretion spills over the surface of the skin. These glands perform important functions.
Sebaceous glands:
A sebaceous gland is attached to each hair follicle, located more superficially than the sweat gland. Their product, called sebum, consists of a fatty secretion substance, which the cell collects from blood fats and which makes the hairs and epidermis impermeable.
Sebum is eliminated through the space between the hair and its sheath. It has the role of lubricating the hair and skin.
When the secretion of these glands is insufficient, the skin becomes dry, and when it is exaggerated, it gives rise to seborrhea.
The sebaceous glands are under the influence of the sex glands. The appearance of seborrhea coincides with the appearance of puberty.
Sweat glands;
Unlike the sebaceous glands, they are found all over the surface of the skin, deep in the dermis, formed by an agglomeration of twisted tubules (sweat ducts), having the indispensable role in regulating body temperature, being more numerous and more developed in certain regions. The secretion of the sweat glands is called sweat.
This is a slightly salty, clear liquid with a characteristic smell that varies from individual to individual. It is rich in mineral salts and volatile acids. In cases of illness, it may contain urea and sugar. The secretion of the sweat glands continuously pours on the surface of the skin, yet it is imperceptible. Sweat, while evaporating, cools our body. The sweat glands produce 600-800 ml of sweat per day. On very hot days, however, we can evaporate even 2 liters of sweat.
A human has a total of around 3 million sweat glands, the total weight reaching 100 grams. There are quite a few sweat glands on the face, underarm, palm, and sole. In the palm, for example, we find 350 sweat glands per square centimeter, while on the back of the palm only 200.
Sweating also helps us grasp objects with a smooth surface
Other leather structures:

Meissner corpuscles.
Different nerve endings are also found in the dermis: they will transmit to the brain the excitations that cause the sense of touch. The painful excitations are taken over by the nerve endings that branch into the epidermis. In the upper part of the dermis, there are tactile receptors, or the so-called Meissner corpuscles, which perceive light pressure.
Ruffini and Krause corpuscles.
A little deeper are the Ruffini corpuscles that perceive heat, respectively the Krause corpuscles, responsible for perceiving cold.
Vater Puccini corpuscles
Towards the lower edge of the dermis are the Vater-Puccini corpuscles, which have the role of perceiving strong pressures.
If these nerve endings send an information to the brain, under the effect of painful stimuli, pressure, or heat, it will act the corresponding muscles, for example to withdraw the hand from near a fire.
The piloerector muscles
They are special muscles, attached to each hair follicle. When the hair contracts, it straightens. Thus, more air enters, and the insulation improves (especially in animals with hair, feathers or fur.
Hair follicles.
They are long and narrow tubes, each containing a strand of hair. The hair grows, as new cells are added at the base, from the cells lining the follicle. Older cells die when keratin forms inside them.
Pain receptors are the endings of nerve fibers in the tissue of most internal organs and in the skin (in the epidermis and in the upper part of the dermis). They are the receptors that send impulses when any stimulation becomes excessive. This is how the feeling of pain is generated
Hair plexuses or hair root plexuses are special groups of nerve fiber endings. Each forms a network around a hair follicle and is a receptor, that is, it sends nerve impulses to the brain when the hair moves.
The appendages, as the appendages of the skin are also called, are visible on the outside of the body and the epidermis. They are of ectodermal origin, being represented by hair and nails.

  1. The hair
    The hair is presented as a tubular, flexible formation found in a space called the follicle. The hair, together with the follicle, is called the hair follicle. One or more sebaceous glands are attached to it.
    The hair consists of two parts, one that is in the skin, called the root, and another outside called the stem or simply the hair.
    The terminal part of the root is more swollen and has the shape of a bulb, being called the hair bulb or the follicular bulb.
    This bulb has a cavity at the base (follicular papilla) that contains blood vessels and nerves, which has the role of providing nourishment to the hair. Above the follicular papilla are the bulbous germ cells from which hair results through their multiplication.
    If we section a strand of hair longitudinally, we can observe three areas. In the center is the marrow, in the middle is the bark or cortex, and on the outside is the epidermis or cuticle (protective membrane from the outside.)
    The pith and bark contain pigments, and all areas begin to progressively keratinize as they move away from the bulb.

Keratin is a hard substance that ensures the shape and strength of the hair. From a chemical point of view, it consists of a substance rich in sulfur and nitrogen, resistant to acids, ferments and high temperatures. Hair keratin comes in two forms: 1-straight keratin, a stable substance, and 2-curled keratin, which is unstable. Under the action of different physical factors such as moisture, heat or chemical-oxidizing substances, the two keratins can merge. This fusion is the basis of the curling of the hair.
Pigments give hair color. They are made up of melanins, complex protein substances, which generally have a black color, but also with variations from yellow, dark brown to black. Pigments are insoluble in water, but soluble in potassium hydroxide and concentrated acids. That’s why when we want to dye our hair, we must first bleach the hair with hydrogen peroxide, ammonia, or other substances.
Melanins are presented in diffuse and granular form. In hair there are both forms of melanin, and the color of the hair depends on the ratio between them.
Diffuse melanin gives the hair a yellowish color when it is slightly concentrated and reddish when it is very concentrated.
Granular melanin generates hair colors from brown to black.
Decolorizers act on granular melanin, which it transforms into diffuse melanin. The red color of the hair is given by a special pigment that contains iron, called trichosiderin.
The speed of hair growth is approximately 0.3-0.5 mm per day, so that in a month it can grow by 1-1.5 cm and in a year by 15-20 cm.
Hair growth lasts between 3-4 years, with variations between 2-6 years. This growth with the replacement of the hair at 3-4 years is the explanation why in certain regions (Europe) we do not find hair longer than 1.5 m. In Asia, the daily growth speed and the growth period being much higher, we can meet people with hair even longer than 8 m.
It should be emphasized that from the death of the hair until it falls from the head, it takes an average of 3 months and normally around 40-50 hairs fall daily.
The resistance of the hair is high to physical and biological agents and variable to chemical ones. The strand of hair cannot be broken with a blow of a hammer. It is also resistant to traction. To break a strand of hair, a weight between 50 g and 100 g is required, and can reach up to 160 g. Hair resistance is lower in children and the elderly and higher in adults. The hair (minus the bulb) is also resistant to rotting. That is why we can find intact hairs in deceased people even after 10 years.
The hair is flexible and elastic. This property is amplified by humidity. It can even lengthen by 20-30% under the action of a traction and returns to its original shape after its cessation.
Under the action of heat, the elasticity disappears and the hair becomes brittle. That is why it is not recommended to use strong heat sources to dry the hair after washing it.
Thanks to the sebum, the hair shows absorbent properties of dust and microparticles.


Hair and scalp hygiene rules
As I mentioned previously, sebum (the natural fat of the hair and skin) favors the fixation of debris from the scalp (dandruff), which collects between the hair strands and is more difficult to remove. After the sweat evaporates, different salts, urea, fatty acids and volatile bases that generate unpleasant odors remain on the hair.
For this reason, hygiene aims to keep the hair and scalp clean and to ensure the vitality and beauty of the hairstyle.
Depending on the greasing, the hair can be normal, dry, or greasy.
Normal hair requires combing, daily massage and periodic washing.

    The nail is a horny blade that covers the dorsal surface of the extremity of the fingers and toes. They are placed on what is called the nail bed and perform the function of protecting the last phalanges.
    The nail is made up of the nail body, the part we can see and the root, the part included in the skin. The regenerating organ of the nail is represented by its matrix, which derives from the surface epidermis. Nail growth is a permanent process throughout life (0.5-1.2 mm per week.

The peculiarities of the skin in relation to age.
The skin of infants and children differs structurally from adult skin. The child’s skin is more supple, the layers of the epidermis are not fully developed, they are built from fewer rows of cells, so the thickness of the epidermis is smaller. The stratum corneum is discrete, keratinization is reduced, which results in a greater transparency of the skin.
The dermis is richly vascularized, which makes the skin color pink in children.
The soft skin of children is more permeable, so some medicines work better through the skin.
The skin of the newborn is covered by a fatty coating, which protects the skin from the macerations that the amniotic fluid can produce. The sweat glands begin to function only a few months after birth. The lack of sweat and the reduced amount of fat make the acid mantle, which normally offers protection against microbial infections, unable to fulfill its physiological role. Because of this, children’s skin is very receptive to microbial infections, which explains the frequency of microbial dermatoses in children. Children’s skin, on the other hand, cannot fulfill its role as an immunizer through a reduced reactivity, characteristic of this stage of development. Allergic reactions appear in children only after the third month.
Skin in the elderly.
After 40 years, the aging of the skin organ begins. Clinical signs of skin aging are more visible on exposed parts of the body, where U.V. radiation acts. solar. The skin becomes rough, atrophic, dry, by decreasing sebaceous secretion and sweating, simultaneously with decreasing water content, as well as decreasing its inhibition.
The dermis, like the hypodermis, atrophies, the most important changes being observed at the collagen level. The collagen fibers in essence thin out, change their biochemical content, decrease their hydration capacity, manifesting hypermineralization tendencies with Ca deposits.
The vascular network is greatly reduced, as is the vascular resistance. In general, the oxidative reactions of glycogen metabolism decrease and the activity of a whole series of enzymes decreases.
In conclusion, in the aging process, the metabolism of the skin is much lower and hence the possibility of the appearance of some dermatological conditions much more easily and the delayed response to certain treatments.

3. Physiology of the skin

Physiology of the skin
Physiology studies the life and function of organs. The skin, as the covering of the body and as a protective organ interposed between the external and internal environment, fulfills countless vital functions, closely dependent on the entire organism.
The skin, being endowed with a highly developed vascular and nervous system, is in a close relationship with the whole body, especially with the nervous system. The current methods of investigation do not allow the complete knowledge of the intimate processes that take place in the skin.
The metabolism of the skin represents the totality of the physico-chemical processes, the exchanges between the cells and sums up the basic vital functions of the skin and the physiological tasks that the skin must perform in relation to the external and internal environment.
The unfolding of metabolic processes of the skin requires an environment that contains the substances necessary for exchanges, physical-chemical energetic transformations. These substances are inorganic and organic.
Inorganic substances
APA is an element with special physico-chemical properties. In its physiological state, the skin contains a large amount of water, in which organic and inorganic substances are dispersed in colloidal solutions. The water we drink is fixed after ingestion by the liver, where it is ionized so that it can pass into the blood. Through circulation, it reaches the capillaries, where it tends to enter into balance with tissue water. For this purpose, the excess water is deposited in the muscles and skin, which constitute one of the most important water reservoirs in the body. From both places, water is mobilized as needed. Normally, the retention and elimination of water from the body must be proportional to the amount of water ingested. In numerous dermatological conditions, a water retention is produced, conditioned by a chlorinated retention, constituting the condition of preedema or edema.
Water, apart from its main role as a vehicle for inorganic and organic substances, also plays an essential role in cellular respiration.
Mineral salts
The amount of mineral substances is determined by the integral analysis of the skin ash. The skin contains approximately 45 mg of calcium, 260 mg of potassium, 350 mg of sodium, 30 mg of magnesium per 100 g, then chlorine, phosphorus, iron, sulfur, copper, zinc. Mineral substances are found in the body in the state of electrolytes charged with a certain electrical charge.
Sodium chloride, reaching the blood, dissociates into chlorine and sodium ions. The skin is the organ richest in chlorine, being the reservoir and regulator of chlorine in the body. The balance of water is closely related to that of chlorine.
Potassium is the ion of protoplasm and nuclei. In the skin, potassium is found more in the epidermis and appendages.
Calcium, phosphorus and magnesium are three elements so closely functionally related to each other that their metabolism cannot be treated separately. The large reserve of calcium and phosphorus is formed by the bones; in the tissues, calcium is found in a small amount, barely 1%. The blood contains a constant amount of 100mg of calcium per thousand, it being contained in the plasma. In normal skin, calcium is found almost exclusively in the dermis. The intermediate metabolism of calcium is related to that of phosphorus. Any mobilization, elimination and deposition of calcium is parallel to that of phosphorus, any excess blood phosphorus, to be eliminated, is fixed by calcium.
Calcium plays a role in neuro-muscular and nervous excitability, in the coagulation mechanism, in the impermeability of epithelial and endothelial membranes, it slows down and moderates cell activity. We can categorize it as a potassium antagonist. The K/Ca ratio is increased in skin inflammations.
Sulfur is found in large quantities in albumins and keratin.
For the life of the cell, it is of the utmost importance that the mixture of the mineral fraction be maintained in a constant balance.
An excess of potassium, calcium and sodium leads to a high pH. At the same time, excess sodium leads to water retention to correct hyperosmosis. Blood potassium increases in anaphylactic shock.

Through the participation of the sweat glands in the elimination of electrolytes from the extracellular environment, the skin plays an important role in the regulation of hydro-mineral metabolism.
Research on the skin has shown that normal skin has an acidic reaction, the skin of eczematous patients tends towards alkalosis, while the skin of psoriatic patients tends towards acidosis. Thus it can be said that when the imbalance is corrected, the dermatosis is cured.
The epidermis is more acidic than the dermis. The acidity is very marked at the level of the stratum corneum, where it can reach a pH of 5.5. The reaction of sweaty and fatty secretions can go down to a pH of 5. This acidic mantle of the skin plays a protective role against bacteria and parasites.
Organic substances
The metabolism of the skin is conditioned by the presence of organic substances that are supplied to the skin via the blood vessels. They serve the nutrition of the cells.
These organic substances are:
Proteins are made up of amino acids. They are divided into simple proteins and conjugated proteins. They are decomposed by boiling with mineral acids or by the action of natural ferments (pepsin, trypsin, etc.) In addition to common proteins (albumins, globulins), special proteins are also found in the skin. Collagen, known by its fibrillar structure, macerated in water turns into glue. Elastin is resistant to the influence of chemical substances. Reticulin is the protein of reticular fibers.
Carbohydrates are monosaccharides and polysaccharides. They are found abundantly in the epidermis in the first half of fetal life. They gradually disappear from the depth to the surface, to reappear in adults in the hair bulb, in the sweat and sebaceous glands.
fats, lipids come from the secretion of the sebaceous glands, from the evolution of the epidermal cell and to a small extent from the secretion of the sweat glands. Lipids are part of the composition of living matter. They do not dissolve in water, they have an energetic role and are also part of the plastic material of the cell. The reserve fat accumulated in the adipose tissue has a protective, mechanical and physical role (it dampens mechanical shocks and reduces heat loss)
Skin fermentations
The chemical reactions that are the basis of vital manifestations take place through the intervention of special agents, called ferments. Their action is similar to that of catalysts, hence the name biocatalysts, they cause cleavage and synthesis reactions, without wearing out. They act in extremely small quantities. These catalysts are called ferments, enzymes, diastases.
Vitamins and minerals
Vitamins are essential food factors for life. Their action is similar to that of enzymes and hormones, consisting in catalyzing chemical reactions in living matter and determining the chemical coordination of vital energy processes.
Vitamins are considered as biocatalysts, stimulating, like fermentation and hormones, energy-generating chemical reactions and especially oxidation reactions.
The lack of vitamins in the diet produces a series of metabolic disorders that manifest themselves through very varied symptoms, including the skin. However, the deficiency of a vitamin is only one link in the chain of multiple vitamin-mineral-protein deficiency conditions. This fact explains the failures of correcting deficiencies by administering only one vitamin, neglecting to correct the polynutrient nutrition regime.
Vitamins are divided into fat-soluble and water-soluble.
fat soluble vitamins:
Vitamin A plays an important role in the metabolism of proteins, lipids, carbohydrates and basal metabolism.

  • The recommended average dose is between 1.5 and 3 mg
    Some specialists specify that the necessary daily dose for men should be 3 mg, for women 2.4 mg, and for children, 1.8 mg.
    In the form of retinol, vit.A is found in: pork, beef, veal liver, fish lard, eggs, non-fat dairy products.
    Beta-carotene is found in colorful vegetables such as tomatoes, broccoli, carrot, watermelon, spinach, asparagus, corn, beetroot leaves, dandelion leaves, mango, apricots, citrus fruits, pumpkin.
    Vitamin A deficiency is translated into the skin by processes of hyperkeratosis in ichthyosis, pityriasis, psoriasis, which is sometimes associated with the other symptoms of avitaminosis A. By administering vitamin A in massive doses, favorable results are obtained in these conditions.
    Vitamin D plays an important role in the metabolism of calcium and phosphorus, favoring their resorption in the intestine and their deposition in the bones.
    *The recommended average daily dose is between 10-20 mg
    Unlike the others, vit.D can be produced by the body.
    Ultraviolet rays trigger the synthesis process of vit.D in the epidermis.
    Vit. D is contained in fatty fish, sardines, salmon, herring, fish oil, egg yolk, butter, milk, non-fat dairy products.
    Vegetables do not contain this vitamin.


Vitamin D2 has a favorable action in the treatment of skin tuberculosis.

Vitamin E is the growth vitamin. It plays a role in the metabolism of collagen tissue, having an antisclerogenic action.
*The daily dose is between 12-20mg.
The recommended amount may vary depending on the geographical areas. In France it is 12-15mg, in Canada it is 3-10mg, in the USA 40-80mg, and here it is 12-20mg.
The main food sources rich in Vit.E are vegetable oils rich in unsaturated fatty acids: soy, sunflower, corn, oleaginous fruits: sunflower seeds, peanuts, cereal germs, green vegetables and tomatoes.
The administration of vitamin E is recommended in atrophic skin conditions and in collagen diseases, such as scleroderma, where it gives favorable results.

Vitamin F plays an important role in lipid metabolism.
In various diseases with metabolic disorders of the epidermis, local administration can lead to healing in children’s eczema. It can also be a valuable adjuvant in psoriasis.

Vitamin K, antihemorrhagic, plays an important role in the synthesis of prothrombin.
*The daily dose is between 10-55 mcg.
In general, children need an amount of 10-30mcg, and adults between 35-80mcg.
It is found in green vegetables such as broccoli, spinach, cabbage, peas, cauliflower.
Vit.K is also produced by our own intestinal flora.
In liver diseases, caused by digestive disorders and disorders in fat resorption, the synthesis of vitamin K is suppressed, which can lead to skin hemorrhages.

Water soluble vitamins.

Vitamin B1 is necessary for the degradation and use of carbohydrates. It has a role in water metabolism.
*The daily dose is between 1.2-1.5 mg.
In general, a quantity of 0.5-1.2 mg is required for children, for teenagers and women, a quantity of 1.3 mg, and for men, a quantity of 1.5 mg. People who consume more alcohol or coffee should take an increased dose.
Vit. B1 is found naturally in many foods such as brewer’s yeast, pork, fish, vegetables, milk, egg yolk. Floury pasta, bread and in general wholemeal flour also contain this vitamin.
Its administration in edemas from beriberi and in edemas associated with nutritional disorders of the child, led to favorable results.

Vitamin B2. plays an important role in cellular respiration. It also has an anti-infective role
*The daily dose is between 1.5-1.8 mg.
An amount of 0.6-1.4 mg is recommended for children, 1.5 mg for adolescents and women and 1.8 mg for men and pregnant women.
People who carry out their activity in a stressful environment, must increase the dose of vit. B2.
It is found in animal and vegetable products. Thus, we can find it primarily in the liver, in beef or pork, fish, eggs, integrated cereals and milk. Green vegetables, such as spinach, asparagus, broccoli, lettuce, are also an important source of beef. B2.
The lack of vitamin B2 can lead to the condition called zabaluta, which consists of a red scaling of the lips.

Vitamin PP has an important role in the metabolism of amino acids.
*The daily dose is between 13-20 mg.
For children, a dose between 7-15mg, 15-18mg for adults and 20mg for pregnant or breastfeeding women is recommended.
Vitamin PP can be found in white meat, fish, liver, veal and cow meat, cereals and wholemeal bread. Fruits are also an important source of vitamin PP – peaches, figs, dates, almonds, avocados, peanuts.
PP vitamin deficiency produces a series of manifestations such as: spring erythema, sensitization of the skin to sunlight.
In pellagra, skin erythema, in addition to nervous and gastrointestinal symptoms, is influenced by the administration of vitamin PP.


Vitamin H, anti-seborrheic, has a role in the metabolism of amino acids and in the metabolism of internal secretion glands and general metabolism.
The daily dose is 0.3 mg (300 mcg)
However, children need an amount of 50-90 mcg/day
*Sources: Raw vegetables and fruits, fresh meat, beef organs, brewer’s yeast, milk, dairy products. egg yolk, can be sources to ensure the daily needs of cattle. B8
The lack of this vitamin can be signaled by the graying of the hair or even its whitening.

Vitamin B5-Pantothenic acid has a role in the metabolism of proteins, lipids, in the growth and maintenance of hair color.
*The daily dose is between 10-15 mg.
Children should consume between 3-8mg, adolescents and adults between 10-15mg.
The foods that contain this vitamin are: brewer’s yeast, beef organs, integrated cereals, peanuts, salmon, egg yolk, mushrooms and green vegetables.
The administration of this pantothenic acid can sometimes lead to the recoloring of the hair and the disappearance of seborrhea.

Vitamin C has oxidoreductant properties, intervening in the oxidation process and fulfilling an important role, especially in the function of supporting tissues. It intervenes in numerous metabolic processes, especially in pigmentogenesis and sulfur metabolism. In pigment metabolism, vitamin C has an inhibitory action and the oxidation influenced by ultraviolet radiation leads to skin pigmentation.
The daily dose is between 60-100mg
Children need 35-60mg/day, adults 60-100mg and expectant mothers 130mg. Smokers should pay special attention, because they should consume 120mg daily
The main sources of vitamin C are vegetables and fresh fruits, especially citrus fruits, raspberries, currants, strawberries. Among the vegetables: broccoli, potatoes, peppers, tomatoes, cabbage, parsley contain a sufficient amount for the human body.
Vitamin P has a role in cellular, ionic, protein, carbohydrate and water metabolism.
Vitamin P is successfully administered in gingival hemorrhages, gastrorrhages, eczema, erythema nodosum.

4. Metabolism and functions of the skin

Metabolism and functions of the skin. Living matter is characterized by a continuous process of wear and tear of the proteins of the protoplasm. This process represents metabolism with its side of anabolism and catabolism (assimilation and disassimilation).

The protein macromolecule is formed by the chaining of a large number of amino acids and by polymerization.

In living matter, metabolism is characterized by two fundamental processes: synthesis and degradation. Any imbalance that occurs between them will lead to metabolic disorders that will be manifested by different skin changes.

The normal unfolding of the skin metabolism provides the skin with a series of functions that are intended to protect the body against toxins that, in contact with the external environment, can affect the integrity of the skin.

These functions, in conclusion, are defense functions.

  1. Function of the Epidermis

The function of the epidermis is concretized in keratinization and in the production of a fatty substance, corneous fat, which inhibits the stratum corneum.

Keratinization results from the metabolic processes that occur physiologically in the epidermal cells with the aim of forming a compact and resistant coating in the stratum corneum against various actions from the external environment.

Horny fat contains a lot of cholesterol, unsaturated fatty acids forming a true light brown fat.

  1. Function of the Dermis

Unlike that of the epidermis, whose activity tends in particular to the formation of the horny layer soaked in fat, the function of the dermis is more varied and complex.

The dermis is a large laboratory that intervenes in the nutrition of the skin. Blood circulation takes place in the dermis, the purpose of which is to ensure the intake of nutrients, on the one hand, and the transport of waste from the breakdown of nutrients to the organs of elimination, on the other hand, except for some substances, which can be eliminated directly on skin surface.

Circulation in the skin is ensured by blood and lymphatic vessels.

The latest physiological research has shown that in the skin, in addition to the blood circulation, there is an intra- and extracellular circulation.

  1. Pigment and melanogenesis

In the skin and its adjacent formations there is pigment, the amount of which is conditioned by race, environmental influence and certain physiological states. In general, the regions of the skin that are exposed to the action of the sun’s rays are more pigmented than those that are covered.

The pigment found in the skin is made up of melanin.

It must be emphasized that chemical substances (copper, iron, zinc, magnesium), radiation and food factors play a significant role in pigmentogenesis and that this biological phenomenon is subject to various physico-chemical stimuli, which all compete for pigment formation.

4.Skin changes


The horny layer, impregnated with fat, causes the skin to have a reduced permeability, which varies in relation to different physiological or pathological states.

The skin is permeable to fats, especially the more fluid they are. Oils have the greatest penetrating power. If penetration is done through a simple and slow application, it lasts 2-5 hours. If friction is applied, it may take 5-10 minutes. The power of penetration is favored by the viscosity of the fat.

Resorption of drugs incorporated in fats is possible.

The skin is also permeable to gases, but to a lesser extent.

The skin is permeable to volatile substances such as turpentine, ether, chloroform, iodine, alcohol, etc.


The skin is a good conductor of heat and electricity. Humidity, vascular congestion, thinning of the stratum corneum increase this conductivity. The skin is soaked in a solution of electrolytes, which are found in variable concentrations. It is the seat of electrokinetic processes and electric currents, characterized by a potential of electric resistance in a continuous change, in relation to blood irrigation and also to atmospheric electricity. The role of the skin is to balance the electrostatic potential differences between the electrical charge of the environment and the internal environment

5.The role of the skin

The role of the skin

  1. The role of protection and defense

The skin as a covering of the body performs a protective function against harmful influences that touch the skin from the outside.

The skin is exposed to various harmful factors from the external environment, of a mechanical, chemical, physical and microbial nature, as well as factors that act from inside the body.

Through its mobility on the underlying tissues, through the layer of fat and through its elasticity, the skin can absorb mechanical shocks. On the regions that are exposed to mechanical actions, the stratum corneum is thicker and more compact (palm), the dermis is more elastic and flexible, and the hypodermis covers them with a more abundant layer of fat.

The horny layer soaked with fat annihilates the hand to some degree the action of chemical and physical agents.

The epidermis, through its ability to reflect light rays through the pigment stored in the germinal layer, constitutes a protective screen that prevents light rays from penetrating deeply.

The layer of fat that covers the entire surface of the epidermis and the residual acids left after the evaporation of sweat forms, together with the fats of the epidermis, that acid mantle that constitutes the most effective barrier against the penetration of microorganisms into the skin.

The surface of the skin, compared to the inside of the body, has an acidic reaction. It becomes increasingly alkaline towards the deep layers. The acid-base balance of the skin, established at a pH value of 5.5, can be changed by washing with alkaline soaps, the skin thus becoming receptive to the attacks of microorganisms. Moreover, the acid-base balance is acidic on all internal surfaces that can be attacked by microbes, such as the stomach and vagina mucosa.

The acid mantle, keratinization, regeneration of the epidermis through the continuous removal of the exfoliating layer constitute an effective protection for the skin against microorganisms.

Faced with internal harmful causes, the skin reacts through inflammatory processes.

Thermoregulation role

The role of the skin in thermoregulation is very important. It is moderate in terms of the fight against cold, but extremely important in the fight against heat.

The mechanism of putting sweat secretion and thermal regulation into action in general is nervous and is realized in two ways: a) by exciting the skin receptors, the influx reaches the thermoregulatory centers and b) by the direct action of the increased (low) temperature of the body on the centers.

The action of the cold produces a vasoconstrictor reflex, through which the erector muscle of the hair contracts, producing at the same time a vasoconstriction. The contraction of the muscle produces a contraction of the skin, its surface shrinks and at the same time sebum is eliminated, which reaches the surface of the skin. Both processes prevent a more significant loss of heat.

Under the action of heat, the surface of the skin stretches with the simultaneous dilatation of the vessels and with an intensive arterial influx. This vasodilatory action produces a greater radiation of heat and determines the secretory action of the sweat glands. Abundant sweat spills onto the surface of the skin, where, through evaporation, it cools the body.

While at a normal temperature approximately one liter of sweat is eliminated in 24 hours, in case of very high temperature one liter per hour can be eliminated. The action of the sweat glands can be considered as a safety valve against the action of too high heat. Sweat is continuously removed through insensitive perspiration, which aims to compensate for temperature differences in different skin regions. In skin diseases in which these processes are absent, such as ichthyosis, patients continuously feel cold.

  1. Role of secretion and excretion

The two glands (sebaceous and sweat glands) have a main role in the secretion and excretion process of the skin.

The sebaceous gland, under the influence of the nervous system, secretes sebum that spills onto the surface of the skin. Sebum gives the skin its characteristic suppleness, protects it and prevents the penetration of various liquid substances. In general, sebum secretion in humans reaches almost 2 grams daily. Elimination is richer in regions with more glands. Simultaneously with the sebum, a whole series of disaggregation substances and heterogeneous substances are eliminated (for example iodine in iodine acne).

The sweat gland secretes sweat, which has an acid reaction. Sweat contains 99% water and 1% solid substances, inorganic salts. The action of the gland is under the influence of the central nervous system. Certain conditions that lead to an increase in the water content of the tissues, heat and psychological factors produce a richer sweat secretion.

Through sweat, a whole series of heterogeneous substances, medicines and toxic substances are removed from the body. It serves to a small extent as a compensator of kidney activity. The favorable action of hot baths and sun baths, sweat cures in various diseases and drug intoxications is based on the elimination of toxic substances from the body through sweat.

4. Rol in sensibilitate 

in its external position, it is exposed to the action of harmful factors from the external doctor. It has a very large sensitive surface. The importance of the skin as a sense organ is not appreciated enough. It can replace, for example. for the blind, the process of knowledge through the tactile one, they come to perceive the shape of objects and their size in space. There are four types of skin sensitivity: hot, cold (thermal sensitivity), then tactile, with its subdivision, painful sensitivity.

Each of these sensitivities corresponds to a specific stimulus and different receptor organs.

Skin sensitivity is unevenly distributed on the surface of the skin. On one square centimeter of skin there are: 12-13 cold points, 1-2 hot points, 100-200 painful points and 25 pressure points. Of the tactile points, most are on the fingertips, the palm, and the tip of the tongue.

It is important to know that conditioned reflexes can be developed for all skin stimuli. A special characteristic is presented by the conditioned reflexes elaborated by thermal stimuli, against which an inhibition of such a high intensity is quickly elaborated that one can fall into a deep sleep. This observation explains the deep sleep in which those who are surprised by avalanches of snow and cold ice fall.

Itching is considered to be a mild pain. It is believed to be made up of the tactile sensation, plus the painful one. Itching can be a conditioned reflex that is formed to various chemical and physical stimuli, coming from the external and internal environment.

  1. The endocrine role and the influence of endocrine glands on the skin

In order to explain in some cases the cause of death, caused by severe burns, the theory was put forward that the germinal layer probably fulfills a secretory function in which it would secrete substances capable of neutralizing certain toxins. However, it has been shown that the skin does not have the typical structure of an internal secretion gland.

Clinically, it has been found that the skin is under the influence of hormones in the body, a fact that manifests itself in all its structural transformations occurring during different periods of life, when some glands start a more complex activity.

The important role of the pituitary gland in maintaining the physiological balance of the skin can be noted. Suppression of the anterior lobe of the pituitary in laboratory animals produced trophic disorders of the hair and nails, the epidermis becoming parakeratotic, and in the dermis there was an atrophy of the collagen tissue. The anterior lobe of the pituitary gland is involved in pigmentogenesis and skin coloring.

The role of the parathyroid on the integument could be highlighted less. The lack of its secretion would lead to hair loss. Hypersecretion of the parathyroid would produce an increase in skin calcium in scleroderma.

The effect of sex hormones on the skin is so marked, that it can be used as a test in the study of the functioning of gonadotropic hormones. Under the influence of sex hormones, the structure of the dermis and epidermis changes, the skin becomes pigmented, and the appendages develop more intensively.

The adrenal gland has an important role in the evolution and metabolism of the skin. Adrenal insufficiency (Addison’s disease) is manifested by hyperpigmentation of the skin, which regresses under the action of cortisone and ascorbic acid. It would seem that this gland also plays an important role in psoriasis.

Insufficiency of pancreatic secretion disturbs carbohydrate metabolism in some dermatological conditions, such as repeated furunculosis, which improves under the influence of insulin treatment.

Insufficiency of the thymus acts on the skin in psoriasis vulgaris.

Endocrine glands in general have an important role in the normal evolution of the skin and especially in the pathogenesis of many morbid manifestations of the skin.

Immunological role

It is known that the skin is closely related to the body’s defense reactions. Clinical observations show that the skin has a defensive function in infectious diseases. It is known that the introduction of the toxoid, intradermally, is more effective than subcutaneously, and the rabies vaccine, introduced into the dermis, produces a solid immunity than subcutaneously. These particularities demonstrate the active role of the skin in the development of immunobiological processes, a role favored in part by the development of the anti-invasion ferment by the skin, with the aim of annihilating the effects of the ferments that facilitate the invasion of the skin by pathogenic microorganisms.

It is known that the skin participates intensively in the allergy process, reactivity that is part of the great problem of immunity.

In this sense, I would emphasize the fact that in patients with psoriasis, who followed the treatment with Deniplant, as the psoriasis disease was cured, the defense reaction of the immune system increased.

The main role in the immunobiological processes of the skin is performed by the reticulo-histocytic cells through the influences exerted by the cerebral cortex through reflex.

6.Skin hygiene

Skin hygiene
Skin care boils down primarily to washing it with soap and water, i.e. cleaning it. Water is the most important skin cleanser. However, ordinary water may contain a number of substances that irritate the skin, therefore it must be soft (softened). The inconvenience caused by water containing a lot of salts can be remedied by adding sodium borate or sodium bicarbonate to the toilet water.

The soap used must be neutral, without coloring matter and without perfume. These substances can cause irritation and create a special reactivity of the skin. There is soft soap based on potassium and hard soap based on sodium. The latter is suitable for the toilet. Soft soaps can irritate the skin. The best ones are those based on vegetable oils, honey and glycerin.

The toilet of the body is done by bathing with soap and water. The bath will have a temperature of 35-37 degrees Celsius, it can be done in the evening or in the morning. The bath between 15-20 degrees is tonic. The warm bath between 25-35 degrees is sedative. The warm bath of 35-40 degrees increases the activity of the heart. After the bath, too energetic frictions should be avoided, as they can damage the stratum corneum.

Bathing twice a week is recommended. If it is done more frequently, it dries the skin, suppressing the defense against pathogens. Of course, it is about the hygiene of the body in general and not about the hands, feet, or the ano-genital regions, which must be washed daily. The bath that is prescribed for therapeutic purposes can be modified by adding starch (200-300g), sulfur and other substances, indicated according to the effects we want to achieve, or we can make baths with balneological plants.

The air and sun bath has a favorable influence on the skin and the body in general, stimulating all metabolic processes. Sunbathing, so beneficial, must be practiced in moderation, its exaggeration can become dangerous.

The purpose of clothing is to protect against the harmful influences of the external environment, helping to regulate and maintain body temperature in a favorable balance. The clothing will be permeable in order not to prevent the elimination of carbon dioxide and sweat, it must be heat conductive, a property that wool, cotton and silk have. This quality protects the skin from cold and heat. Underwear must not contain colored substances, which can cause dermatitis.

Face care varies according to the structural particularity of the skin. In one way, oily, seborrhoeic skin is taken care of, and in another way, dry skin.

The dry skin will be washed with soft and cold water, the soap will be replaced with an emulsion of flour and almonds. Washing with olive oil is recommended. These are completed in the summer by cleaning with a mixture of alcohol and ether. The morning toilet, after washing with cold water, is completed with a fat cream.

Oily skin will be washed with warm water and soap, especially in the evening. The toilet will be followed in the evening by anointing with glycerin, and in the morning by applying a dry stearin and glycerin cream.

Creams, blushes, powders preserve the skin of the face and are a protection against harmful external agents (wind, sun, dust), provided they do not contain substances that can irritate the skin.

The hair will be combed in the morning and in the evening, thereby airing it and getting rid of dust, dander and other substances that can accumulate during the day. Combs and brushes should not be used by several people, especially children, who can be infected more easily. Men’s hair is washed once or twice a week, depending on whether the hair is oily or dry, and women twice a month. Washing is done with soap and water.

The use of spirit lotions is done with care. They dry the skin and predispose to various infections. Creams are used on dry hair. Hair washing can also be done with different shampoos.

Hands must be washed in the morning, in the evening, before meals and whenever they get dirty. Too frequent washing with soft soaps dissolves the horny layer and causes eczema in some people. After washing hands, a greasy cream is recommended for people with dry skin.

Nails will be cut short and round. Cutting the skin around the nail will be done with clean tools to avoid frequent infections, especially those produced by manicure.

The beard should be shaved daily. If the shaving soap is irritating, it can be replaced with a shaving cream.

Superfluous bristles will be removed by epilation or depilatories. Insufficient care can give rise to infections such as pyodemites, intertrigo.

Wash your feet daily with soap and water. In hyperhidrosis, special treatments will be applied.

In children, skin care is of great importance, because their skin is more fragile and more exposed to the harmful action of external factors. For the toilet of the skin, warm water and fatty, neutral soaps are the most suitable means. A greasy cream can be applied to children with dry face. Anogenital-inguinal toilet is important for fat children, because they are prone to intertrigo. It is recommended to powder the respective regions.

The hygiene of the genital organs is particularly important. Washing with warm water and soap fully meets the requirements of good hygiene.

7. Bibliography

Angelescu M, Pantea O.-Concepts and current therapeutic methods in dermato-venerology 1966

Bojor Ovidiu, Mircea Alexan- Medicinal plants – source of health

Borundel C. – Manual of internal medicine for middle managers. Medical Education Bucharest 1974

Coltoiu Al, Despina Mateescu, Sanda Popescu-Dermato-Venerelogy

Coltoiu Al. – Dispositional dermatoses. Ed. medical Bucharest 1973

Coltoiu Al, Forsea D.-Considerations on topical therapy in psoriasis. Bacau 1981

Coltoiu Al. Giurcaneanu C.-Treatment of skin virosis. Sinaia 1982

Coltoiu Al. Mateescu D, Popescu S, Trifu P.- Considerations on PUVA photochemotherapy in some dermatoses

Conu A. – Dermatology – Venereology. Didactics Ed 1976

Conu A.-Correlations between skin conditions and internal pathology. Medical Ed 1982

Conu A. -Dermatovenerology. Ed. Didactics and pedagogy Bucharest 1976

Conu A, Coltoiu Al, Nicolescu Fl.-Atlas of dermatovenerology. Medical Ed. Bucharest 1980

Corinne Stockley- Illustrated Dictionary of Biology Ed. Aquila’93 Oradea

Costea Gh. – Therapeutic and clinical guide of dermatovenerology. Ed. Facla Timisoara 1981

Chirila P. – Naturopathic medicine.Ed. Bucharest Medical School 1987

Degos R – Dermatology. ed. Fla,,arion-Medicine-Science Paris 1979

Dimitriu R, Roxin T.-Treatment of skin diseases. Ed medicala Buc 1970

Gh. Nicolau-Dermatology and Venereology.Ed. Bucharest Medical School 1959

Longhin S., Antonescu St., Popescu A.-Dermatology. Medical Ed. Bucharest 1971

Maude Bouchard -Vitamin therapy. Ed. Niculescu Bucharest

Miller D.A. et al. Chronic urticaria J. Med. 1968

Paun R.. -Medical therapy. Bucharest medical ed. 1982

Parvu C. Universul plantor Ed. Enciclopedica Bucuresti1997

Pinon C. Allergic pruritus. Med de france 1970

Popescu Gr.I, Paun R.-Allergic diseases. Medical Ed Bucharest 1967

Tirlea P et al- Congenital ichthyosiform erythroderma Valnet J. – Treatment of diseases with vegetables, fruits and cereals, Ed. Ceres Bucharest 1981

8. Photo gallery