What is skin? What is the structure of the skin?

Skin is the outermost organ of human body, covering the surface of human body to protect human body from various external stimuli (mechanical, physical and chemical) and various microorganisms, and it is the first natural barrier of skin. Healthy skin is a mirror that reflects the internal health of the body. Correct skin care requires a deep understanding of the skin mechanism.

The skin consists of epidermis, dermis, subcutaneous tissue and skin appendages, which are connected with the underlying tissues.

Epidermis: Epithelial tissue, located in the outermost layer of skin, is the gateway to daily contact with the outside world and the use part of cosmetics. The epidermis can be divided into five layers from outside to inside: stratum corneum, transparent layer, granular layer, spinous layer and basal layer.

Dermal: Belonging to connective tissue, it is located under the epidermis and interlaced with canine teeth of the epidermis. Dermal is mainly composed of collagen fibers, elastic fibers, reticular fibers and matrix, which plays a decisive role in the elasticity and luster of skin.

Subcutaneous tissue: also known as subcutaneous fat layer, its thickness is closely related to people's nutritional status, gender, age and location. People's fatness mainly depends on the amount of subcutaneous fat.

Skin accessory organs and their characteristics

Hair: hair grows on the surface of human body except palm and sole; Hair is composed of keratinized epidermal cells, which are divided into hair shafts and hair roots. The cross section of hair can be divided into three layers from the outside to the inside, namely epidermis layer, fur layer and hair pulp. Hair epidermis is composed of transparent keratinocytes arranged in scales, also called hair protective film, which can make hair shiny; Both cortical and medullary cells contain pigment particles, and the color of hair depends on the content of pigment particles.

Sweat gland: a kind of eccrine gland, which secretes sweat and moistens the skin without drying it; A kind of apocrine gland, the secretion is sticky, the secretion itself has no smell, and it smells after being decomposed by bacteria, commonly known as body odor.

Sebaceous glands: Sebaceous glands secrete sebum, which can lubricate skin and hair, but excessive secretion in some parts can easily lead to acne, dermatitis and seborrheic alopecia.

A: It consists of many layers of dense keratinocytes. A depression, color change or other abnormal changes may occur due to diseases, malnutrition, changes in environment and living habits.

What are the basic functions of skin?

Barrier function, sensory function, temperature regulation function, absorption function and participation in respiratory movement.

There are several types of skin.

From the perspective of medical beauty, it can be divided into oily skin, neutral skin, dry skin, mixed skin, sensitive skin and problem skin.

Basic principles of skin care

People's aging is inevitable, but it is also possible to delay aging and retain youth. Pay attention to be optimistic, ensure enough sleep time, drink more water, eat more fruits and vegetables, and learn to relax yourself. Are the key to delaying skin aging.

It is naturally important to maintain the beauty of skin and good living habits, but reasonable care is also essential. Here are some basic principles of skin care:

⑴ Keeping skin clean is the foundation of skin care. Usually, you can choose suitable cleaning products such as cleaning cream and facial cleanser, but you must pay attention to cleaning your face in the right way.

⑵ Promote skin metabolism. In daily life, massage can deliver enough nutrition and moisture to the skin to promote blood circulation and metabolism of the whole face. At the same time, massage can also open some occluded capillaries in skin muscles and increase muscle elasticity and tension.

⑶ Enhance skin resistance and protect skin from various factors. Sebum membrane is a natural barrier to protect skin. It is an important principle to keep the sebum membrane in a normal state. Cosmetic emulsion used daily is made by imitating the function of sebum membrane, and is considered as a supplement to sebum membrane, which can supplement the deficiency of sebum membrane and enhance the resistance of skin. It should be pointed out that the PH value of cleaning products for cleaning face must be compatible with your sebum membrane, otherwise it will damage the sebum membrane.

What is the standard of skin bodybuilding?

Bodybuilding skin can add beauty to the body, especially the bodybuilding of facial skin, which can leave a good impression on people. So, what kind of skin can be called bodybuilding? From the perspective of medical beauty, we can judge from the following aspects:

(1) Healthy and beautiful skin should be healthy skin. Healthy skin must meet three conditions: First, the skin color is normal. Yellow people should be reddish and yellowish. First, the skin is normal and there is no skin disease. The skin is not sensitive, greasy or dry, and there are no skin diseases such as acne and rosacea. Abundance means that the skin has vitality. Normal skin color is ruddy and shiny, so it is full of vitality. If it is blue-purple, sallow and pale, it lacks vitality.

(2) Clean the skin without dirt, spots and abnormal unevenness.

(3) Skin elasticity can be judged by skin elasticity test: lift the skin and then let it go. If you flatten it immediately, your skin will be elastic. If the skin is elastic, the surface will be smooth and soft without wrinkling or roughness. Generally speaking, young people have vigorous metabolism, rich dermal connective tissue matrix, sufficient water content, normal functions of various fibers and rich subcutaneous fat, which makes the skin look smooth and elastic. The skin of the elderly or people with diseases lacks elasticity.

(4) The moisture content of moist skin accounts for about a quarter of the total weight of human body, which is really an underground reservoir. If the moisture content of the skin decreases (such as aging, bad external conditions, etc.). ), the skin will become dry or even wrinkled, and such skin is a prerequisite for no aesthetic feeling.

In short, bodybuilding skin is ruddy and shiny, soft and delicate, firm and elastic, not rough and greasy, shiny and with few wrinkles. At the same time, the skin has good anti-aging ability and delays aging.

Factors affecting skin bodybuilding

Generally, there are the following points:

(1) There are three reasons why genetic factors affect skin bodybuilding: ① parents are in poor health. ② Congenital deficiency of offspring caused by consanguineous marriage. Unfortunately, embryonic development is affected, such as pregnant women taking drugs, drinking alcohol, smoking, malnutrition, etc., which leads to congenital dysplasia of offspring.

(2) Mental factors A person's mental state is not good, emotional instability and other instability will not only cause diseases, but also affect skin fitness, such as blue and red skin, even acne, dry skin and liver spots. If the next person is in love, the endocrine function is active and radiant.

(3) Food factors: Overeating, overeating, overeating and partial eclipse will lead to malnutrition, which will lead to premature skin aging.

(4) Physical and chemical factors, whether physical, chemical or mechanical, will affect the skin color. For example, ultraviolet radiation can darken the skin: asphalt and coal tar can be used to deepen the skin color; Scaring the skin will make the skin color blue; Smoking will accelerate the process of skin aging, and it is also the inducement or synergistic factor of many skin diseases, and it will also affect the appearance and shape of nails. Wind can destroy the epidermis and dermis of the skin, leading to dehydration and dry bath of the skin. The climate is dry and the temperature is too high. Air conditioning can also dry the skin.

(5) Iatrogenic factors mainly include the following factors: ① Improper massage can increase wrinkles; Excessive massage, random massage or techniques against the facial muscles are all improper massage. ② Improper or untimely treatment of facial dermatosis. ③ The method of losing weight is improper. For example, if you suddenly lose too much weight, your skin will lose a lot of water, become dry and wrinkle; Or improper diet, nutrient loss and wrinkles or other abnormal skin changes.

(6) Cosmetic factors There are many examples of improper use of cosmetics. According to the survey, chloasma on women's faces is more common in middle-aged women who like makeup. Common improper use of cosmetics are: ① frequent heavy makeup, too much powder, and reddish-brown cheeks; Excessive application of cosmetics hinders the secretion and excretion of sweat glands and sebaceous glands, resulting in furuncle, rash and miliaria. ② Abuse of cosmetics. For example, seborrheic dermatitis caused by oily skin using oily cosmetics. 3 indiscriminate use of nutritional skin care products. For example, adolescent girls used nutritional skin care products, which caused overnutrition and rough and swollen skin.

According to modern medical knowledge, the above factors affecting skin bodybuilding suggest the physiological characteristics of skin. If we take corresponding measures according to these physiological characteristics, we can achieve the goal of skin bodybuilding.

What is cosmetics? What is its scientific definition?

Cosmetics are the general name of products for cosmetic purposes. Throughout history, people from all over the world and all ethnic groups have used cosmetics. Although people have different ways to make themselves more attractive due to different cultural customs, some care products and beauty methods have been passed down from generation to generation. With the development of society, cosmetics have increasingly become an indispensable substance in people's daily activities. Cosmetics play an important role in protecting human skin health and beautifying bears. However, the scientific application of cosmetics is of great significance for keeping skin healthy. Therefore, we must make clear the scientific definition of cosmetics.

The word cosmetics in Greek manuscripts is KOSMETIKWS, which means "decoration", that is, the main remedy is to carry forward the advantages of human body and cover up the defects. Japan defines cosmetics as: "In order to keep the human body clean, beautify the human body, increase charm, change appearance, or keep the skin or hair healthy, articles used for the purpose of smearing or smearing on the body, or for the purpose of objective existence in a similar way are called cosmetics.

Japan defines cosmetics as: "In order to keep the human body clean, beautify the human body, increase charm, change appearance, or keep the skin or hair healthy, articles used for the purpose of smearing or smearing on the body, or for the purpose of objective existence in a similar way are called cosmetics. The US Food and Drug Administration's document on cosmetics said; " Cosmetics are substances introduced or smeared on the surface of human body by rubbing, pouring, spraying and painting. Without affecting the body structure and function, change the appearance to achieve the purpose of cleaning, beautifying and enhancing charm. "

In recent years, China has also made an exact explanation of the concept of cosmetics, as stated in the document of the US Food and Drug Administration on cosmetics; "Cosmetics are substances that are introduced or smeared on the surface of the human body by rubbing, pouring, spraying and painting. Without affecting the structure and function of the body, change the appearance to achieve the purpose of cleaning, beautifying and enhancing charm.

The definition of cosmetics in the Hygienic Standard for Cosmetics approved by the Ministry of Health 1987 is: "Cosmetics refer to daily chemical industrial products that are applied to any part of the human body (skin, hair, nails, lips, etc.). ) Clean, deodorize, protect skin, beautify and modify by rubbing, spraying or other similar methods. " Although the above definitions are not exactly the same, they are common, that is, cosmetics are skin care and beauty products, which can only be used on skin or waxy surfaces, and cannot be taken or injected. Only by understanding the basic concepts of cosmetics can we use all kinds of cosmetics correctly.

What is the new trend of cosmetic market at present?

At present, the international cosmetics market is developing rapidly, showing some new features:

Cosmetics with natural ingredients have become the mainstream of consumption. With the increasing demand for beauty and skin care, people have higher and higher requirements for the quality of cosmetics. They are worried that synthetic chemical cosmetics will cause bad irritation to the skin. More and more people are interested in pure natural pigment cosmetics. The grade of cosmetics is determined by the proportion of natural ingredients. The lower the processing length of raw materials and the higher the grade, the more popular they are in the market. Cosmetics containing chemical ingredients are gradually losing their market.

For example, a brand-new all-natural product-fruit acid series skin care and beauty cosmetics and aloe series skin care products. Fruit acid is an organic acid rich in water in natural fruits. Because of its small molecular weight, it is easy to be absorbed by the skin, which can weaken the adhesion of skin keratinocytes, make excessive accumulated keratinocytes fall off, improve the skin and make it moist and smooth. Aloe vera is a medicinal plant. According to modern scientific analysis, it contains vitamins E, K, D, C, B 1, B6, B 12, P, PP, B- carotene and so on. There are also 19 kinds of amino acids, soluble sugars, lactose-rich, mannose, grape bran and Arabic bran, which are rich in anthraquinone glycosides, protein, free amino acids, vitamins, active enzymes and 10 kinds of trace elements. Therefore, aloe protosweat can prevent pigment from forming and depositing on skin, prevent sunburn, whiten and moisturize skin, promote skin cell regeneration, and relieve pain and itching. It has remarkable effects on stopping bleeding, diminishing inflammation, improving keratinized skin, decomposing fat and losing weight. Therefore, fruit acid and aloe products are popular in the cosmetics market.

Cosmetics without perfume are very popular. The concept of "perfume-free cosmetics are pure in quality and beneficial to the skin" has been deeply rooted in people's hearts. Cosmetics without perfume are very popular in the market, especially young female consumers.

Cosmetics have an environmentally friendly style. In view of the increasingly serious environmental pollution in the world, some famous cosmetics manufacturers have gradually established the concept that cosmetics should have anti-pollution function. The produced skin care cosmetics not only have the cleaning and moisturizing functions of general care products, but also can form a protective layer on the face to prevent ultraviolet rays, polluted gases and dust from harming the skin. In addition, the taste of cosmetics also emphasizes the theme of environmental protection.

Health care, skin care, anti-aging and multi-purpose cosmetics are popular, and consumers' choice of cosmetics has developed from simple beauty decoration to new concepts such as nutrition and health care. At present, a new cosmetic wedding noodle, which integrates anti-aging, skin care and skin care in beauty beauty, has the functions of sun protection, freckle removal and wrinkle resistance, and is the latest goal pursued by consumers. The cosmetics I make in the market mainly include: shampoo and conditioner produced by Renjie Hairdressing Cosmetics Company in the United States, which can not only shampoo and protect hair, but also be applied to mosquito bites as an antipruritic agent; The moisturizing cream of American Paul and Moqie Hairdressing Cosmetics Company can not only nourish the skin, but also be used as massage cream, beauty moisturizing spray for hair and face and so on.

Men's cosmetics and baby skin care products are booming. Men's cosmetics such as "cologne" (cologne) and other perfumes are popular, and other beauty products have become a new trend and new pattern, and the sales of infant care products are also increasing greatly. According to the survey, there is a reverse consumption trend in the international cosmetics market. The "Gu Long" and "Bolong" on the men's cosmetics counter are extremely popular, and more than half of the customers are young girls and young women who love beauty. The poor reason may be that the perfume used by ladies is too fragrant, too sweet and too greasy, and the psychology of seeking novelty and novelty gradually turns to the surrounding markets, so the reverse consumption pattern is popular. Infant skin care products have also become women's favorite things. The reason may be that the female cosmetics market is mixed, and injuries occur from time to time. And more intuitive love of beauty tells them that infant cosmetics are mild and non-irritating, pure natural and unparalleled, so they are willing to join the infant cosmetics market and form a huge consumer group.

What kinds of anti-aging cosmetics are there? How is the research progress of natural anti-aging cosmetics?

According to the cosmetics market survey, anti-aging cosmetics are the most popular at present. The chemical and biological studies on human skin with modern science and technology show that 100g baby skin contains 9 ~ 12g cholesterol, while adult skin contains only 1.5g cholesterol. Therefore, adding natural drugs containing cholesterol raw materials and trace minerals, pantothenic acid, nicotinic acid and biotin, namely vitamin H and vitamin C, can prevent or delay skin aging. These are anti-aging cosmetics. At present, anti-aging cosmetics on the market can be mainly divided into: preparations based on nutritional ingredients, preparations based on moisturizing ingredients, preparations based on physiologically active substances, and preparations based on natural raw materials. At present, there are two kinds of creams in China's market that can prevent or delay skin aging to some extent: one is a cream containing all-trans retinoic acid (the intermediate metabolite of vitamin A), and the other is a sunscreen cream with high sunscreen efficiency. Because sun exposure is closely related to skin aging, sun protection is anti-aging.

Most chemists' cosmetics and their raw materials we use now are synthetic chemicals. Its curative effect and side effects have always been the focus of attention. At present, the international cosmetics market has a remarkable feature, that is, the proportion of cosmetics containing natural pharmaceutical ingredients has reached more than 60%. This phenomenon shows that the Chinese herbal medicine with lasting efficacy and strengthening the body resistance is an ideal anti-aging product. Natural anti-aging cosmetics are mainly composed of natural medicines (Chinese herbal medicines), and extracts of animals and plants are used as base or additives. According to the function of the added drugs, it can be divided into the following categories: cosmetics that can delay facial aging, cosmetics that can delay tissue aging, cosmetics that can prolong life, and cosmetics that can reverse aging.

In recent years, a large number of new materials have been used in the development of natural aging cosmetics abroad, and many valuable achievements have been made. For example, natural phosphorus-containing substances are made into lipid compounds by special methods, so that they have exactly the same structure as cell wax, so that they can flow and exchange essential substances and play an anti-aging role. In addition, vitamin B6, vitamin B complex and vitamin CX are added. Removing cream can promote skin metabolism and delay aging; Vitamin D2 and D3 combine with vitamin A, vitamin D2 combined with vitamin E can enhance the absorption capacity of skin, and vitamin H can enhance the production of sebum and cholesterol. Vitamin F has a certain therapeutic effect on unsaturated fatty acid deficiency.

The research and development of natural anti-aging cosmetics is a long-term project, which has penetrated into the study of skin types, biochemistry, physiology and various physical and chemical factors. The development and application of anti-aging drugs and cosmetics have opened up broad prospects for human anti-aging research.