Overview of Functional Cosmetics 1. 1 Definition of Functional Cosmetics In the past 10 years, due to the innovation of cosmetics and medicine industries and the change of consumers' attitudes towards cosmetics, the boundary between cosmetics and medicines has become more blurred because of the intersection, as shown in figure 1- 1. Because of this crossover, new categories of cosmetics and similar drugs have emerged. For example, although the US Food and Drug Administration (FDA) does not define cosmetics as an independent category, the term has been derived and eagerly used by cosmetics manufacturers to describe a class of products that combine cosmetics and drugs. Every day, more and more terms are used to describe what we call functional cosmetics. These include: beauty supplements; Active cosmetics; Efficacy cosmetics; Bioactive cosmetics; Plant cosmetics; Efficacy cosmetic skin therapeutic agent; Dermatology; Beauty drugs; Therapeutic cosmetics. Of course, these terms are not all the same. In some cases, users are trying to correctly distinguish certain product categories; In other cases, users may just "put new wine into old bottles". Beauty supplements are basically natural nutrition and health products, which produce beauty effects through oral administration. They are usually used in the form of capsules, but sometimes they are also used in the form of decoction or even tincture. Active cosmetics include "active" ingredients that may not produce many satisfactory health benefits. However, the use of terms such as functional cosmetics or functional cosmetics means that they show more useful effects than ordinary cosmetics. For example, skin therapeutics and skin drugs can only be simply classified as a small category of functional cosmetics, while beauty drugs are defined as a combination of cosmetics and drugs by the US Food and Drug Administration. Such products, including fluoride toothpaste and dandruff shampoo, must also comply with human health, cosmetic hygiene and safety regulations. Due to the differences between the existing cosmetic hygiene and safety regulations in the world and the global culture, there are many different interpretations of functional cosmetics. Different countries are using the above phrases and terms to express functional cosmetics. .2 History of Functional Cosmetics Although the term functional cosmetics was first put forward by American dermatologist Albert Cligman, M.D. in 1970s, Egyptians were the first people to realize that cosmetics can have health care functions. Archaeologists unearthed some ancient cosmetic jars with hieroglyphics that read: "Good for eyesight" and "Stop bleeding". Medical papyrus written in BC 1600 often involves many functional cosmetics. Especially popular are preparations using honey and milk, which are said to help treat skin diseases. Other products made of frankincense, vegetable oil and paraffin in equal proportions claim to eliminate facial wrinkles. For many medieval Arab doctors and their European counterparts, cosmetics, essences and herbs are no different. Their research and trial production also cover these disciplines. The separation of cosmetics and washing industries from the medical field occurred in the19th century, when the modern pharmaceutical industry began to develop and the first government decree to control drug sales was implemented. In recent 50 years, doctors and the public have paid too much attention to cosmetics, which has led to allergic reactions, which is ironic. The role of cosmetics as an effective auxiliary means of treatment has been neglected until the late 1970s and early 1980s. Krigman rekindled people's interest in cosmetics by developing preparations that can improve the appearance of ultraviolet damaged skin and resist skin wrinkles. Here, he uses retinoic acid as the active ingredient. Retinoic acid has been proved to have the ability to eliminate fine wrinkles, reduce aging keratinization and promote collagen formation. Krigman believes that the new cosmetic technology "makes it possible to add an infinite number of active substances to skin care products, which come from natural resources-from plants, oceans, the earth and the universe, including an exciting list of substances synthesized by chemists. For example, vitamins and antioxidants, anti-inflammatory, mood-affecting fragrance, placenta, amniotic fluid serum and many hormones have a wide range of choices. " 1.3 The types of functional cosmetics (1) are divided into the following parts according to common use: skin care: including sunscreen and other skin care products; Hair care: including shampoo, conditioner and hair care products to protect scalp health; Body care: including deodorant and various personal care products; Beauty care: including armor, eye protection and beauty products. Functional cosmetics are mostly skin care products, with special emphasis on sunscreen products; Secondly, the second category is hair care products. (2) According to gender usage, functional cosmetics are divided into: among men, the key areas of potential functional cosmetics are: hair regeneration, anti-aging, dandruff removal, antiperspirant, anti-dermatitis, anti-tooth corrosion, anti-beriberi and astringent; Among women, functional cosmetics are mostly used for anti-wrinkle, breast augmentation, slimming (anti-cellulite), hair removal, oral hygiene, skin browning prevention, skin whitening, cell regeneration and recovery, anti-free radicals and anti-varicose veins. Nowadays, with the aging of the world population, people associate youth with beauty. For women, the continuous use of anti-aging cream and skin whitening products will constitute a growing cosmetic consumption market. In recent decades, some of the most popular and controversial functional cosmetics contain fruit acids: α-hydroxy acid (AHA) and β-hydroxy acid (BHA), which are very popular "anti-aging substances". Red blood is another difficult problem in beauty. In this field, biological cosmetics and plant cosmetics are becoming more and more popular. Many plant medicinal materials, especially grape leaf extract products, have been successfully applied, and local creams to slow down red blood silk are gradually entering the market. (it will continue to be serialized in the future)-. Usually, sunscreen factors are added to the formula of such whitening products. 2. Accelerate the metabolism of pigmented keratinocytes: α hydroxy acid and alcohol A can promote the metabolism of skin. They can help eliminate pigmented cells, make the skin look brighter, and accelerate the growth and division of constantly updated grass-roots cells. In this way, the number of melanocytes entering adjacent cells will be less, and the skin will turn white obviously. 3. Reduce the biosynthesis of new pigments: As for the action process of these components, most of the components in the products on the market at present play their roles by inhibiting tyrosinase. Usually, this kind of derivatives can't give consideration to both safety and effectiveness. Taking hydroquinone as an example, the active ingredient is gradually abandoned because it is said to be toxic. Therefore, in recent years, the ingredients of a new generation of functional whitening products have become the focus of attention and development by many people in the industry-arbutin: its structure is hydroquinone glycoside, which acts by inhibiting tyrosinase; Its irritation and sensitivity are much less than that of hydroquinone. The concentration used is between 1% and 10%, preferably higher than 5%. Soluble in water, stabilizer should be added to avoid discoloration of the final formula. Kojic acid: Its function was discovered when observing the white-handed of Japanese sake brewers. Can effectively inhibit tyrosinase, soluble in water, the concentration is between 1%-3%. Non-toxic and less irritating after use, so it is used as an antioxidant in Asian food industry. However, when used in whitening products, the formula has stability problems, which will make the products added with kojic acid turn yellow-brown. Therefore, antioxidants are added to beauty cosmetics containing kojic acid. Kojic acid palmitate: A fat-soluble component derived from kojic acid. Compared with the sunscreen emulsion and preservative that may be added in its formula, its advantage is that it does not affect its activity. Although it is speculated that it can inhibit tyrosinase, the exact process of action is not fully understood in the industry. However, human experiments show that it is stable and non-irritating. Vitamin C derivatives: Vitamin C can effectively inhibit tyrosinase, but it has no corresponding whitening effect. Therefore, people in the industry infer that its antioxidant effect reduces and decomposes melanin, thus playing a whitening role. Because of its unstable nature, it is necessary to add other ingredients to its formula to maintain its stability, but its efficacy may be reduced. It is worth mentioning that magnesium phosphate of vitamin C is a relatively stable derivative of vitamin C, which is easily soluble in water. When used as a skin whitening ingredient, the concentration is between 5% and 10%. It has the functions of brightening skin and antioxidation, and can stimulate the synthesis of collagen, and is also commonly used in anti-aging skin care products. Azelaic acid derivative: This acid is naturally produced by the yeast of dermatophytes causing tinea versicolor, and pale spots will appear on the skin through the action of this molecule. Is an effective inhibitor of oxidase, so it can also inhibit tyrosinase. It is insensitive to light and has good compatibility with skin, but it is difficult to dissolve and is inconvenient to combine with emulsion. In recent years, the derivative azepamine has obvious whitening effect in its gum with 3% concentration. Plant extracts: Many plant extracts have the function of whitening skin, but the current problem is how to correctly identify the effective components. For example, Pyracantha fortuneana (a derivative of Rosaceae) in China has whitening effect, tyrosinase inhibition and antihistamine effect. Although it is not clear whether these effects come from the same component in the extract, it is certain that it contains polyphenols, an essential oil of Glycyrrhiza glabra, which has been studied and dispersed in many different plants and proved to have whitening effect. In a word, the efficacy of whitening formula mainly depends on the types of ingredients, and people can evaluate it through test tubes and human tests. However, some research results show that the nursing efficacy produced by the combination of several active ingredients can be higher than the sum of the efficacy of a single ingredient. Some ingredients, such as lipoic acid, sorbic acid, glucosamine, glutathione, cysteine, etc., have little whitening effect, but combined use can improve the efficacy.