Vitamins, translated as vitamins in Chinese, are commonly known as vitamins in Hong Kong and Taiwan, and are indispensable nutrients for human body. It was named by Polish scientist Fink, which means "life-sustaining nutrient". Vitamins are rare in the human body, but they have great physiological functions and must be indispensable. Because vitamins are often used as auxiliary components of some important enzymes in the body, they participate in a wide range of biochemical reactions and determine some very important metabolic processes. It can't be synthesized in human body, or it can't be synthesized in sufficient quantity, and it must be supplied by the outside world. Once a certain vitamin is lacking, the body will have corresponding metabolic disorder and show clinical symptoms without exception.
According to the solubility of vitamins, vitamins can be divided into fat-soluble vitamins and water-soluble vitamins. Fat-soluble vitamins include vitamins A, D, E and K, while water-soluble vitamins include vitamin C and B vitamins. Because there is an invisible sebum film outside the skin, the skin can basically absorb fat-soluble nutrients in skin care products for external use. As for water-soluble vitamins, due to their instability to light and heat, in most cases, water-soluble vitamins added to skin care products have improved. For example, vitamin C with its derivatives, on the one hand, can remain stable, on the other hand, is conducive to skin absorption.
Skin care and vitamin a
Vitamin A is a yellowish oily solution or a mixture of crystals and oil. It only exists in animal food; Carotene in plants can be converted into vitamin A in the body after being absorbed by the human body. Vitamin A can protect the epidermis of the skin and keep its function in a normal state. If it is lacking, it will cause dry skin and abnormal keratin metabolism, leading to the accumulation of dead skin cells. Specifically, vitamin A has the following main effects on the skin:
1. Carotene (the precursor of vitamin A, which can be converted into vitamin A in vivo) can resist the oxidative damage of free radicals to cells from different parts of the body, enhance the body's antioxidant capacity and reduce the harm of free radicals.
2. Helps keep the skin soft and plump, and improves the water-locking function of the skin.
3. It has obvious anti-keratinization effect, can delay skin aging and regulate the division and development of skin cells.
4. It helps to treat acne locally and prevent rough and chapped skin, chilblain and dandruff.
5. Helps to promote metabolism and keep skin young.
Based on the above functions of vitamin A, it is widely used in skin care products such as moisturizing, conditioning and delaying aging.
Skin care and vitamin c
1. Excellent antioxidants help to reduce the damage of free radicals to the skin, help to reduce wrinkles and improve the skin structure.
2. Inhibition of abnormal pigment deposition and tyrosinase activity on the skin is helpful to reduce dopa pigment (the intermediate of tyrosine transforming into melanin), thus reducing the formation of melanin.
3. Mainly used to synthesize collagen. Experiments show that adding vitamin C to skin cell culture can greatly increase the synthesis of collagen.
Because vitamin C has the above excellent efficacy, it is widely used in whitening and antioxidant beauty and skin care products.