Hyaluronic acid is a secret weapon for the skin.
Hyaluronic acid (HA), is a frequent visitor in cosmetic advertisements. In 1937, Professor Mayer of Ophthalmology at Columbia University isolated hyaluronic acid from bovine vitreous body for the first time. In subsequent studies, scientists discovered that it is a linear macromolecular polysaccharide, which is composed of two monosaccharides, glucuronic acid and acetaminoglucose. In aqueous solutions, hyaluronic acid sugar chains cross-link each other vertically and horizontally to form a network that acts like a sponge that absorbs and retains large amounts of water.
In fact, hyaluronic acid is one of the inherent components of the human body. It is estimated that an adult body contains about 15 grams of hyaluronic acid. The most important function it plays is water holding. Hyaluronic acid content decreases with age. If the relative content of sodium hyaluronate in the 20-year-old body is set to 100, then in the 30, 50, 60-year-old, the number dropped to 65, 45, 25, respectively. The skin also becomes rough and wrinkled.
When the magic effect of hyaluronic acid was excavated, it quickly became a beauty product. Injection, external application and oral administration are the three main ways of using hyaluronic acid for cosmetics.
Injection hyaluronic acid was approved by the US Food and Drug Administration (FDA) in 2003 for skin rhytidectomy. To put it simply, it is to want where to go and where to go. What’s more remarkable is that hyaluronic acid is a human body with good biocompatibility. Hyaluronic acid injected into the body slowly fuses with the original hyaluronic acid and is metabolized slowly, lasting 6 months to 1 year at a time. It is worth noting that high purity products must be selected for in vivo injection, otherwise impurities in them are likely to trigger an immune response, but let the user suffer the opposite consequences.
Hyaluronic acid moisturizing properties make it also widely used in skin care products. Some manufacturers even provide hyaluronic acid solution for consumers. Its concentration is high, generally, need to be diluted after another use. Direct use of a higher concentration of the solution will not play a moisturizing effect on the face skin, but because of hyaluronic acid hygroscopicity to absorb the original skin moisture.
However, the injection of hyaluronic acid rhytidectomy is a physical consequence. When applied topically, the macromolecules are almost impossible to be absorbed through the skin, and therefore can not play the role of injection. Its main advantage is to provide a water-rich environment for the skin, can prevent the adverse effects of dry external environment on the skin, has an objective anti-wrinkle effect, but for existing wrinkles, external application of hyaluronic acid is not effective.
Some health products labeled with hyaluronic acid have been advertised as “skin-care” because oral hyaluronic acid intake can be distributed in the epidermis and dermis along with the circulatory system to make up for the shortcomings. Others believe that the decomposition of oral products will increase the level of precursors when hyaluronic acid is synthesized, thereby increasing the level of hyaluronic acid. Add skin content.
The reason for the former is hardly refutable. The molecular weight of hyaluronic acid is about hundreds of thousands, and it is almost impossible for the giant molecule to distribute to the skin by the oral route through the circulatory system. The decomposition and synthesis of hyaluronic acid is a complex biochemical process. The final products of oral uptake and natural hyaluronic acid degradation in vivo are carbon dioxide and water. The basic materials, glucuronic acid, and acetylglucosamine, are linked alternately by hyaluronic acid synthase. These two substances are all derived from glucose. The activity and content of synthetase are the keys to the production of hyaluronic acid. So instead of taking hyaluronic acid supplements, eat two large white steamed bread — starches with glucose in them.
Stanford Chemicals 