Over-prosperity, the truly effective whitening, light spot ingredient-kojic acid
Cosmetics is a fashion and fashion industry. Every year, new ingredients will come out. Every one is in the lead for three or five years. You can sing and I will be on the stage. Many very popular ingredients, with the passage of time, are gradually forgotten. But some ingredients, though fading, still stand firm and are still being applied. These ingredients certainly have their unique effects. Among many classical ingredients, "kojic acid" is one of them.
The experience of kojic acid in cosmetic ingredients is as frustrating as many people's lives. From the beginning, to the fall of the altar, it was forbidden to use, to the later rebellion, it was re-applied, around decades. Now, the study of kojic acid has been very detailed. Today I'm going to talk about kojic acid.
About "kojic acid"
Kojic acid can be produced by fermentation of Aspergillus (a fungus) with various substances. Pure kojic acid is mainly produced by fermentation of glucose. Kojic acid is a small molecular component with a molecular weight of 142.22, which can be directly absorbed through the skin. Kojic acid is the English name of kojic acid. Ingredient alias: 2-hydroxymethyl-5-hydroxy-γ - pyranone.
Since its discovery, kojic acid has been first used in food, medicine, agriculture and other fields. In the field of food, it can be used as food additive to keep fresh, preserve and antioxidant. Later, some research institutes found that kojic acid had good whitening effect and could dilute the spots. After the discovery of this application, "kojic acid" began to be used as skin whitening agent, widely used in whitening, light spot products.
We know that "melanin" is the core ingredient that causes skin darkening and spots. Inhibiting the production of melanin can play a whitening and light spot effect. In the process of melanin production, tyrosinase is an indispensable catalyst. Kojic acid and tyrosinase can grab copper ions, deactivate tyrosinase, block the production of melanin, and achieve the purpose of whitening and light spots.
Some small partners do not have a special understanding of the ingredients, see that "kojic acid" has "acid", immediately linked with "fruit acid". In fact, the whitening mechanism of kojic acid and fructonic acid is completely different. They do not exfoliate keratinocytes or make the cuticle thinner.
After years of comparative research, as well as the actual experience of a large number of consumers, it is recognized that "kojic acid" has excellent whitening and light spot effect. It used to be the gold standard for whitening after "hydroquinone". So many whitening materials in the promotion now, often with "inhibition of tyrosinase is how many times the effect of kojic acid" as a slogan for publicity. Many dermatologists in Europe and the United States use 2-4% kojic acid to treat chloasma, and have achieved good results. Interested partners can search, whether in English or Chinese literature, there are many discussions about "kojic acid" in the treatment of chloasma.
Safety of kojic acid
Since kojic acid works so well, why was it banned later? As we said before, kojic acid is also widely used in food industry. But early extraction technology is not good. In Japan, some low-grade kojic acid containing unknown impurities can blacken shrimp and COD seeds, and people begin to doubt the safety of kojic acid.
Between 1995 and 2003, the Japanese Institute of Health Sciences completed the mutagenicity and carcinogenicity experiments of kojic acid. Most of the results were negative (representing non-carcinogenic), but a small number of animals showed positive (carcinogenic) thyroid and liver reactions. Although it's a small amount, it's a matter of human health, not sloppy. In addition, many cosmetics manufacturers in order to achieve rapid results, excessive use of high concentration of kojic acid, on the "kojic acid" will sensitize, causing dermatitis, a large number of adverse reactions. In early 2003, kojic acid, an effective whitening agent that has been used for more than 20 years in Japan, was banned from adding to food and frozen the sale of maintenance products containing kojic acid. Because of safety concerns, kojic acid has been quiet in the market for some time.
Later, Japan reopened its cosmetics in 2005. Although there was no specific restriction, the recommended dosage ranged from 0.1% to 1%.
As for the safety of kojic acid, whether it is carcinogenic or not, scholars around the world have done a lot of research. Interested partners can search for it by themselves. The information in English is very detailed. Zhan Biao briefly introduced the final conclusion: kojic acid is not an acute, chronic, reproductive toxic substance. Although some animal data suggest that cancer promotes and weakens carcinogenesis, kojic acid is absorbed very slowly from human skin to circulation, and may not reach the threshold of these effects. Kojic acid is safe below 2% in cosmetics.
Studies have shown that the use of cream containing 1% lactic acid on the face, respectively in 0.5, 1, 1.5, 3, 6, 12, 24 hours to test the content of kojic acid in the blood of users, all concentrations of plasma is only slightly higher than the normal value of 1 ng, no adverse reactions were observed. Kojic acid enters the blood very low through the skin and has little effect on the human body. It was proved that kojic acid had no reproductive toxicity and would not cause fetal distortion or produce reproductive toxicity through rat experiments. And this experiment belongs to feeding, if it is applied through the skin, don't worry about it.
In practice, a large number of statistical data show that consumers who do not use kojic acid for a long time have abnormal liver function, including liver tumors and skin cancer.
With regard to the safety of kojic acid, after decades of research, it can be basically concluded that the application of kojic acid in cosmetics is safe within the limited range, so don't worry about it.
Sensitization of kojic acid
Kojic acid is often criticized for its safety and allergenicity. There are also a lot of reports about the allergenicity of kojic acid, so what is the real situation?
Independent research institutes at home and abroad have also done a lot of tests. A comparative test was made between 1% and 3% kojic acid solution and SLS (sodium lauryl sulfate, a cleaning ingredient commonly found in face wash milk). It is concluded that kojic acid is a mild skin irritant. This conclusion does not take into account the use of kojic acid in cosmetics, will add various components, reduce the irritation of kojic acid.
In the patch test of 220 female patients, there was no evidence that less than 2% of kojic acid products could cause contact dermatitis. In terms of phototoxicity, it was confirmed that kojic acid had no phototoxicity and did not cause delayed contact reaction. Therefore, products containing kojic acid can be used during the day.
These studies are all conducted by independent research institutes. They have no direct interest relationship and are highly credible. So why are there so many reports of kojic acid allergy?
Zhen Biao can talk about some of the insights he knows. Foreign countries do not understand, as far as domestic, "kojic acid" used to be a red fried chicken in whitening and freckle-removing fields, many manufacturers have introduced products containing kojic acid. If within the limits, moderation is not a problem. However, consumers appear stains, the general mentality is more impatient, need to solve the problem quickly. Many manufacturers in order to meet the needs of consumers, kojic acid added more than 2%, or even more than 4%, too high concentration of kojic acid will stimulate the skin, causing allergic reactions. Some manufacturers add hormones to their products to inhibit allergic reactions. But long-term use, there are always hormones can not suppress that day, skin problems began to erupt, serious can cause facial dermatitis.
Together with the ban on kojic acid in Japan in 2003, negative news began to circulate, and most consumers did not know the truth. A good ingredient, so that consumers and businesses to play to death. New whitening ingredients are constantly emerging. Domestic manufacturers are good at keeping up with the trend. There are few products that really use kojic acid. As long as Japan's high-end high-wire group is still in use in high-end brands, such as the noble woman product "Daike Yingying Essence".
Stability of kojic acid
"Kojic acid" was abandoned by most manufacturers, in addition to the above negative news, there is also an important reason is "stability". Like all whitening products, "kojic acid" is light-proof and high temperature-prone to decomposition and oxidation in these environments.
How to make kojic acid products which are stable during shelf life and will not be oxidized and decomposed is a great challenge to the formulator. Kojic acid has a high requirement for PH. It can withstand the challenge of high temperature in the environment with PH value 4. If the product's PH value exceeds 5, it is easy to oxidize and deteriorate.
Therefore, if you use products containing kojic acid during the day, you should do a good job of sun protection, protect kojic acid on the skin. If it is not used for a long time, it will be helpful for the activity of moisturizing kojic acid and prolong the shelf life if it is placed in the refrigerator for refrigeration.
Kojic acid products on the market
The famous kojic acid product on the market, "Daike Yingyun Baijingye" is a kind of product, which has developed for several generations. Net content: 40ml, retail price: 1050.00 yuan, as follows:
This whitening essence contains 1% kojic acid, with a variety of antioxidants. There's no time for analysis today. I'll write more later.
Another popular product containing kojic acid is "Korea Dongxing pharmaceutical Lang Si Dongxing kojic acid small black bottle cream", net content: 70g, retail price: 238 yuan. The following picture:
This cream has not yet officially entered the country, sales channels are more complex, touted as freckle artifact, all kinds of exaggerated hype, the use of experience everywhere. Zhenbiao could not find his full ingredient table, but from the advertising materials and a composition table on a commercial website, kojic acid content of 1%, has whitening effect, but also has the role of light spots, but for more serious spots, the effect will not be very good.
Zhen's own "rance Shi Ni Tong Shuang Xie Huan Cai essence", one of the important whitening ingredients is also "kojic acid", the content of 1%. The product is being manufactured in the factory. I will meet you soon. Let me put out a picture first. The following picture:
To sum up, "kojic acid" is an excellent whitening, light spot ingredient, after decades of research and application, is a classic ingredient tested. As long as the dosage is within a certain range, there is no problem of safety and no allergic reaction. Kojic acid can really whiten, not the brightening feeling of VC. If the whitening effect of VC is expressed by transparency, the effect of kojic acid is milky white. The combination of the two is the best.
Company name:Hunan dye natural resource inc