Original title: Silicone oil "murder" hairline? You may not know the truth about these shampoos
"No silicone oil, no irritation!" "Natural extracts must be better than chemical substances!" In recent years, the rumors that "silicone oil added in traditional shampoos can clog pores, cause hair loss, and even cause cancer." Shampoo "falls out of favor". Silicone-free shampoos quickly occupy the market. Even though they are much more expensive than silicone-containing shampoos, they still attract consumers.
So, what exactly is silicone oil? Is it really the culprit that causes hair loss, skin irritation and even cancer? Is the zero-silicone oil-free washing and care products that consumers spend at a high price necessarily applicable? With these questions, the reporter visited Sun Jie, a pharmacist in charge of the Nanjing Institute of Dermatology, Chinese Academy of Medical Sciences, and listened to what the professionals said.
Silicone oil can effectively relieve hair damage
"Silicone oil is an organosiloxane, and dimethyl silicone oil is more commonly used in the washing and cosmetic industries." Sun Jie told a reporter from Science and Technology Daily.
In the chemical industry, silicone oil is actually a general term for polydimethylsiloxane, cyclodimethylsiloxane or its derivatives. Silicone oil is a non-volatile, transparent, non-toxic, non-corrosive liquid with stable chemical properties and high safety.
In shampoo, the scientific name of silicone oil is "polydimethylsiloxane", which has good viscosity and ductility, that is to say, it is very similar to oils extracted from natural plants.
Our ancestors first used natural plant extracts to clean their hair and skin. With the development of the chemical industry and the continuous improvement of people's requirements for washing and care products, silicone oil has begun to be used in shampoo products, and it has a history of 70 years.
Why add silicone oil to shampoo? This starts with the structure of the hair.
Our hair grows from the hair follicles of the scalp, and its main component is keratin. There are many hair scales on each hair. The outermost layer of hair scales consists of 7-10 layers of dead cells, covering the surface of the hair to protect the core. The healthy hair scales are intact and compliant, so the hair surface is smooth and looks shiny and bright.
Sun Jie told reporters that when shampooing hair, the lubricating and protective oils attached to the hair scales will be washed away, and the hair scales will be warped when combing, which increases the friction between the hair and makes it easy to make the hair. Entangled together, thereby exacerbating the damage to the hair scales. If you dye your hair perm, it will also spread the hair scales and your hair will look dry and dull.
Silicone oil can be absorbed together with the hair, fill up the unevenness caused by the bulge of the hair scales, reduce the friction between the hair strands, make the hair easy to comb and have smoothness, and effectively relieve the damage of the hair.
At the same time, silicone oil is also a skin moisturizing ingredient, which can cover the skin to form a protective layer to prevent the skin from dispersing and losing water. It is often used in moisturizers.
Severe hair loss is not the fault of silicone oil
There have always been many misunderstandings about silicone oil, such as skin irritation, allergies, and even rumors that silicone oil is toxic and carcinogenic.
"Silicone oil is widely used in cosmetics or skin care products, and it has been approved by the regulatory authorities of various countries around the world to be used in cosmetics." Sun Jie pointed out that silicone oil itself is non-toxic, odorless, and less likely to cause skin irritation and allergies.
There have been rumors that: "Silicone oil is carcinogenic, and the US Food and Drug Administration (FDA) has banned silicone oil." The reporter checked the FDA official website and found that dimethicone with the code 009006659 is dimethyl silicone oil, which is clearly used by the FDA in cosmetics. Ingredients, and many international well-known brands are clearly marked as containing silicone oil.
In addition, the reporter checked the literature and found no reports of carcinogenic and teratogenic silicone oil.
"The U.S. Cosmetic Ingredient Review (CIR) expert group evaluated the safety of silicone oil preparations in 2003. Most of the products evaluated by it have a silicone oil concentration of ≤15%. The expert group believes that the molecular weight of silicone oil is large and will not be absorbed by the skin. Animals or humans have carcinogenic, mutagenic and teratogenic toxic reactions.” Sun Jie said that in 2014, the CIR expert group evaluated 62 cosmetics containing simethicone cross-linked polymers and considered them to be safe and not carcinogenic. sex.
In addition, the reporter consulted China's national standard "GB/T29679-2013" for shampoo and shampoo, and there is no restriction on the use of silicone oil. Therefore, there is no need to "look at silicone oil and change the color."
In recent years, many people have had "Mediterranean" hairstyles under the age of thirty. Therefore, some people think that this is caused by the use of shampoo containing silicone oil.
"It is normal for adults to lose 70-100 hairs a day, and it is obvious that they lose a lot, or they need to be noticed when they fall in pieces." Sun Jie said.
Silicone oil is insoluble in water, and it will clog the scalp hair follicles if it is not cleaned for a long time. However, the concentration of silicone oil in shampoo products is only about 1%. There is only 0.1g of silicone oil (about 0.1ml) in 10ml of shampoo. On the surface of the hair, the possibility of clogging the hair follicles is minimal, and there is no report that silicone oil can block the hair follicles.
According to Sun Jie, in recent years, improved water-soluble silicone oils have been used in care products, so that during shampooing, silicone oils can be more effectively attached to the hair with fewer residues on the skin.
In addition, the human scalp can secrete up to 1 gram of oil a day, and 0.1 gram of silicone oil is really dwarfed by the daily oil output of the scalp. Moreover, the grease is constantly drained out, even if a little silicone oil enters the pores, it is easy to drain with the grease.
Sun Jie told reporters that in modern society, people working overtime, staying up late, emotional stress, endocrine disorders, stimulating eating, dieting, etc. are all causes of hair loss. Silicone oil undoubtedly carries a "big black pot" in this regard.