Science and Technology Daily reporter Zhang Ye "no silicone oil, no stimulation!" "Natural extracts must be better than chemicals!" In recent years, about "the silicon oil added in the traditional shampoo will block the pores, cause hair loss, and even cause cancer." Hearsay, let the shampoo that adds silicon oil "fall out of favor". Silicone free shampoo quickly occupied the market, even though it was much more expensive than silicone containing shampoo in price, but it still attracted the attention of consumers.
So, what is silicone oil? Is it really the cause of hair loss, skin irritation and even cancer? Is the zero silicone oil washing and care product that consumers pay a high price applicable? With these questions, the reporter visited Sun Jie, a pharmacist in charge of Nanjing Institute of Dermatology, Chinese Academy of Medical Sciences, to hear what the professionals said.
Silicone oil can effectively alleviate hair damage
"Silicone oil is a kind of organosiloxane, which is widely used in the washing and cosmetics industry." Sun Jie told Science and technology daily.
In the chemical industry, silicone oil is a general term for polydimethylsiloxane, cyclodimethylsiloxane or their 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 the oil extracted from natural plants.
Our ancestors first used natural plant extracts to clean hair and skin. With the development of chemical industry and the continuous improvement of people's requirements for shampoo and care products, silicone oil has been applied to shampoo products for 70 years.
Why add silicone oil to shampoo? This starts with the structure of the hair.
Our hair grows out of the hair follicles of the scalp and is mainly composed of keratin. There are many scales on each hair. The outer layer of hair scale is 7-10 layers of dead cells, covering the hair surface to protect the hair core. The healthy hair scale is complete and fit, so the hair surface is smooth and looks bright.
Sun Jie told reporters that when washing hair, the grease attached to the hair scales that plays a lubricating and protective role will be washed away, and when combing hair, the hair scales will rise up, which increases the friction between the hair, which is easy to entangle the hair together, thus aggravating the damage of the hair scales. If the hair is dyed and permed, the scales will open and the hair will look dry and lusterless.
The silicone oil can be absorbed with hair, fill up the uneven caused by the hair scale bulge, reduce the friction between the hair, make the hair easy to comb and have smoothness, and effectively alleviate the damage of the hair.
At the same time, silicone oil is also a skin moisturizing component, which can cover the skin to form a protective layer and prevent the loss of skin moisture. It is widely used in moisturizers.
Serious hair loss is not the fault of silicone oil
For a long time, there are many misunderstandings about silicone oil, such as irritating the skin, causing allergies, and even hears the rumors that silicone oil is toxic and carcinogenic.
"Silicone oil is widely used in cosmetics or skin care products, and has been approved by regulatory authorities around the world. It can be used in cosmetics." Sun Jie pointed out that silicone oil itself is non-toxic and tasteless, and less causes skin irritation and allergy.
There was a rumor that "silicone oil causes cancer, and the US Food and Drug Administration (FDA) has banned silicone oil." The reporter inquired the FDA website and found that the dimethicone with the code of 009006659 was dimethylsilicone oil, which was clearly identified by the FDA as an ingredient that could be used in cosmetics, and was clearly identified as containing silicone oil in several international famous brands.
In addition, the reporter looked up the literature, also did not find the report of carcinogenesis and teratogenesis of silicone oil.
"The expert group of the American cosmetic ingredient review (CIR) evaluated the safety of silicone oil preparations in 2003, and the concentration of silicone oil in the products assessed was mostly ≤ 15%. The expert group believed that silicone oil had a large molecular weight and would not be absorbed by the skin, and no toxic reaction to animals or people caused by carcinogenic mutation and teratogenicity was found." Sun Jie said that in 2014, the CIR expert group evaluated 62 cosmetics containing dimethylsilicone oil cross-linked polymers and found them to be safe and non carcinogenic.
In addition, the reporter referred to China's national standard "GB / t29679-2013" on shampoo and shampoo, which did not limit the use of silicone oil. Therefore, there is no need to "look at silicone oil and color change".
In recent years, many people have "Mediterranean" hairstyles when they are less than 30 years old. Therefore, it is believed that this is caused by the use of shampoo containing silicone oil.
"It's normal for adults to lose 70-100 hairs a day. It's obvious that a lot of hair is lost, or a piece of hair needs to be noticed." Sun Jie said.
Silicone oil is insoluble in water. If it is not cleaned for a long time, it will block scalp hair follicles. However, the concentration of silicone oil in shampoo is only about 1%, and only 0.1g of silicone oil (about 0.1ml) in 10ml of shampoo. After washing, most of silicone oil will be adsorbed on the hair surface. The possibility of blocking hair follicles is very small, and there is no literature report that silicone oil will block hair follicles.
Sun Jie said that in recent years, the improved water-soluble silicone oil is applied in the washing and care products, so that when washing hair, the silicone oil can attach to the hair more effectively, and the residue on the skin is less.
In addition, the human scalp can secrete up to 1g of oil a day, and 0.1g of silicone oil is really dwarfed by the amount of oil produced by the scalp in a day. And the grease is constantly discharged, even if a little silicone oil enters the pores, it is easy to follow the grease.
Sun Jie told reporters that in modern society, people's overtime, emotional tension, endocrine disorders, stimulating diet, diet and so on are all the causes of hair loss, and silicone oil is undoubtedly a "big black pot" in this regard.
Hair quality should be taken into consideration in choosing washing and protecting products
In recent years, silicone free shampoo has rapidly occupied the market. Even though the price is 5-10 times more expensive than silicone oil shampoo, consumers are still scrambling for it.
Intensive advertising, the "Force recommendation" of online Red live delivery, has focused consumers' attention on the silicone free shampoo, but many consumers haven't figured out what it means to have silicone free shampoo, and see others use it for themselves. As a result, some people have more serious oil discharge, and some people have increased the dryness of the scalp and hair bifurcations.
"Zero silicone shampoo is also developed by manufacturers to meet the needs of Western consumers. Most of the European and American people have soft hair and do not need to add a lot of lubricating grease." Sun Jie explained that, however, the hair quality of yellow people is hard, and many people often dye and perm it, so how to choose it depends on the hair quality.
In addition, even though many products claim that there is no silicone oil in shampoo, they also add other vegetable oil ingredients. These vegetable oils may also block hair follicles. At the same time, some people may use it to stimulate the scalp and produce allergic reactions.
So Sun Jie suggested,
Consumers should choose the right shampoo according to their own situation. If you often need perm, hair dye and hair care, you can choose the shampoo with silicone oil;
If you are oily skin, hair, hair volume is less, you can choose a shampoo without silicone oil to produce a relatively fluffy hair effect.
For people with dry scalp, less oil secretion, rough hair or long-term scalding and dyeing, you can use silicone oil shampoo to make hair smooth and easy to take care of;
Some hair quality slants dry, often perm dye of female, choose to contain silicon oil shampoo also more appropriate.
Sun Jie pointed out that both shampoo containing silicone oil and shampoo without silicone oil have their own advantages, and the one suitable for their hair quality is the best. Therefore, you can choose the shampoo with or without silicone oil according to your own needs.
Tip: wash your hair properly and don't step on the puddle
How about using hot water to wash your hair?
If the water temperature is too high, it is easy to damage the hair scales and scalp. For people with oily hair, high temperature can also stimulate sebaceous glands, aggravating hair oil.
Suggestion: water temperature should be close to human body temperature.
Shampoo directly on your hair?
Directly pour shampoo on the hair, it will produce greater stimulation to the scalp, and even cause inflammation.
Suggestion: rub the shampoo out of the foam and rub it on the hair.
More hair conditioner, more moisturizing?
Too much hair conditioner or staying on the head for too long may bring burden to the scalp and aggravate the problem of hair and scalp.
Suggestion: apply it to the rough part of the hair tail. After applying the conditioner to the hair, when the hair is dry and forked seriously, wear a bathing cap to help absorb nutrients.
Dry your hair after washing?
After washing the hair, the hair scales are open. At this time, the hair is very fragile. Rub the hair hard, the hair scales will be damaged and the hair will become rough.
Suggestion: cover the hair with absorbent towel and absorb the moisture.
Air dry after washing?
Many people worry that hair dryer will damage their hair. In fact, when the hair is half wet and half dry, bacteria are more likely to grow.
Suggestion: after wiping with towel every time, blow dry with hair dryer, blow dry the short hair to over 90%, and blow dry the long hair to over 70%. (source: Popular Science China)
Source: Science and technology daily editor: Liu Yiyang
Reviewed by: crystal tube
Final: Leng Wensheng