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Brazilian and Japanese Hair Straightening - The Dangers

Brazilian and Japanese Hair Straightening
August 5, 2012 Reviewed by admin 29 Comments

Silky smooth hair has been sought after for years, so it's no surprise that people from Japan and Brazil have come up with their own ways to more permanently iron out frizzy tresses. Brazilian hair straightening treatments and Japanese hair straightening treatments have become popular recently, but when it comes to hair straightening and relaxing, what is effective and safe?

Japanese hair straighteners are permanent. In fact, they work on breaking and rearranging the internal bonds of hair so that when the process is complete, your hair is permanently straightened out. A chemical by the name of thioglycolate is usually used for this thermal process; it will break the cystine proteins which are present in the cortex layer of the hair shaft. Once those are broken down, hair can be any desired shape.

However, this also means that the new growth will be your original curly hair, and that growing out process will be a lot like having to upkeep highlights. A head of half-curly half-stick straight hair doesn't sound very appealing. Plus, this process could be damaging if the chemicals are left on too long, and that damage to hair is irreversible. Many say that after several Japanese hair straightening treatments the luster of your hair is affected, too.

The Brazilian hair straightening treatment alternative has been controversial for its own set of reasons. Though the Brazilian straightening process requires an application of active keratin, a protein found in the top layer of our skin and hair that makes it strong, it is often used in conjunction with formaldehyde for semi-permanent straightening results. The Brazilian hair straightening treatment formula is sealed into the hair using heat. Some experts say it is likely that the formaldehyde chemicals break hair's disulfide bonds and change its shape. And in the UK, the Cosmetics, Toiletries and Perfume Association recently reported that some products contain up to 10% formaldehyde (the limit under the UK Cosmetic Products Safety Regulations is only 0.2%), meaning some Brazilian hair straightening treatments are using dangerous levels of these chemicals.

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Formaldehyde is scary, to say the least; it is on the Department of Health and Human Services' "reasonably anticipated to be human carcinogens" list, and has been linked to cancers like leukemia. The Cosmetic Ingredient Review (CIR) Expert Panel does list formaldehyde as "safe as used" in cosmetics within certain specifications from research done in 1984, but these specifications include using it in quantities of less than 0.2 percent. An investigative article in Allure from 2007 tested three salon samples of individual Brazilian hair straightening solutions, only to find that all three of the formaldehyde levels were in excess of the recommended .2 percent limit.

According to one study in a 2010 Toxicology Science Journal, inhaled formaldehyde is classified as a known human and animal carcinogen, causing nasopharyngea cancer. Brazilian hair straighteners are applied to the hair and heated with a flat iron, vaporizing the formaldehyde and releasing it into the air. According to the Professional Beauty Association, both stylists and clients can be exposed to levels of formaldehyde greater than 0.75 ppm by inhaling these vapors. Another study showed that the chemical in Brazilian hair straightening treatments has mutagenic risks. Doesn't that seem to be too toxic of an occupational hazard to mess with?

There are some formaldehyde-free options, though, which range from completely hyde-free, to moderate levels of organic aldehydes. Among them is Brocato's Curlinterrupted Keratin Smoothing System which claims to be a formaldehyde-free, thio-free, sodium hydroxide-free, keratin-based hair straightening solution.

But some argue that formaldehyde-free doesn't equate to completely safe either. Cosmetic chemist Ron Robinson of says aldehyde is from the same family of organic compounds. Aldehyde and formalin are derivatives or chemicals in the same family, which means they still produce similar noxious gases and require the use of face masks and ventilation during processing. Common "formaldehyde-free" products also often contain glutaraldehyde, biformal (oxalaldehyde) and ammonium thioglycolate. None of these chemicals are squeaky clean.

In the fight against frizzy curls, Brazilian hair straightening does seem to be an appealing method on the surface. But given the high risk involved, it is a little too toxic to ignore the dangers.

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  • March 4, 2018

    by Cristina

    I would like to know some hair straighteners where I can get a list of some hair straighteners composed by thioglycolate and keratin, please?

  • November 25, 2017

    by Javier

    I just read your article about formaldehyde in hair products and I like to comment to you : I have worked in the development of cosmetics for many years. The issue of hair straightening and restoration has gone from being a fashion to a necessity in my country and in many others. That's why "Keratin" is very popular, products with formaldehyde despite its drawbacks are still widely used. As in our company we manufacture these products based on glyoxylic acid, we buy formaldehyde detectors in the air, to show that the competition uses formaldehyde. Our surprise was a day that by mere chance we put the detector near the hair to a woman who had been treated with formaldehyde, three weeks before and the detector indicated high amounts of gas near the hair. If the hair is moistened the result is much worse. This means that people and their very close, breathe for several weeks, undesirable amounts of gas. I hope this information is of your interest.

  • July 13, 2017

    by Lisa

    Question: can Japanese hair straightening cause hair follicles to thin and cause pattern patches of bald spots to the hair. Your response will be greatly appreciated

  • October 11, 2014

    by Andrea

    Hi well I stay in kimberley and I want to get the Yuko Liscio Japanese straighter for my hair I want to do it by a professional. I hair it helps hair grow and if you have thick hair and don't dry it with a blow drier you hair comes out straight I need it and only Cape Town I don't know which salon

  • March 20, 2013

    by kim

    hello everyone

    I'm from cape town and I am thinking about getting the Japanese treament but I have soft hair(feather)dry as well...can I still do it? Can anyone recommend me a good salon in Cape Town.

  • February 4, 2013

    by Danielle

    I am a stylist! If your going to permently straighten your hair always always always get
    . It professionally done! I cannot tell you how much a difference it makes! If you do it yourself and mess up and go into a salon it is so difficult to fixhete vproblem because we were not there to see what you did.

  • January 23, 2013

    by JustD

    A great article, thank you Summar! I've heard about the Brazilion issues with the Brazilian hair straightening methods and I decided to forego it even though the adds make the hair look amazing. I like breathing.

    Also, I've got salt'n pepper curly locks which dries into curly frizzies in the humid summer months where I live. My one alternative to beating these frizzies is winter problem at all then, just doesn't last long enough in Houston.

    Additionally, I have used Wen Sweet Almond Mint Cleansing Conditioner years ago and it really worked for me, I just got tired of the huge bill attached to it. I now use 2 leave-in conditioners that I get from Folica and they work amazingly well for me and a little goes a long way, Keratin Complex Infusion and Crack (LOL, real name) Leave-In Hair Cream. No, they are not organic, but they help keep my hair from frizzing up like crazy and leave me with manageable tresses instead. I get more compliments than I know what to do with, I'm lying, I know what to do with them ;D Sharing in case anyone is interested.

  • January 23, 2013

    by Mariska

    @Prianca, you just need to look around. If you are in Cape Town, there are actually quite enough salons that do this :) Let me know where you are at.

  • January 17, 2013

    by allen

    Hi Prianca, where did you get your straightening in Hong Kong? I have been looking for months to get Yuko hair straightening done but no luck. please let me know.


  • January 5, 2013

    by leigh

    hi there

    Thank you for your valuble info , just want to answer Prianca that the salon in Cape town on the V&A Waterfront is called Frank Fouden does those Japenes Straightners....
    Hope it helps. Thanx GBU

  • November 14, 2012

    by Prianca

    I had a Japanese permanent straightener done in Hong Kong and it was the best of my life, from dry. frizzy hair, curly and well, just repugnant hair, I had the straightest silkiest hair. Although your natural hair does grow back from the roots, this is worth it ! ! No need for the salon. It has been a year now and I'm looking for a place to get this done in South Africa :( I'm out of luck.

  • August 8, 2012

    by Sixtgy

    Has any had the Bio ionic thermal hair straightener? This hair straightener contains thioglycolate as a chemical. Is this chemical harmful any more harmful to your hair or body as a perm? I am a woman of color and have 4b hair. I have went on line and asked salons about this hair straightener by the name of Japanese, Bio Ionic and all the salons state it is a by- product of keratin hair straightener. I live in St. Louis, Mo and no one her use the Japanese or Bio Ionic Thermal

  • June 21, 2012

    by Danielle

    I used the Brazilian hair straightener for years. I never heard that it had formaldehyde in it until after the fact that I was diagnosed with stage 2 lung cancer. I know for sure that this was a very large part why I got lung cancer. There is NO doubt in my mind. I was 38 years old when I found out. I am now 40 and had my cancer surgically removed. The doctor told my that my "Lungs where full of soot". PS I do NOT smoke.

  • March 29, 2012

    by Abs

    So what do you recommend for someone who has coarse, thick curly hair. Are there any options?

    Is dimethicone safe in a hair straightener?

  • March 21, 2012

    by Kati

    I'm not sure about the japanese but
    that is the MSDS for the brazilian blow out. When I worked in a restaurant an MSDS was only required for harmful chemicals. This procedure is not good for you OR your hair.

  • February 20, 2012

    by Babs B

    Hey ! I use this hair straightening technique - look at #3 "Blow Dry Techniques" -

    I followed the steps exactly 6 months ago and OMG - its my favorite technique now and gets my hair so STRAIGHT! Try it...

  • February 14, 2012

    by Patty

    I have been using the Japanese Straightening Method for the past 3 years and my hair is just as thick and shiny as ever before. I don't have to use any heating products (blow dryer, straightener, etc) because I can just wash my hair and go. I am going in for a touch up tomorrow because it has been 8 months and my curly hair is starting to affect the style. It is not super curly on top and stick straight below. It is just starting to come in slightly thicker but the weight of my long hair pulls out the curl. It is not noticeable but I am going in but my bangs are slightly more "puffy" looking. I recommend this procedure to everyone!

  • December 19, 2011

    by Cindy

    You have not stated any factual evidence on the downside of Japanese hair straightening in your article. What you did write, seemed to be anecdotal at best, but nothing convincing about negative health effects. I have had this procedure performed on my hair over the past ten years at least nine or ten different times in over three different countries between North America and Asia. My hair did not lose its lustre as you stated; in fact, it becomes even more shiny and silky.
    As for the 'half-curly, half stick-straight hair' comment, that can easily be remedied with periodic touch-ups with a qualified hair technician. Regardless, that has nothing to do with any 'danger' of which you write.

  • May 25, 2011

    by Luci


    The problem isn't just the fumes that the client is exposed to during the treatment. A huge factor is that they will go home and use heating treatments (blow-dryer, straightener, curling iron) every day (or near every day), and that will release the chemicals again into the air. I had this treatment done a year ago, and while I had fairly good results, I could smell the horrible chemical smell every time I used heat on my hair. Then all the research started to come out and I understood why. I called my stylist and the brand she used (called Inoar) isn't supposed to have high levels of formaldahyde (which is also why the results weren't as drastic and impressive), but I could smell that chemical for weeks and weeks after, and it was really strong. I decided it wasn't worth the risk for me.

  • April 17, 2011

    by Karen

    i have my hair "japanese straight", honestly I cant say enough good things about it. The product my stylist used on my hair is formaldahyde free and one of the best products used on the market, though I forget the name of it at the moment.

    I got it done 2 months ago and it still looks just as straight & beautiful as the day I got it done. Its silky smooth, not dry at all.

    On a scale of 1 to 10 (1 being straight as an arrow & 10 being major frizzy afro) my hair was about a 7, now its easily a 1. I can curl it, I can crimp it, I can do anything I want with it.

    Im extremely satisfied, but I also did my research before deciding on a stylist to let do my hair. I called around, asked how long the ppl had been doing the treatment, and how often they do them.

  • March 1, 2011

    by Sara Thomas

    WOW! SUPER INFORMATIVE!! I've been doing hair for 17 years,my true love lyes with color, but all the hype on this BB treatment I'm ready to hop on th band wagon! But didn't realize how truly dangerous it can be.THANX FOR VALUABLE INFO!!!! If both client and stylist wear a it safe?

  • November 18, 2010

    by Christine

    The media has seriously scared people over keritan hair treatments. Our salon had our air tested by a professional company while 3 treatments were being done. We have high ceilings with numerous ceiling fans on and have our doors open while they are being done. Our air quality was very safe. Its all about airflow and good ventalation. You wouldn't paint in an room or use some cleaning supplies in a room without good ventelation. It can be done quite safely! What kertian can do for someone whos hair gets frizzy curly or unruly in anyway is amazing! People love it and it doesnt damage the hair!

  • October 3, 2010

    by Me

    Lots of people have dry hair. I honestly don't think Jennifer Aniston's straightened hair looks truly "silky" or like naturally straight hair. I would rather use the Japanese straightening method and have dryish (not too dry) straight hair, than take a chance with my life with the Brazilian treatment. Which is worse, taking a chance at some hair damage, or at damaging your lungs and possibly shortening your life? (this should be a no-brainer, which is why I still to this day don't understand why many ppl still choose the latter choice....)

  • August 18, 2010

    by Jordana Lorraine, Brazilian Blowout Specialist in Los Angeles

    BRAZILIAN BLOWOUT is a brand name, often copied or falsely advertised. The REAL BB is formaldehyde-free and works wonders without damage or permanent changes in your hair.

  • August 9, 2010

    by Summar

    I just heard back from Brocato in regards to their ingredients, and here is what they said:

    "Thank you for your enquiry , our is system is 100% formaldehyde free. We have a two part system , a very gentle gel is applied to the hair that softens the bonds in the hair, the key ingredient is ammonium bisulphate.

    Second part of the procedure a keratin spray is applied and then dried into the hair, finally you finish with an iron and an active serum."

    I looked into ammonium bisulphate and it is used as a no-lye hair relaxer. But it also selectively reduces the cystine bonds, so it is weaker and works more slowly. Also, while it's weaker formula is less inclined to irritate, there is a case of contact dermatitis after using it as part of a hair relaxing treatment. Close, but no cigar.

  • August 6, 2010

    by Ines

    I agree with Matie, brazilian keratin treatments left my hair smooth ,shiny and even have repaired some of my split ends. My hair is healthier than ever. I agree, it all depends on the product. I prefer not to take my chances and have it done professionaly every 6 months (I cant afford to have it every 4 as recommended) Pricey but worth every penny.

  • August 5, 2010

    by matie

    That depends on the brand, so far my experience with keratin treatments have been anything but bad.

    For example, Taip and Maxliss keratin have great products available in order to get the best results, aside from their keratin hair treatment.

    And they are giving away 60ml samples for $20, if you want to go the safe way for a strand test:

    Good luck!


  • August 5, 2010

    by Julie Kay

    My best friend, after two years of yearning-yet-doubt, had her hair "straightened via the Koreon method (probably the Japanese method). It didn't take on her hair, but the process still took 4 hours, and when complete, she had the dryest hair of her life. She knew it was deeply damaged. She's now working to restore hydration etc. This article is timely! Thank you, Summar. ~jk

  • August 5, 2010

    by Jaysie

    Summar - Thank you so much for the information on keratin treatments for frizzy hair. You saved me so much time as I was about to start researching the latest facts on these products. It's been so humid this year that I can't get control of my frizz and I've been pushed to the edge of doing something drastic, but now I've put on the brakes. I think I'll read up on the Brocato product though.

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