What is a Keratin (Or, "Brazilian") Hair Treatment?

Find out how they work, how safe they are, the formaldehyde factor & more

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Keratin hair treatments (also known as Brazilian hair treatments) smooth out and straighten wavy or curly hair. They're super popular across the country, but these treatments, which rely on formaldehyde (a known carcinogen when inhaled), are also very controversial.

Find out if keratin hair straightening treatments are safe, if you're a candidate, how much they cost, how long they last and what happens when you get one in this article.

How a Keratin Treatment Works

Basically, a stylist will apply a keratin product to your hair (there are many versions available to salons some containing more formaldehyde than others, more on that below) carefully avoiding getting the product on your scalp. The treatment remains in the hair as it's blow-dried and then flat-ironed. Some stylists wear masks as they do the treatment and they may have you wear one, too. Treatments are usually done near an open window with a fan blowing.

The treatments usually take 2 hours or longer depending on the length and thickness of your hair. You should not wash hair for 3-4 days.

Am I a Candidate?

Unlike some hair straightening treatments, Keratin treatments can be done on color-treated hair. They work well on people (men get them, too) with wavy to tight curly hair. If you are sick of fighting the frizz, you'll love the results from the keratin treatments -- they get rid of frizz even in humid or rainy weather.

How Much Do They Cost and How Long Do They Last?

Cost varies from city to city and depends on the poshness of the salon (high-end salons charge more), but they typically range from $300-$800.

The treatment lasts usually about 2 months or a bit longer. And don't expect the pin-straight hair you get with the Japanese treatment.

You'll have to blow-dry or flat-iron hair to get it to be straight, or you can let your hair air dry into soft waves. But your blow drying time will be cut down by about 40-60% thanks to this treatment.

How Do I Maintain My New Hairstyle?

Experts recommend you don't wash hair for 3-4 days after treatment. Shampoo with a sulfate-free shampoo. I include a list of great shampoos in Best Sulfate-free Shampoos. 

What's the Difference Between a Keratin Treatment and Brazilian Hair Straightening?

Back in the early 2000s, a buzz began generating around New York City about Brazilian hair straightening. It was the hot new thing from Brazil and women with curly hair were loving it even more than the more permanent Japanese hair straightening treatments because the Brazilian promised glossy, sleek hair that maintained some of its volume. Plus, it worked on color-treated hair and lasted 2-3 months. The Japanese treatments left you with stick-straight hair for about 6 months until your own curly hair grew back in. 

For a couple years, Brazilian treatments were the treatments to get if you had wavy or curly hair that you wanted to smooth out or straighten. Popular brands included Brazilian Keratin Treatment, the Brazilian Blowout, Brazilian Hair Straightening.

The word "Brazilian" (not to be confused with the Brazilian bikini wax, which happens further down the body) was the term that sold it.

And then the word got out that the amounts of formaldehyde in these popular Brazilian treatments were so high, it was dangerous -- especially to the beauticians applying the solution and then flat-ironing the hair (formaldehyde is most dangerous when released into the air).

So what happened? Brands changed their marketing tactics. Instead of plugging the "Brazilian" bit, they started plugging the keratin bit. Because, after all, these treatments all contain a lot of keratin, a natural protein found in hair. Off their pages went any wording about formaldehyde. They got away with it because no one is regulating or enforcing these treatments in the US.

So, Are Keratin Treatments Safe?

This question is up for debate.

I know many women in New York City who get these treatments a couple times a year and have had no known issues. They feel the results are well worth the risk.

If you do opt to try a treatment, I recommend getting your hair done by someone who specializes in keratin treatments. If your stylist uses a flat iron that's too hot, for example, she or he could damage your hair. And you want someone who knows exactly what's in the product the salon uses. 

The danger in these treatments is not the protein keratin, which actually strengthens your hair shaft and makes your hair more resilient to breakage, it's the formaldehyde, which is a known carcinogen that can cause health problems when inhaled.

Studies show that some keratin brands market themselves as "formaldehyde-free," which is almost always bogus. For a keratin treatment to work, some formaldehyde will be in the product. How much is what matters. An honest stylist (or one who knows what he or she is doing) will know how much formaldehyde is in the treatment used on you. For more information on this, see the Environmental Working Group's in-depth study on brands that hide formaldehyde.

Experts are in agreement that the main danger is not to those getting the treatment, but to those giving the treatment. Some beauticians work with potentially poisonous gasses several times a week. What effects the formaldehyde will have on them is still unknown.

More on hair straightening treatments:

  • Japanese Hair Straightening Treatments
  • How to Give Yourself a Straight Perm