Keratin Hair Treatments: What to Expect

New keratin-based treatments may save you hours each day.
WebMD Feature
Reviewed by Laura J. Martin, MD

When friends think of Susan Greene, a 38-year-old lawyer originally from Staten Island, N.Y., they instinctively picture her trademark kinky, curly hair.

And that is why they do a double-take when they see her today.

Like legions of women (and some men) who have spent decades struggling to get their curly, frizzy, or coarse hair to behave, Greene opted for keratin hair straightening, which is the latest trend in hair-straightening or relaxing.

There are a host of brand names available, including Keratin Complex Smoothing Therapy by Coppola, Global Keratin Complex, the La Brasiliana treatment, Brazilian Keratin Treatment, the Brazilian Blow Out, and Brazilian Hair Straightening.

“None of the ‘miracle treatments’ I have tried over the years lived up to their hype,” Greene says. “In my hours of Googling the treatments, I kept reading how it was life changing. So I went to the salon reluctant, but ready to pay a small fortune for what I hoped would not be another disappointment.”

She wasn’t disappointed. “I have the soft, wavy, silky hair that I have always dreamed of having,” Greene tells WebMD. “I make random people feel it and probably talk too much about how much I love my hair. ”

These Brazilian, keratin-based hair-straightening techniques are all the rage, but there are some concerns that certain formulations may contain high levels of formaldehyde, a known carcinogen.

Considering whether you should try keratin hair straightening for the first time, or for a follow-up treatment, despite all the stories in the media? Here are answers.

What Is Keratin Hair Straightening?

Most of today’s popular straighteners are keratin-based. Keratin is a protein found naturally in your hair. It can fill in gaps in the hair cuticle that are cracked, dry, or damaged. It is mixed with varying levels of formaldehyde, and applied to the hair, and then sealed in with the heat of a flat iron. The formaldehyde helps hold the keratin molecules together, which straightens your hair and keeps it that way.

The results of keratin-based treatments last about two to 2 1/2 months. Keratin treatments take about 90 minutes or longer, based on the length of your hair. The price also rises and falls with your hair’s length, but averages around $300.

Color — whether highlights, low lights, or merely covering up the gray — can be done on hair that has had keratin-based straightening treatments. In fact, some hair care experts recommend getting the treatment right after your color so that it seals the color in as well.


There is some downtime with these treatments — meaning not washing your hair for three or four days afterward, because the solution takes time to work, says hair stylist Henri Borday of New York’s Mizu salon and the corporate educator for hair care company Global Keratin.