A Formaldehyde-Free Keratin Treatment Transformed The Way I Do My Type 4 Hair

The first time someone mentioned a keratin treatment to me as an option for my type 4 hair, my mom furrowed her nose. “All that formaldehyde,” she tsked. That upturned nose and casual disgust stayed with me for years. Although multiple hairstylists suggested it could benefit my hair, I'd always be reminded of that moment. But after seeing results on friends, colleagues, and one very, very convincing hairstylist, I finally dove in and got my first keratin treatment last year. Afterward, I could do my hair without worrying it was going to look a whole mess. Blowdries were faster, straightening was easier, and I wasn’t losing entire days to wash day anymore — I could finally feel in control of my hair for the first time in a long time. 

However, reports of formaldehyde-releasing hair smoothing treatments causing concerns like hair loss and chemical burns, not to mention a possible link between lye in hair relaxers and breast cancer, were enough to give me pause and reconsider whether smooth hair is worth the potential risks. Then I began hearing about formaldehyde-free keratin treatment options and I was intrigued. Granted, formaldehyde-free keratin smoothing treatment brands like Cezanne, Kerasilk, and GK Hair have been around for a while. But are they as effective as the original formulas, which are still used in countless salons? If so, when might be the right time to make the switch?  

For years, keratin treatments and Brazilian blowouts have been marketed as heroes for those with frizzy hair. Not only are they effective at loosening kinks and coils, making the hair look smooth and shiny, but the results typically last for months, rather than days. The original formulations for keratin treatments included formaldehyde, which the International Agency for Research on Cancer recognizes as a human carcinogen. Keratin treatments are brushed onto the hair and "activated" using heat from either a blowdryer or a flat iron — sometimes both. The heat allows the treatment to penetrate the hair shaft, which creates a smoothing effect. However, if the treatment contains formaldehyde, it may prompt the release of formaldehyde gasses into the air. Formaldehyde in chemical hair straighteners has been linked to cases of endometrial, ovarian, and breast cancer. Not only that: According to the CDC, some immediate side effects of formaldehyde include a sore throat, coughing, chest pain, and eye irritation, while chronic issues have included migraines and asthma. 

New York-based hairstylist Kristen Glynn of the Scott J. Aveda Salon, tells R29: “In the past, I have used Keratin treatments containing formaldehyde, and I never felt great after — the masks we would use were not made for chemical fumes.” Glynn eventually stopped doing keratin treatments after she reported that colleagues were having adverse health reactions such as nosebleeds and lesions on their skin.

Cut to October 2023, and news broke that the U.S. Food and Drug Administration (FDA) proposed banning hair-straightening products that contain or emit formaldehyde. And not only formaldehyde but also “formaldehyde-free” straightening products that include methylene glycol, which, when combined with air, turns into a formaldehyde gas. This was a result of years of petitioning by the Environmental Working Group and it’s a big move to make beauty products safer for everyone. (About time.) 

It’s winter in New York, which means my hair is out and ready to be silk-pressed any day of the week. I was looking for a smoothing treatment to make my hair manageable enough that I felt confident doing it myself (even though attempts have gone  very south in the past.) For this reason, I was thrilled to test out the Cezanne Smoothing Treatment with Glynn. 

The treatment promises to reduce frizz and deliver smoother and stronger hair that lasts for months. The brand says that it has never used formaldehyde in any of its products. Instead, it enlists a proprietary formulation made up of keratin (the protein that makes up your hair), glyoxyloyl carbocysteine (which reduces static) botanical extracts, vitamins, and sericin, which is a component of silk. “In silk, sericin acts as cement between fibrous filaments,” which maintain the structure of cells, explains Kathy Combs, vice president of global education for Cezanne Professional Products. “It acts similarly when Cezanne is applied to the hair, bonding to natural keratin and cementing itself between strands of keratin proteins — sealing in moisture, adding luster, protecting bonds, and locking hair into a smoother, straighter form,” says Combs. This formulation is intended to help replace and repair lost and damaged protein mass by using a low-pH system to open the cuticle and infuse the cortex with that blend. Then, when heat is applied, it causes the cuticle to close and the ingredients are “locked” into the hair, smoothing the hair from the inside out.

I sat down in the salon chair while Glynn looked over my hair and walked me through the steps. First came deep detoxifying shampoo to make sure there was absolutely nothing on my scalp or hair, followed by a rough blowdry, wherein I emerged my best Mufasa. She then applied the product to my dry hair in sections of four before I sat for 30 minutes while it set in. Having a lifetime of experience with relaxers, I’m always a little wary when it comes to chemicals sitting on my head for a long period, but this was both stink- and tingle-free, a true joy. Next, she rinsed the treatment and blowdried it again, before flat-ironing my hair straight.

The results were amazing — my hair was shiny, soft, and didn’t feel sticky or filmy, which was a problem I had after my last keratin treatment.

But the real test was my hair vs. a Brooklyn radiator-heated apartment. There was no control over the heat in my place, and I was also cooking. This is typically a dangerous combination any time I’ve just had my hair done. Do you remember the scene in Legally Blonde where Elle Woods uses her knowledge of perms to win her case? Any kind of moisture combined with a chemical treatment can result in the work being undone and reverting to its original state. But nope, not a single inch of reversion for someone who had previously had their hair done the week prior only for it to completely revert within four hours. While my hair isn’t as bone-straight as a Japanese straightening treatment would provide, my roots aren’t puffy and the texture is looser, but the curls are still curling. This was everything I’d asked for. Another key note is that I pulled my hair back in a claw clip before remembering the rule that I could not, by any means, put it back because it would take on the shape it had been manipulated into. This is the opposite of what you want with a chemical straightening treatment. Glynn reassured me that I had nothing to worry about: “Maintaining your Cezanne is easy: There is no downtime. You can wash that day if you want, put it up, put clips in it, swim, anything.” Her main suggestion for maintaining the results is to use a sulfate-free shampoo and conditioner to make the results last longer, which I typically do anyway.

"Keratin treatments, as we know them, are on their way out, and out of personal experience, I can say that plenty of alternatives fall short. Cezanne isn’t perfect — it’s not cheaper than a traditional keratin treatment, nor is it an option for vegans. But Cezanne’s keratin treatment gives frizz-free, smooth results without the danger, making it a great choice for anyone looking for a safer way to get smooth and shiny hair.