Can Keratin Treatments Damage Hair

If I could describe my hair in one word it would be meh. I basically have a non-texture texture—it’s equal parts frizzy, dry, undefined, and if I’m being real, damaged (TY, years of heat styling!)—and it takes me a solid 40 minutes of blow-drying and flat-ironing to make it look somewhat presentable. And since I’m lazy as all hell, that usually happens, like, twice a month. Which means every other day, I pull my hair back into a messy bun and avoid the office bathroom mirror.

Whenever I complain to stylists about my hair woes, I usually get the same question: “Why the hell haven’t you tried a keratin treatment?!” Considering the hair-smoothing treatment (which claims to minimize frizz and flyaways, increase shine, and speed up styling) has been a go-to in the beauty world for years, I figured there was no harm in trying it out—especially if the end result could mean I might actually…like my hair? So not only did I go out and get one (spoiler), but I also found out everything you’ve ever wanted to know about keratin treatments, ahead.

What is a keratin treatment?

First things first: If you’re confused about what keratin treatments even are, welcome to the freakin’ club (see: me). Keratin treatments have become an umbrella term for any hair-smoothing process that softens curls and waves, minimizes frizz, and makes heat styling faster and easier for months. Basically, as long as keratin is one of the active ingredients in a hair treatment, salons can lump them all into the same “keratin treatment” category (including the Brazilian Blowout, Keratin Complex, Cezanne, and more). The issue? These formulas don’t affect hair in the same ways.

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Harsher treatments, like the popular Brazilian Blowout, are usually the preferred method if you’re after a smooth, super-straight look. Typically, these treatments contain formaldehyde (or more accurately, they contain chemicals like formalin or methylene glycol that release formaldehyde—which is a gas, fun fact—when they’re exposed to heat). Formaldehyde has gotten a bad rap in the hair world and for good reason: It can cause health risks for both you (and your stylist) with repeat exposure, so even though formaldehyde-based treatments keep your hair straighter longer, it isn’t recommended for regular use (definitely no more than four times per year).

Luckily, there’s been an uptick in gentle, formaldehyde-free alternatives in recent years, the most popular being Cezanne and Goldwell Kerasilk treatments, which contain ingredients like glycolic acid (an exfoliant that’s super popular in skincare products) and sericin (a component of silk). According to Kathy Combs, global director of Education at Cezanne, you shouldn’t expect stick-straight results with formaldehyde-free keratin treatments, since they’re more focused on softening and elongating your hair texture, rather than completely straightening it.

“Formaldehyde-free treatments smooth frizz without removing your texture,” says Combs. “That means your hair will retain its natural curl when you air-dry, but it can still look smooth and sleek with a quick blow-dry.” Keyword: quick, since as anyone with flyaways or frizz or thick, coarse hair knows well, heat styling can take a lotta time.

TL;DR: Keratin treatments with formaldehyde will usually straighten your hair, and those without it will smooth your hair. Still not sure which treatment is best for your hair? Neither was I when I booked my appointment at Nunzio Saviano Salon in New York City, which is why my stylist Alix Paige suggested we start with a consultation. After walking her through my ideal end results—I decided I wanted something super low-maintenance without losing any of my natural texture or body—we landed on the Cezanne treatment (again, a gentle, formaldehyde-free alternative).

How long do keratin treatments take?

Know that your keratin application totally depends on your stylist and treatment, but typically, you’ll need to carve out two to four hours for your appointment. Paige kicked off my Cezanne treatment with a quick shampoo and conditioner rinse, noting that it’s best to start with clean hair (translation: We needed to get rid of the layer of dry shampoo that was hiding in my roots). After rough-drying it, Paige painted the keratin formula over sections of my hair until my whole head was covered, then let it set for 30 minutes.

As soon as the timer went off, Paige gave my hair a quick rinse, leaving the majority of the treatment still on my strands. Next up? Heat, which activates the keratin. Paige first used a hair dryer to lock in the treatment, and then meticulously flat-ironed every single strand of hair on my head. The number of times your stylist will flat-iron each section depends on your end goals, but Paige decided to hit mine with a heavier hand (read: six to seven passes, versus the usual five) since I wanted super-smooth results.

When she finished flat-ironing my hair, I was free to go. The only caveat? My hair looked really, really, ridiculously straight—like, pretty much stuck to the sides of my face. She assured me, though, that I’d only have to deal with it for 24 hours (meaning, no tying it back or pushing it behind my ears), after which, I was cleared to wash it and style it however I wanted.

Are keratin treatments good for your hair?

There isn’t really a correct answer to this one, since the health of your hair depends on the formula your stylist uses. Generally speaking, you shouldn’t anticipate any long-lasting damage or side effects if your stylist is using a legit keratin treatment.

“Keratin treatments can be damaging if the hair is over-heated with a blow-dryer or flat iron during the process, so it’s important to make sure you see an experienced stylist who is cautious,” says Meri Kate O’Connor, hairstylist and colorist at Eva Scrivo in New York City, adding that those with color-treated hair should definitely begin with a consultation.

“All hair reacts differently, but smoothing treatments can sometimes lighten color-treated hair, leaving it a bit brassy,” she says. “It’s really on a case-by-case basis, though, so your stylist should be able to look at your hair and make a game plan.” Basically, almost anyone can get a keratin treatment, but always go for a consultation just to be sure first.

How long do keratin treatments last?

The way you care for your keratin treatment a hundred percent influences how long your results your results last, but on average, the effects should last for four-ish months. “The great thing about getting a keratin treatment is that it washes out of your hair—it doesn’t require a grow out,” says Paige. “That means you don’t need to worry about your roots coming in frizzy, and instead, you can focus on maintaining your treatment.”

Maintaining your keratin is super easy, BTW. After you leave the salon, make sure you pick up a sulfate-free shampoo, since harsh ingredients will strip your treatment every time you wash your hair (same goes for your styling products). Saltwater and chlorine don’t mesh well with keratin treatments either, but if you really can’t avoid them, Paige suggests rinsing your hair with cold water directly after you swim. “The better you take care of your keratin treatment, the longer it’s going to last,” she says, adding that some clients have seen results for as long as seven months with proper care.

How much do keratin treatments cost?

IMO, the only downside to getting a keratin treatment is that it can get pretty pricey. Costs vary from salon to salon and where you live, but typically, keratin treatments usually range from $250 to $500. Think of it this way though: If you’re someone who gets regular blowouts or spends hella time on their hair, the convenience you get with a keratin treatment is kinda, sorta worth it.

Keep in mind that there are plenty of hair-smoothing treatments that salons market for cheaper (some of which might work totally fine for your hair texture!), but if you’re after a true keratin formula, know that you likely won’t pay less than $200 (and if you are paying less, definitely call ahead and ask about the ingredients in the treatment, since you won’t be able to guarantee your results with an off-brand formula).

Can you air-dry your hair after a keratin treatment?

Yes, you totally can. Remember: Unless you go with a Brazilian Blowout, don’t expect your hair to dry stick straight without a little heat-tool action. If you air-dry hair that’s been treated with a Cezanne or Kerasilk formula, your natural texture will definitely still come through, but you’ll have way fewer flyaways and less frizz.

When I was finally ready to shampoo my hair (those 24 hours felt long), I was honestly pretty doubtful I would notice a big difference. But since I was looking for a sleeker, smoother result, I decided to skip the air-dry and instead blasted my roots and ends with a blow-dryer for five minutes. When I usually rough-dry my hair, I’m left with a fluffy, frizzy heap of hair that requires a lotttaaaa flat-ironing. So when I looked in the mirror and saw ridiculously smooth (and honestly, pretty damn straight) hair, I decided I was officially a keratin treatment convert.

That’s not to say my experience is by any means the norm, though, since your results really depend on your hair texture and your treatment. Cosmo senior beauty editor Chloe Metzger (hiii, Chloe) tested the Cezanne on her curly hair and noted that it barely loosened her texture. Since she very rarely heat-styles and only air-dries her hair, Chloe only noticed a difference in how silky and shiny her curls looked (which, IMO, still rocks but isn’t a game changer).

The Final Word

I am so freaking satisfied with my keratin treatment results that I would a hundred percent do it again. The fact that I can style my hair in five minutes flat has seriously changed my morning routine—I feel like I have a new hair texture, in all honesty. The only downside is the steep price tag, which I definitely don’t see myself being able to keep up with on a regular basis. When I do have some extra cash, though, I already know what I’m spending it on.

Ruby was the beauty editor at Cosmopolitan, where she covered beauty across print and digital. Her work has appeared on The Zoe Report, Fashionista, and StyleCaster. Follow her on Instagram.