Skip to content
Home » How Does A Keratin Treatment Affect Your Hair?

How Does A Keratin Treatment Affect Your Hair?

We dug deep into the science of volumizing hair products, learnt about the history and chemistry of antiperspirants, and studied Accutane. We’re now discussing keratin treatments. The hours-long, in-salon treatment de-frizzes and de-puffs the hair, but how does it work? What can keratin do for your hair? Is it appropriate for all hair types?

Needless to say, we still have some unanswered questions. We spoke with the Keratin Complex team as well as hair industry professionals, including Jerome Lordet, head stylist at Pierre Michel Salon, and Annagjid “Kee” Taylor, celebrity hair stylist and author of All Hair Is Good Hair, to get some answers. Continue reading to find out all you need to know about receiving a keratin hair treatment.

What is Keratin?

Keratin is a protein present naturally in our hair, skin, and nails that helps to keep them strong and healthy while avoiding breakage.

Are Keratin Treatments Dangerous?

Both Vaccaro and Saviano warn against keratin treatments that contain formaldehyde, the chemical that keeps hair frizz-free and straight for months at a time. Formaldehyde is a colorless, pungent-smelling gas, according to the Centers for Disease Control and Prevention (CDC).

The United States Environmental Protection Agency designated it as a chemical that might cause cancer with continuous exposure in 1987.

Saviano recommends looking for reputed salons that provide formaldehyde keratin treatments at a safe percentage (anything less than 0.002% is OK) or salons that provide keratin treatments using formaldehyde substitutes.

You may be interested in: Keratin For Hair: What Is It & How To Use It?

What Exactly is a Keratin Treatment?

Keratin is a fibrous protein found naturally in hair that functions as a humidity-protective layer (the primary cause of frizz). The sun, environment, style, and chemical treatments cause the hair to lose keratin with time, resulting in the formation of porous areas (much like potholes in a road). “Keratin works with the porosity of the hair on its own.

Most frizz, damage, and tangles are caused by porous hair “says Abraham Sprinkle, a member of the Keratin Complex International design team. “Keratin treatments fill in the spaces where keratin has been lost, preventing humidity and giving hair a healthier appearance. Consider how spackle handles nail holes in sheetrock: the surface is left smooth.”

There are several keratin treatments to select from, the most popular of which is the Brazilian blowout (in which the hair texture is straightened out). “A keratin treatment is more for smoothing and frizz management than a straightening treatment, which is used to straighten the hair,” Lordet adds.

“While the keratin treatment may somewhat straighten the hair, it retains more body than a straightening treatment.”

Sprinkle concurs, adding “Unlike straightening treatments, which can disrupt protein links to remodel hair structure into a permanently straight shape, Keratin Complex treatments eliminate frizz and restore health to deliver the straightening, smoothing look without permanently affecting the structure. This gives you the option of styling it wavy or straight as desired.”

Let’s check: Best Keratine Treatment For Your Hair In 2023

This strong treatment, performed in-salon by a trained stylist, replenishes the hair with high concentrations of keratin that permeate throughout the hair structure and are sealed within the cortex to heal the damage. Sprinkle adds, “This seals out humidity, heals damage and breakage, and rebuilds strength to create smoother, shinier, and healthier-looking hair, boosting manageability and greatly decreasing styling time.”

A keratin hair treatment can cost anywhere from $300 to $600 each session, depending on where you go. (For comparison, a single treatment at Pierre Michel Salon costs $450.)


Keratin Treatment Advantages

  • Blow-drying time can be decreased in half.
  • In humid conditions, prevent frizz.
  • Smoothes the cuticle of the hair
  • Hair is less prone to tangling.
  • Gives a glossy sheen

A keratin hair treatment, according to Taylor, is ideal for persons with frizzy hair and is a healthier alternative to conventional straightening procedures (such as relaxers). “Keratin treatments fully smooth out your hair and keep it free of frizz since they fill up the porous spaces in your hair strands,” she explains.

“One of the primary advantages of a keratin treatment is that it smooths out your curl pattern. If you frequently massage your hair, this will save you a lot of time.” Those with naturally curly hair often don’t perceive shine in their hair (curls reflect light less than straight hair)-after a keratin treatment, your hair will seem much shinier.

How Do I Get Ready for a Keratin Treatment?

A keratin hair treatment, like any other chemical process for the hair, should be performed by a professional, and any necessary preparation should always be discussed with them. However, Lordet warns against dyeing your hair before to treatment since the chemical might remove the color and change it.

Finally, check sure you are not allergic to formaldehyde, as it can cause stinging, itching, and burning eyes, nose and throat discomfort, and a runny nose in individuals who are sensitive to it. (As a side note, keratin treatments are not suggested for pregnant women.)

Lordet recommends against keratin treatments if you have fine, straight hair since they may make it look flat and lifeless.

What Can You Expect From a Keratin Treatment?

“A technician will cleanse your hair twice with clarifying shampoo to ensure it is thoroughly clean, free of buildup or residue, and ready to absorb all of the product,” Lordet adds. “The keratin solution is then applied to damp hair and brushed through.

(Note: the solution may cause itching on the scalp.)

“The time it takes for a keratin treatment varies on the formula used, as well as your hair structure and hair volume—Taylor says it usually takes two to four hours.

Finally, the hair form is modified with heat—first with a blow-dryer, then with a flat iron—to seal in the treatment and create a humidity-resistant finish and smooth, silky strands.


“Avoid washing hair shortly after the treatment to enable the product to soak in,” Lordet advises. To avoid denting, avoid handling it or putting it up for three days after treatment. Taylor continues, “If you don’t take care of the treatment afterward, it will do more harm than good to your hair. Keratin treatments, owing of the intense heat and chemicals involved, can cause hair loss and increased shedding if not properly cared for.”

Adverse Effects of Keratin Treatment

While keratin treatments do not harm the hair, using a flat iron at a high temperature can. When determining the temperature, always use a professional titanium flat iron and professional judgment—start at the lowest specified temperature and raise only if required.

“Keratin treatments can last up to six months, but you may notice that it permanently changes your curl pattern,” Taylor explains. “You must use sodium chloride-free hair products to keep your results. Wrap your hair in a silk or satin scarf (or pillowcase) to retain in moisture, as the treatment might cause your hair to dry out faster.”

Lordet adds that not washing it too frequently might help it last longer (over time, this can wash the keratin out). “I advocate using a natural dry shampoo in between washes—the Cleo & Coco Dry Shampoo + Body Powder ($16) is fantastic for adding body and refreshing the hair,” he adds.

Keratin Treatments: Can They Cause Allergic Reactions or Respiratory Issues?

Keratin treatments, sometimes known as the six-month blowout, are currently a hotly disputed issue. They were quite popular at first because they worked. “Keratin treatments are used to keep some of the curls and get rid of frizz,” explains hairdresser Nunzio Saviano. However, after learning that these treatments involve hazardous substances, individuals have been skeptical about whether they are worthwhile.

We questioned Saviano and Glamsquad Creative Director Giovanni Vaccaro for their thoughts on the hazards of keratin treatments and whether we should stop using them altogether. Fortunately for those keratin-treatment devotees, the answer was no. “I wouldn’t say [keratin treatments] are always detrimental for your hair,” Vaccaro explains.

“There are several kinds of keratin, and it’s vital to understand which one you’re using and how frequently you get it done.” We had them explain it out for us in further detail.Read on to learn about the harmful affects keratin treatments can have on your hair and how to avoid them.

The CDC mentions typical formaldehyde adverse effects such as sore throat, nasal bleeds, and irritated eyes.

“For years, stylists have claimed that using these hair treatments caused difficulties breathing, eye discomfort, and nosebleeds,” Tina Sigurdson, EWG associate general counsel, stated in a press statement announcing the complaint.

“At least since 2008, the FDA has been aware of the health risks linked with the goods.” However, it’s important to note that these difficulties have largely been documented among stylists; salon consumers seldom have such significant responses, unless they have an allergy.

Is there a risk of hair breakage and increased formaldehyde exposure when using Keratin?

When obtaining a treatment, Saviano recommends paying attention to how much heat is administered to the hair.

“If they use too much heat or over-straighten your hair, it will dry out faster than normal and cause breakage,” he explains. This is caused by the hairdresser either choosing a temperature setting that is too high for your hair type or repeatedly moving the iron over your hair.

The temperature at which your stylist flat irons your hair will be determined by several factors, including your hair structure, the amount of curl reduction you want, and whether or not your hair is color treated. Someone with finer, straighter hair will require far less heat than someone with thick, wavy or coily hair. Make careful to choose a hairdresser who is skilled at administering keratin treatments to hair of your exact texture and demands.

“If you have previous damage to your strands, the high temperature of the flatiron to lock the chemical into the hair is hazardous,” adds Vaccaro. “On top of that, when heat is applied to the hair, formaldehyde is released into the air, which individuals around inhale.” If you’re receiving a keratin treatment that involves formaldehyde, make sure you go to a well-ventilated clinic.

The Bottom Line

As previously stated, formaldehyde alternatives are now available in several keratin treatments. These have the same silky texture as the others, but the hair is held in place by glyoxylic acid. 5 Inquire with your stylist about formaldehyde-free products such as Goldwell Kerasilk or Trissola Solo.

Keratin Complex is another salon alternative. The brand provides several solutions, ranging from a traditional smoothing treatment to one for sensitive hair. These are intended to restore damaged hair rather than straighten it. Still, that might help you tame your frizz without the cost or hazards of straightening.

You can make better selections regarding keratin treatments now that you know everything there is to know about them. According to Saviano, if you go to respected salons and do your research on the products they use, you should be alright.

“Always consider the kind and structure of your hair [as well as] your daily maintenance (other chemicals you are currently using—color, single process, and so on),” Vaccaro advises. “Make sure you speak properly with your stylist.”