A keratin treatment, sometimes called a Brazilian blowout or Brazilian keratin treatment, is a chemical procedure usually done in a salon that can make hair look straighter for as long as 6 months. It adds intense glossy shine to hair and can reduce frizz.

The process involves getting your hair washed, then having a stylist brush the treatment onto wet hair where it will sit for about 30 minutes.

Some hair stylists prefer to blow dry the hair first and apply the treatment to dry hair. They’ll then flat iron the hair in small sections to seal in the treatment.

The whole process can take several hours — so bring a book or something quiet to do!

If you’re not sure if keratin treatment is right for you, weigh the pros and cons below.

The body naturally makes the protein keratin — it’s what hair and nails are made up of.

The keratin in these treatments may be derived from wool, feathers, or horns. Certain shampoos and conditioners contain keratin, but you’ll typically get the greatest benefits from a salon treatment done by a professional.

Benefits of getting a professional keratin treatment or doing one at home can include:

Smooth, shiny hair

Keratin smooths cells that overlap to form hair strands, which means more manageable hair and less frizz. This makes for hair that dries with little frizz and has a glossy, healthy look to it.

Keratin can also reduce the look of split ends by temporarily bonding the hair back together.

Long-lasting results

As long as you care for a keratin treatment by not washing your hair too frequently (2 to 3 times a week is enough), then your keratin treatment can last up to 6 months.

More manageable hair

Keratin treatments make hair more manageable, especially if your hair is particularly frizzy or thick.

If you constantly heat style your hair, you’ll notice that with a keratin treatment your hair dries more quickly. Some people estimate that keratin cuts their drying time by more than half.

Your hair may also become healthier and stronger since you can air dry it more often, saving it from heat damage.

Hair growth

Keratin can strengthen and fortify hair so it doesn’t easily break off. This can make hair seem to grow faster because the ends aren’t breaking off.

Formaldehyde

Many (but not all) keratin treatments contain formaldehyde, which can be dangerous if inhaled.

Formaldehyde is what actually makes the hair look straighter.

According to an Environmental Working Group investigation, some companies will actually try to hide the fact that their keratin product contains the chemical.

Alternatives to formaldehyde

More permanent straightening options like relaxers (sometimes called Japanese straightening) actually break hair bonds using the ingredients ammonium thioglycolate and sodium hydroxide. This makes for permanent results, but can also cause an awkward growing out phase with non-treated hair growing in curly at the roots. There are keratin treatments that are formaldehyde-free (they use glyoxylic acid instead) but they’re not quite as effective.

Healthline

Cost

Each treatment can range anywhere from $300–$800, plus tip. There are less expensive at-home options available, but the results will not last as long.

Make the most of the cost

Keratin treatments shouldn’t be done more than three times a year, as over time they can start to damage hair. Summer, when frizz is more pronounced because of humidity, is generally when people want to get them done.

Healthline

Hard to maintain

Washing your hair less and avoiding swimming might make it harder to maintain for some people.

  • The type of water on your hair matters. Swimming in chlorinated or salt water (basically a pool or an ocean) can shorten the life of your keratin treatment. You’ll also need to invest in shampoo and conditioner that are free of sodium chloride and sulfates, as these can both strip the treatments.
  • Wait to wash. You’ll have to wait 3 to 4 days post-keratin treatment to get your hair wet, so if you’re not a person who likes skipping wash day, then this treatment may not be right for you, and some people report a musty smell even after washing.
  • Not recommended for all. It’s also not recommended for pregnant women.

Keratin treatments can make frizzy, thick hair easier to manage.

The treatment works to smooth the hair’s cuticle which gives the strands a shiny look. It can also cut down on drying time.

The treatments are expensive however, and the formaldehyde in many formulas can be dangerous if inhaled, so make sure you’re getting the treatment done in a well-ventilated area or choosing a formaldehyde-free formula.