A keratin treatment is a process that smooths and often straightens hair. You might also hear it called a Brazilian keratin treatment or a Brazilian blowout. It involves applying products to the hair, blow-drying it, and sealing it with a flat iron.

Keratin is a natural type of protein in your skin, hair, and nails. A keratin treatment adds additional keratin to your hair, which can help to reduce frizz, increase shine, and strengthen hair. If you have curly or wavy hair, keratin treatments can also make your hair straighter.

Benefits

The specific benefits you’ll get from a keratin treatment depend on your hair type and the products used.

• Silky hair. Exposure to sun, hair dye, and other chemical treatments can strip your hair of naturally occurring keratin, leaving behind porous areas that are more vulnerable to breakage and other damage. Keratin treatments work to refill these areas that have lost keratin. The result is a smoother hair shaft, which translates to silky, shinier hair.

• Straighter hair. Depending on the products used, a keratin treatment can straighten curly or wavy hair.

• Smoother curls. Some formulas will simply reduce frizziness, providing softer, smoother curls or waves.

• Stronger hair. By replenishing lost keratin in your hair shaft, keratin treatments can make hair stronger and less prone to breakage. For some people, this might result in being able to grow hair longer, as the strands are less likely to break.

• Thicker-looking hair. In addition to strengthening hair, replenishing keratin through a keratin treatment can make hair appear thicker.