A Brazilian blowout is a semi-permanent hair smoothing and straightening treatment that uses a liquid keratin solution to create a protective layer around each strand of hair. This treatment smooths frizz, enhances shine, and makes hair more manageable by infusing keratin, a natural hair protein, which bonds to the hair and seals with heat using a flat iron

. The process typically takes about 90 minutes and involves applying a silicone-based or amino acid and protein-containing serum, then sealing it with heat. After treatment, hair should not be washed for at least three days to allow the keratin to bond properly

. The results usually last around three months but can extend up to 4-5 months with proper care, such as using sulfate-free shampoos and avoiding chlorine exposure

. While Brazilian blowouts are generally safe when performed by qualified professionals, there has been some controversy due to the presence of formaldehyde or its derivatives in some formulations, which are regulated or banned in certain regions due to health concerns. Modern Brazilian blowouts may avoid formaldehyde, but it's important to discuss product ingredients with your stylist

. Compared to keratin treatments, Brazilian blowouts deliver quicker results and use different chemical compositions, often combining amino acids and proteins rather than just keratin. Both treatments improve hair texture and shine but differ slightly in method and duration

. In summary, a Brazilian blowout is a popular, customizable hair smoothing treatment that reduces frizz and adds shine by applying a keratin-based solution sealed with heat, lasting several months with proper maintenance