Are Brazilian Blowouts Bad For Your Hair?

Are Brazilian Blowouts Bad For Your Hair?

With extra cash in our pockets and a burning need to look our best as we re-entered society these past few years, many have turned to keratin treatments to smooth their frizzy locks and get them under control. The 2016 release of REVLON’s One-Step hair dryer and volumizer led the way for more affordable, versatile at-home beauty options, while 2018 saw the release of Dyson’s Airwrap™ styler at a much higher price point. Many women are familiar with keratin treatments, Brazilian Blowouts, and similar at-home options, but many more have questions. How do Brazilian Blowouts work? Are the ingredients and methods safe? How do I get the best value for my style? We’ve got you covered.

What Is A Brazilian Blowout?

First, it’s important to understand that a Brazilian blowout is a branded type of keratin treatment, rather than a category of treatment itself. As we’ve discussed in previous posts, keratin is the protein that makes up most of the hair shaft. The part of the hair that we touch, the cuticle, is covered in keratin—when we’re aiming to improve texture and shine, treating the hair cuticle is the way to go.

A key part of keratin treatments and Brazilian blowouts isn’t just the product that’s applied, but how the product itself is activated and bonded to the hair. This involves not only carefully applying the keratin treatment or Brazilian blowout solution to the hair, but locking it in with high levels of heat using a flat iron or other heated styling tool. The result is similar to laminating a piece of paper by locking in a fixed shape with a solid outer layer.

What’s In A Brazilian Blowout Treatment, And How Does It Work?

What Factors Contribute To Hair Texture?

When discussing Brazilian blowouts, it’s essential to step back and understand what contributes to hair texture in the first place. Hair is thought to get its texture—straight, wavy, curly, or tightly curled—from a variety of factors, but the shape of the hair follicle itself is thought to be significant. Those of us with straight hair typically have straight hair follicles that allow the hair shaft to emerge in a straight path, unimpeded, until it reaches above the skin’s surface. Those of us with wavy or curly hair, however, have hair follicles with a bit of a curve or crescent shape to them.

Why is this important? Brazilian blowouts make use of chemicals to achieve their unique look, and this portion of our hair’s chemistry helps to explain why those ingredients are necessary! 

When it comes to proteins like keratin, there are three main types of protein-protein bonds that we should talk about: hydrogen, ionic, and covalent bonds. Hydrogen bonds are weakest and, without any type of semi-permanent treatment like a Brazilian blowout, form between keratin proteins as hair dries and break down when hair gets wet. Think of how your hair naturally straightens after showering or when you get caught in the rain, then curls up as it dries—hydrogen bonds between keratin proteins are the culprit!

The Chemistry Of Hair Texture And Hair Care Products

When the follicle is curved, it forces the growing hair shaft to curve, too, before the hair strand emerges above the surface of the skin. As the hair shaft grows out from the hair follicle, the keratin proteins that pack together to give our hair its structure find themselves more closely packed on the “inner” side of the curved follicle than on the “outer” side. When the proteins are packed more tightly together, they’re more likely to form a different, stronger type of bond, known as a covalent bond. Unlike the more temporary hydrogen bonds, covalent bonds aren’t impacted by simply adding or removing water: Making a covalent bond, like with a keratin treatment or as part of a Brazilian blowout, requires a chemical—like formaldehyde—to form the link, while breaking a covalent bond requires a different chemical to undo the same link.

These chemicals that undo covalent bonds between keratin proteins are known as relaxers because they help to relax the tightness of curls and waves found in our hair. A chemical often used in hair straightening, particularly in thermal reconditioning or Japanese hair straightening, is ammonium thioglycolate (ATG). Named after the type of bond that it targets, ATG is known specifically as a thio relaxer.

Safety Concerns In Brazilian Blowouts And Keratin Treatments

Why Do Brazilian Blowouts Use Formaldehyde?

The urban legend behind the origins of the Brazilian blowout goes something like this: A Brazilian mortician noticed that embalming fluid—with its high levels of formaldehyde, a preservative chemical—often straightened the hair of the bodies they worked on in funeral homes, and figured that the same mix of chemicals might straighten hair the same way for the living.

Formaldehyde is a key ingredient in the Brazilian blowout because of its ability to chemically bind proteins together. If broken, damaged hair is a result of damage to the keratin layered in our cuticles, applying additional keratin as a supplement can fill in some of the cracks. Just slathering on extra keratin isn’t enough to make it stick, however: Making and breaking chemical bonds takes a lot of energy, which is where the added heat from a blow dryer or beauty tool comes in. By applying the added heat to the already-applied Brazilian blowout formula, the additional keratin in the formula can successfully bind to the keratin that’s already in your hair without washing away the instant you shower. Once bonded, the laminate-like layer of supplemental keratin is locked in, though it’s recommended to avoid getting the hair wet for a few days after the treatment.

Are Brazilian Blowouts Safe?

So far, so good, right? Not quite! The drawback to keratin treatments like the Brazilian blowout is the use of harsh chemicals like formaldehyde. While formaldehyde is present in many things we use on a daily basis—think the resin layer on some wood surfaces, paints, treated fabrics, as well as in some consumer products like medicine, cosmetics, or detergents—it’s usually present in low amounts. The increased popularity of the Brazilian blowout treatment brought additional scrutiny from both the CDC and OSHA, with both finding that levels of formaldehyde gas during the Brazilian blowout treatment exceeded safe levels, particularly for the salon workers who work with it on a regular basis.

Manufacturers attempted to work around the formaldehyde backlash by labeling products as “formaldehyde-free”, instead claiming that they contained methylene glycol or methanediol. This labeling was purposefully deceptive, however: Methylene glycol and methanediol are names for the hydrated version of formaldehyde that results when it dissolves in water. As you might imagine, when you’re applying a flat iron or dryer to the hair at high temperatures, that water will evaporate off, leaving formaldehyde behind.

The primary risk for formaldehyde exposure is when surfaces that contain it begin to “leak” gaseous formaldehyde in a process known as off-gassing, which we then breathe in. According to the EPA, formaldehyde can irritate our skin, eyes, nose, and throat, and in high amounts over long periods of time, can cause certain types of cancer. Not quite the chemical we’d want to frequently apply to our hair!

Are Brazilian Blowouts Bad For Your Hair?

Despite formaldehyde being a toxic chemical and a necessary component of Brazilian blowout treatments, formaldehyde itself doesn’t damage the hair shaft. The solution containing formaldehyde may irritate the scalp, and long-term exposure to any formaldehyde gas given off during the heating process can be a health hazard. The primary damage to the hair itself with at-home treatments can come from the use of flat irons and other tools that apply heat and traction to the hair shaft. Depending on the tools and techniques used when attempting an at-home Brazilian blowout, as well as your skill and familiarity with the necessary steps, attempting to perform the heat treatment could cause hair damage, scalp irritation, and chemical exposure.

Alternatives To Brazilian Blowouts

Thermal Reconditioning

Now that we’ve covered that bit of chemistry, how does it apply to Brazilian blowouts or alternative hair straightening treatments like thermal reconditioning? Remember: If the curve of our hair follicle helps to form the protein-protein bonds that give our hair its waves and curls, once the hair is above the surface of the skin, those bonds are unlikely to reform once they’re broken. That’s what makes Japanese hair straightening a permanent type of treatment.

By adding an activator like ammonium thioglycolate, the bonds holding keratin proteins together are broken and the hair begins to straighten. The activator is then rinsed out, and with newly-relaxed hair, the strands are aligned and straightened using a flat iron before a neutralizer like hydrogen peroxide is applied to reform some of the protein-protein bonds that were initially broken by the ammonium thioglycolate. This time, however, the bonds will be locked into a straight position, rather than the curlier look they initially had!

At-Home Keratin Treatments

As we’ve discussed above, hair treatments like the Brazilian blowout or Japanese hair straightening rely on harsh chemicals like formaldehyde or ammonium thioglycolate to achieve their results. Because the Brazilian blowout and other types of keratin treatments straighten the hair in a process that’s similar to lamination, they require the solution to be applied evenly and for the proper amount of time—something that can be difficult to achieve at home, particularly when working with toxic chemicals that can emit high amounts of formaldehyde. At-home treatments will often have lower concentrations of the active ingredients and won’t achieve the same level of straightening, frizz control, or shine as a professional treatment done at a salon. Similarly, at-home keratin treatments often won’t last as long as salon treatments and will have to be redone more frequently to maintain the desired look.

So, Are Brazilian Blowouts Risky?

We’ve reviewed the history behind the Brazilian blowout, looked over the science behind hair texture, and explained how the underlying chemistry of different hair care products can achieve certain looks. Is the Brazilian blowout look right for you? More importantly, is it safe? When approved products are applied by trained professionals in a well-ventilated salon, the Brazilian blowout can be a calculated risk.

Does a Brazilian blowout increase your risk for hair loss? The active ingredient in the treatment, formaldehyde, may irritate the skin and scalp, but the primary risk of formaldehyde exposure comes when it’s breathed in as a gas. In harsher treatments like thermal reconditioning, the chemical formula may be more irritating. The primary risk for hair loss or damage comes from uneven application of heat to the hair, or from accidental burns and irritation during the ironing process.

Whether you decide that a Brazilian blowout is the right choice for your look, it never hurts to make sure that your hair is thick and healthy enough to support the style you’re aiming for. That’s why we recommend our Hair Revival Serum as part of your daily routine, whether you’re rocking the Brazilian blowout look or not!

Profile photo for Enzo Benfanti

Reviewed by: Enzo Benfanti, MEng

Enzo is a chemical engineer and data enthusiast with a background in industrial chemicals. His previous experience is in developing catalysts and designing industrial chemical processes to produce the precursors to detergents, polyester fibers, and other specialty materials. He received his bachelor’s degree from the University at Buffalo [Go Bills!] and his master's degree from Columbia University, both in chemical engineering.

Written by: Revela Editorial Team

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