Brazilian Blowout vs Keratin Treatments: Are They Safe for Aging Hair?


If you’re looking for silky, frizz-free hair that lasts through washes, the Brazilian Blowout and other similar keratin treatments are the gold standard—after all, they’ve been the go-to treatments many women have turned to since the early 2000s. But as with any permanent or semi-permanent hair treatment that involves chemicals, it’s essential to research before jumping in headfirst.

We’ve heard women asking if the Brazilian Blowout has an age limit or if they can pull off a Brazilian Blowout after menopause. Are Brazilian Blowouts safe for fine, thin hair? For gray hair?

We are here to tell you that whether you’re 40, 50, or 60, there is no age limit for Brazilian Blowout or keratin treatment. But that doesn’t necessarily mean they are all safe for the delicate disposition of aging hair and its long-term health.

If you’re curious about what these treatments entail or are confused about their differences (we wouldn’t blame you; the names are often used interchangeably!), we have everything you need to know about the Brazilian Blowout vs other keratin treatments for your delicate, aging tresses.

Brazilian Blowout vs Keratin Treatments: What’s the Difference?

First, let’s set the record straight: A Brazilian Blowout is just one of the many keratin treatments available today.

In fact, all hair-smoothing treatments contain keratin, even though keratin isn’t the ingredient responsible for straightening and smoothing hair (more on that below).

The Brazilian Blowout differs from other keratin treatments because it is a trademarked name of a patented product. So, if you walk into any salon that offers a Brazilian Blowout, you will receive the same formula no matter where you are in America.

Other keratin treatments can vary considerably in their chemical composition—some are almost identical to the results of the Brazilian Blowout, while others are significantly gentler and safer.

What Does a Brazilian Blowout Do to a Woman’s Hair?

Brazilian Blowouts and similar keratin treatments leave a protective layer on the hair shaft, which is how the treatment stays effective for weeks, even through shampooing. This layer that keeps the treatment in the strand also serves as a protective barrier that keeps damaging environmental elements out of the strand.

In theory, it might seem like this extra layer of protection, which also gives the hair strands their glossy, silky-smooth look, makes a Brazilian Blowout beneficial for thin, aging hair, but keep reading to find out why this isn’t necessarily the case.

Why Does the Brazilian Blowout Get a Bad Rap?

The Brazilian Blowout is long-lasting and incredibly effective, but this doesn’t come without a price. The Brazilian Blowout contains carcinogenic chemicals, namely formaldehyde—and the concerns about using formaldehyde in the patented formula remain. In fact, the current formula cannot be used in California after 2025 due to new safety regulations.

But the Brazilian Blowout isn’t alone in this regard. Other keratin treatments also involve formaldehyde or derivatives that release formaldehyde during the treatment—but not all do. Many keratin treatments contain gentler formaldehyde-free alternatives with glycolic acid and ​​sericin.

Why Do Keratin Treatments Contain Formaldehyde?

Despite being called keratin treatments and containing keratin, keratin isn’t the star of the show—formaldehyde is what straightens your hair. It’s necessary to ensure that the keratin treatment binds to the hair. This is why the Brazilian Blowout is known as the superstar in hair smoothing and straightening. A comparison study found that the original Brazilian Blowout brand solution contained formaldehyde concentrations of 11.5%, almost three times higher than other brands.

Keratin treatments that contain smaller amounts of formaldehyde don’t offer the same straightening results. And those that don’t contain formaldehyde at all only deliver smoother, shinier, frizz-free hair as they don’t alter the texture of the hair (i.e., straighten it)—but smooth, shiny, frizz-free tresses are still a win, wouldn’t you agree?

How Safe Is a Brazilian Blowout for Thin Hair?

During midlife and especially as we move through menopause, our hair becomes more delicate; it often thins, and even our scalps can become more sensitive. This makes the Brazilian Blowout during menopause an unfavorable hair treatment that can harm your fine, thinning hair, especially over time.

The biggest culprit for hair damage when a Brazilian Blowout is performed on thin hair that is also delicate, and aging is the high heat used during the treatment to create smooth, glossy results. High heat is extremely harmful to delicate hair. Formaldehyde in keratin treatments has also been linked to causing scalp irritation, which could ultimately lead to hair loss. Besides the safety concerns, other downsides of keratin treatments, like the Brazilian Blowout, for thin hair involve the topic of volume.

Many women find that building volume becomes even more challenging after receiving a Brazilian Blowout on their thin hair because the strands are now simply too sleek and lacking in strength and structure to have a lift. As a result, their hair can feel very flat and limp and even be more prone to becoming greasier more easily.

Lack of volume and an increased likelihood of greasier strands is especially an issue for women with thin, straight hair. However, if you have thinning hair that has a naturally curly texture, there may be a way for you to get around the volume issue.

Are Keratin Treatments Customizable?

You may have heard that one benefit of the Brazilian Blowout (and other keratin treatments, with and without formaldehyde) is that it is customizable. This is true. Depending on how a keratin straightening treatment is applied and for how long, it can produce sleek, straight strands, flowing waves, or bouncy, shiny curls. You can even ask your stylist to apply the treatment differently to different sections of your hair for a truly one-of-a-kind style.

If you have thinning, curly, or wavy hair and don’t opt for a super-straight style, you can still get the benefits of smooth, tamed, frizz-free strands without losing so much of your volume. Plus, the likelihood of greasier locks will be diminished as your scalp’s natural oils won’t be able to travel down the hair shaft as easily as they would with straight strands. Just be sure to work with an experienced stylist to get the best results.

And remember, a volume-boosting spray like our Lift Me Up Hair Thickener is always the safest way to give your tresses a volumizing boost.

All this being said, there is one caveat with any keratin treatment: Everyone’s hair responds differently to these treatments, and factors like the porosity of your hair all play a role, so it’s entirely possible if the goal for your naturally curly hair is sleek poker-straight strands, you may be out of luck.

Why a Smoothing Treatment May be a Better Option for You

If your goal isn’t to manipulate your hair texture and you’re only after smoother, shinier, frizz-free hair, consider one of the many formaldehyde-free hair smoothing formulas that are gaining popularity as a safer Brazilian Blowout alternative.

These safer Brazilian Blowout alternatives are more focused on softening your hair while adding silkiness and shine, and they use ingredients such as glycolic acid and ​​sericin instead of formaldehyde. This means you’ll get smooth, frizz-free results but still have your natural waves or curls if you air-dry your hair—as well as all your former volume! But when you use a blow-dryer to straighten it (and never forget to apply your heat protection spray first), you’ll enjoy many benefits—the treatment reduces frizz, increases shine, and speeds up drying time, too! 

Other advantages of these safer Brazilian Blowout alternatives include the option to color your hair on the same day if you desire (though if you’re having more than one process done in a visit, request a hair protectant between treatments) and not having to worry about the treatment weakening your hair follicles over time.

If the harmful consequences of formaldehyde have prevented you from trying a Brazilian Blowout on your gray hair, a formaldehyde-free keratin smoothing treatment is certainly something to consider. Just beware of brassiness: Because keratin treatments penetrate the hair shaft, hair strands containing blonde or silver colors can turn yellow.

But there’s an easy fix for brassiness from Brazilian Blowouts on blonde or gray hair. If you notice your light-colored locks look a bit yellow following treatment, use a purple shampoo like our Silver Lining Purple Brightening Shampoo to combat brassiness, and follow it up with our cuticle-sealing Silver Lining Purple Butter Masque to help extend the life of your keratin treatment.

But Are Smoothing Treatments Safe for Aging Hair?

Even when you strip formaldehyde out of the equation, keratin smoothing treatments require heat to close the cuticle and lock the ingredients into the hair. This makes even gentler smoothing treatments (not to mention formaldehyde-laded keratin treatments like the Brazilian Blowout) problematic for fine hair due to its fragile nature. Damaged and delicate, aging hair is highly vulnerable to this high-heat aspect of these treatments. But there are some brands out there these days that are developing keratin-smoothing treatments for fine, fragile hair. They are activated at a lower heat, which makes them a lot safer, plus they even promise not to compromise the color of blonde or silver hair.

Regardless of your treatment, your at-home hair care is an important before and after step for your delicate tresses. We recommend weekly deep conditioning treatments, like our Hair Redemption Restorative Butter Masque, that add hydration while sealing in moisture to protect the hair shaft and extend the length of your smooth style. And gentle yet effective sulfate-free shampoos and conditioners are essential for nourishing, strengthening, and hydrating your hair every time you wash.

Do Keratin Treatments Strengthen Aging Hair?

Keratin is a protein found in our hair. And while keratin smoothing products add fortifying proteins to our tresses, their primary goal isn’t to strengthen hair but to smooth it and add shine (and when formaldehyde is involved, straighten it). But since a side effect of shinier, smoother strands is less breakage, your hair will certainly look healthier and stronger and feel more manageable after a keratin treatment.

If you are considering a keratin treatment for its hair-fortifying benefits and straightening isn’t a goal, ask your stylist for a formaldehyde-free keratin treatment.

How Can I Make Keratin Treatments Safer?

One way to lower the risks of a keratin treatment with formaldehyde is by receiving your treatment in a well-ventilated salon and wearing a mask to your appointment.

Another option is to request a treatment that uses vanillin as an alternative. Keratin treatments that use a much smaller amount of a food-grade preservative known as “vanillin” avoid the health and safety concerns surrounding treatments using formaldehyde. Note that vanillin is also known as “aldehyde,” so while it’s considered safer by the FDA, it is still in the same family of preservatives as formaldehyde.

To make keratin treatments, like the Brazilian Blowout, safer for thin hair and the overall long-term health of your hair, the best route is to consider a copycat treatment that’s formaldehyde-free. This is an excellent option if your hair goals don’t include super-straight strands, as one of the safest Brazilian Blowout alternatives is a relaxant-free smoothing treatment. A low-heat formaldehyde-free keratin treatment designed for fragile, aging hair is a terrific option, too.

Before You Head to the Salon…

When deciding if a keratin treatment is proper for you, do your research and weigh all the benefits against the risks to your health (and your stylist’s) and the health of your hair. When you meet with your stylist, know what procedure to ask for and know that your results may vary as everyone’s hair takes different treatments.

Be sure to discuss the products they use and ask about the ingredients they contain to see if they include formaldehyde or formaldehyde derivatives. Finally, discuss the post-treatment expectation for how long the results will last and any restrictions immediately following your procedure, as they can vary depending on the treatment.

Tell Us: Have you tried a keratin treatment, Brazilian Blowout, or another safer alternative? Please share your experience with us in the comments below! 

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To maintain your sleek, glossy style regardless of which keratin hair treatment you choose, Better Not Younger has sulfate- and paraben-free products to support gorgeous aging tresses! If smooth, frizz-free strands are what you crave, check out our entire line of frizz-fighting vegan hair-care products, and let us help you achieve the sleek style you envision!