If you’ve ever hoped for smoother, frizz-free hair, chances are, you’ve heard of keratin hair treatments—or, at the very least, Brazilian blowouts. These smoothing hair treatments—which are one in the same—are known for their ability to make hair look straight, smooth, and shiny for up to six months. The only problem is, they’re loaded with chemicals and often get a bad rap as a result.
Because of that, and knowing full well just how beneficial keratin can be on its own as a haircare ingredient, beauty brands have begun formulating keratin-infused at-home products. But do they really work? To find out, we tapped the experts for everything there is to know about using keratin for hair. Ahead, find out the basics of the ingredient, as well as who it works best for and who should steer clear altogether.
Keratin for Hair
- Type of ingredient: Strengthening smoother
- Main benefits: Repairs the hair shaft, smoothes strands, adds shine
- Who should use it: In general, keratin is most beneficial for those with thick, damaged, frizzy hair. Folks with fine, fragile hair may not fare as well.
- How often can you use it: At-home keratin-infused products can be used daily. In-salon chemical keratin hair treatments, however, should be scheduled only once every few months.
- Works well with: “Since keratin is a naturally occurring protein with smoothing benefits that minimize frizz and make hair glossy and manageable, other products can reinforce the benefits of keratin,” cosmetic biochemist Stacey Steinmetz says, noting that natural oils like argan can help add moisture to damaged hair, and silicone-based finishing products can help further smooth the hair's surface.”
- Don’t use with: “If you have a salon keratin treatment in your hair, you need to stay away from sodium chloride, parabens, and sodium lauryl sulfates,” says BosleyMD-certified trichologist Gretchen Friese, noting that doing so will help maintain the integrity of the treatment. If you’re using gentler, at-home keratin-infused products, however, no ingredients are off-limits.
What Is Keratin?
“Keratin is a structural and protective protein that makes up hair and nails,” says cosmetic biochemist and StimuNail founder Stacey Steinmetz. “In hair, it’s responsible for preventing breakage, frizz, and heat damage. By applying keratin topically to your hair, it can be used to smooth and de-frizz.”
Before diving into the benefits of keratin for hair, let’s be clear on what keratin is and how it affects the hair. For starters, keratin is the cornerstone of hair structure. It’s a fibrous protein that quite literally forms each strand of hair. As hair becomes damaged, it needs all the help it can get to repair and boost its natural structure.
There are two main ways to add keratin into your haircare routine, and depending on which you choose, the benefits vary. “When hydrolyzed collagen proteins are applied topically on the hair, they can help fill in damaged areas of the hair shaft, temporarily boosting the strength,” says New York City–based dermatologist and adviser for Collective Laboratories Hadley King, MD. “This is different from [in-salon] keratin treatments that generally feature formalin (formaldehyde and methyl alcohol) to straighten hair. Those treatments can damage hair and release dangerous fumes.” Despite those potential dangers, many people still book in-salon keratin treatments. With that in mind, ahead you’ll learn the pros and cons of both at-home and in-salon keratin hair treatments.
Benefits of Keratin for Hair
- Smoothes hair
- Strengthens hair
- Adds shine
Whether you opt for an in-salon or at-home keratin hair treatment, you can expect to notice a difference in your hair. “At-home keratin products help to strengthen hair that has been compromised by chemical and mechanical damage,” Friese says. In doing so, these products—which often come in oil or serum form–can result in a smoother, shinier, healthier-looking mane.
In-salon keratin treatments, on the other hand, use liquid keratin, chemicals, and high heat to seal the protein into the hair.
“The results are temporary and typically last up to six months,” Steinmetz says. The problem is, in order to garner those benefits, you have to expose yourself to potentially harmful chemicals, which is why Brazilian blowouts often get a lot of flack.
Hair Type Considerations
Keratin treatments—at-home or in-salon—work best for people with dry, damaged, and overall unruly hair types. Additionally, Steinmetz says that keratin treatments can be great for folks looking to achieve a fuller look, as it’s said to bind to thin hair and give it a fuller look. Though, that’s somewhat of a double-edged sword because, as Steinmetz points out, fragile strands can be overwhelmed by the harsh chemicals within an in-salon keratin treatment, not to mention the heat damage required to seal it in.
As far as who shouldn’t get an in-salon keratin hair treatment, Steinmetz says pregnant people and folks with preexisting respiratory issues should steer clear. “Salon keratin treatments contain large amounts of formaldehyde,” she admits. “Some hairstylists have reported respiratory problems from handling the keratin treatment products and inhaling their fumes repeatedly over time. For that reason, pregnant women should avoid getting this treatment. People with a sensitivity to formaldehyde or respiratory problems should also avoid keratin treatments.”
That doesn’t mean you have to avoid at-home keratin treatments, though. After all, those are much safer and do not contain the chemicals and fumes associated with in-salon techniques.
That said, Friese points out that there is such a thing as too much protein. “If the hair is feeling dry after using a keratin product, stay away from that kind of treatment and use one with moisture instead,” she instructs.
How to Use Keratin for Hair
While in-salon keratin treatments are technically an option, more often than not, they’re not recommended. That said, Steinmetz points out that there are shampoos, conditioners, and finishing products that apply a layer of keratin to the hair to temporarily make it look shiny and glossy, while reducing frizz—though the benefits are short-lived. That doesn’t make these at-home products undesirable though. After all, would you rather have to apply a product daily or weekly and enjoy healthy-looking hair, or get a one-time in-salon treatment with the potential to damage your hair and lungs in the process? Exactly.
With that in mind, if you’re hoping to strengthen your hair and add loads of shine before a big event or simply as part of your weekly routine, Friese recommends stocking your at-home haircare routine with L'ANZA Keratin Healing Oil Hair Treatment ($32), Keratin Complex Infusion Keratin Replenisher ($30), and Paul Mitchell Awapuhi Wild Ginger Keratin Intensive Hair Treatment ($30), all of which are applied to damp hair and either rinsed out or blow-dried in.
The Final Takeaway
As trendy and convenient as in-salon keratin treatments may seem, the amount of harm they can cause to your hair makes them simply not worth it. As a result, if you’re looking to smooth and strengthen your hair for special events or even daily occurrences, opting for safer, gentler at-home formulas is the way to go. But, whatever you do, never try to re-create an in-salon keratin treatment at home. “The combination of ingredients could be quite irritating,” Steinmetz warns.