Is Keratin Bad For Your Hair? Here’s The Damage It May Be Doing

Just like a glimpse of your fantastic hair day in the mirror can make it seem like you’re on top of the world, a streak of frizzy, flat, or damaged looks can feel like you’re stuck in a bad relationship — no matter what you do, you just can’t seem to work things out. Surprisingly, a common hair care ingredient may be to blame: keratin. That’s right — the material that makes up 95 percent of your hair fibers is actually a sneaky adversary in your quest for consistently great hair. Or, rather, keratin products.

If you’ve dealt with hair breakage, whether through chemical processing or heat styling, you’ve probably tried a few products that promise to repair and restore hair strength courtesy of this added protein. But the reality is that fixing your damaged fibers is not as simple as constantly layering on more keratin. “There is a misconception that incorporating keratin into a hair care regimen will increase the health or quality of hair fibers,” says certified trichologist Bridgette Hill. “Keratin is more complicated — it has more than one type of biochemical makeup in the hair fibers.” Board-certified dermatologist Dr. Joshua Zeichner adds, “While keratin does temporarily strengthen the hair shaft to help it resist environmental damage, it acts [more like] a surface patch and does not truly repair the foundation of the hair.”

Plus, too many of these products can actually exacerbate the issue. Says Hill, “The buildup of unnecessary protein blocks moisture from being able to move deeper into the inner structure of the hair fiber.” That lack of moisture means your hair is left dehydrated, frizzy, tangled, and full of split ends — aka the complete opposite of what you’re after. The key here is finding the ideal balance of moisturizing and protein-rich products for your texture and thickness so that you’re left with a strong, shiny, and manageable head of hair.

Keratin Overload

There is a tipping point that can indicate you need to cut back on keratin products. “A big sign that you have too much protein in your hair, or have been misusing products containing keratin or protein, is brittle hair, or hair that feels gummy when wet,” says hairstylist Erickson Arrunategui. “It almost looks like chemical damage.”

The reason for this lies in how keratin products interact with your hair fibers. Dr. Zeichner explains that the protein doesn’t just attach to the damaged part of your hair — it coats the entire shaft. “Whenever there is excess deposition of any residue on the hair, it can lead to a limp appearance,” he says. Luckily, unlike silicones, keratin proteins detach from the hair more easily and come off during regular conditioning — as long as you're not also using a keratin conditioner in your wash day routine.

If you think that overusing keratin products might be to blame for your recent hair issues, Arrunategui recommends first cutting them out of your regimen. Once you’ve done that, a weekly clarifying shampoo will rid your hair and scalp of excess buildup. Then follow up with a quality moisturizing conditioner, and “start using natural oils like jojoba to help protect and moisturize your hair.” And, although it might not be what you want to hear, avoiding heat and chemicals is a must — yes, that means you’ll have to reschedule that double process platinum you’ve been dreaming about for months.

Repairing The Damage

If you’re worried about treating lingering damage in hair that’s already overloaded with protein, Hill suggests avoiding anything that is promoted as “repairing” or “strengthening,” or has the word “keratin” emblazoned on the bottle. “There are some moisture-based proteins in high quality products that offer a safe approach to incorporating protein into your at home hair regimen,” she says. “Hydrolyzed wheat proteins from a reputable source are a safe option for someone in need of protein for strength and repair.” Consider this a reminder to use a moisturizing hair mask regularly.

Like most things in the beauty world, your hair won’t be fixed overnight — the experts all say that it may take a few weeks to notice the changes. But, if it means the overall health of your hair will improve, and your quality hair days won’t be so few and far between, that’s as good a reason as any to modify your routine and balance out your favorite protein-rich products with plenty of moisturizing options. Rest assured — a happy, healthy relationship with your hair is closer than you think.

Here, six vetted non-keratin hydrating products to keep your hair healthy and manageable.

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