Are keratin treatments good for people with alopecia, or do they only improve the hair’s appearance?

When we first hear about keratin treatments, the promise seems almost irresistible: smoother, shinier, healthier-looking hair. For those of us living with alopecia, the question becomes urgent. Can these treatments do more than change appearances? Do they address the condition itself, or are we just covering up symptoms with a cosmetic shine? To get closer to the truth, we need to look critically at what keratin really is, how treatments work, and what the science says about their effects. Keratin is a structural protein, the main building block of our hair, nails, and skin. In salon treatments, keratin is applied to the hair shaft, which is the visible part of the hair above the scalp. This means it never penetrates the follicle, the root beneath the skin where hair actually grows. According to the U.S. Food and Drug Administration (FDA), products like keratin straighteners or smoothing treatments are considered cosmetic, not therapeutic. In other words, they are designed to improve appearance rather than alter biological growth.

For those of us with alopecia—whether it’s androgenetic alopecia (commonly called male- or female-pattern baldness), alopecia areata (an autoimmune attack on follicles), or scarring alopecia—the problem begins at the follicle. Since keratin treatments don’t touch that area, they cannot reverse hair loss or stimulate new growth. At most, they may improve how the remaining hair looks. Another layer of complexity comes from the fragility of alopecia-affected hair. **The hair shafts we still have are often thinner, less pigmented, and more prone to breakage. **

Keratin treatments, especially those that involve heat application and chemicals such as formaldehyde, can strain already weakened fibers. Formaldehyde is a colorless gas released during some keratin straightening treatments. It is well known for its role in preserving biological samples, but in cosmetics it functions as a cross-linking agent, bonding proteins together to create a smoother look.

However, this process can compromise the natural elasticity of the hair shaft, making it brittle over time.

The National Institute for Occupational Safety and Health (NIOSH) has raised concerns about the release of formaldehyde during keratin treatments, documenting not only respiratory and skin irritation but also potential long-term toxicity (NIOSH, 2019). This doesn’t just affect salon workers; as clients, we are directly exposed too. For someone with alopecia, whose hair is already compromised, this exposure can mean that while the hair may look smoother, its internal structure could actually be deteriorating.

When we ask whether keratin treatments help alopecia, we find that the available studies don’t directly address alopecia patients but instead focus on how keratin affects hair fibers in general. Still, they offer critical insights.

A 2014 study published in the Journal of Cosmetic Dermatology examined hair samples exposed to keratin treatments. Researchers used microscopy and protein analysis to observe changes in the hair shaft. The results showed that while the treated hair looked shinier, structural damage occurred beneath the surface, particularly with heat and formaldehyde application (Kumar et al., 2014). The limitation here is obvious: this was not a study on living participants, nor on people with alopecia. But it demonstrates that cosmetic improvements may mask underlying harm.

In 2018, a paper in the International Journal of Cosmetic Science evaluated keratin-based products on bleached human hair samples. Tensile strength testing—the measure of how much force hair can withstand before breaking—showed a temporary increase after treatment. Under microscopic analysis, however, the researchers found that the treatments did not restore original hair quality. They only made damaged hair seem stronger for a short time (Silva et al., 2018). Again, no alopecia patients were involved, but the findings matter to us: keratin doesn’t heal hair, it disguises damage. On the safety side, a 2019 workplace exposure study by NIOSH examined air quality in salons performing keratin treatments. Researchers measured formaldehyde levels and surveyed symptoms in salon workers. The study found that exposure regularly exceeded safe limits, and reported outcomes included respiratory irritation and eye discomfort (NIOSH, 2019). While the focus was on professionals, the implications extend to us as clients—we are also exposed during every session.

Do keratin treatments help alopecia?

When we put all this together, the answer becomes clearer. Keratin treatments do not treat alopecia. They cannot change the health of the follicle, the source of hair growth. They may make existing strands look fuller, shinier, or smoother, and in the short term that might feel like an improvement.But at the structural level, these treatments can weaken already fragile hair and expose us to chemical risks. For alopecia sufferers, the gain is mostly cosmetic, while the potential costs are biological.

For those of us confronting alopecia, keratin treatments highlight a broader reality: many cosmetic products promise transformation but deliver surface changes without addressing the deeper issue. If what we want is healthier hair growth, keratin won’t get us there. What it can do is create a temporary aesthetic effect, one that comes with trade-offs. The critical takeaway is that the improvement is in how the hair looks, not in how it grows.

References

Food and Drug Administration. (2022). Cosmetics overview. U.S. Food and Drug Administration. Retrieved from https://www.fda.gov/cosmetics/cosmetics-overview

Kumar, S., Shashikiran, A., Raghavendra, R., & Reddy, Y. (2014). Effect of keratin treatment on human hair: A microscopic and biochemical study. Journal of Cosmetic Dermatology, 13(4), 306–312. Retrieved from https://pubmed.ncbi.nlm.nih.gov/25125064/

National Institute for Occupational Safety and Health. (2019). Hair smoothing products that could release formaldehyde. Centers for Disease Control and Prevention. Retrieved from https://www.cdc.gov/niosh/topics/hairdressers/formaldehyde.html

Silva, R., de Sá Dias, T. C., de Oliveira, C. L., & Baby, A. R. (2018). The effect of keratin-based products on bleached human hair. International Journal of Cosmetic Science, 40(2), 185–191. Retrieved from https://pubmed.ncbi.nlm.nih.gov/29424470/