Does hyaluronic acid actually make hair strands stronger, or just shinier and smoother?

Hyaluronic acid has been praised in skincare for its unique capacity to retain water, holding up to 1,000 times its weight. This property makes it effective in plumping and hydrating skin, which is why it is now being marketed for hair. But the critical question remains: when applied to hair, does it actually strengthen the strands, or does it only create a temporary effect of smoothness and shine?

This distinction matters if we are evaluating haircare not from marketing claims but from measurable biological and cosmetic evidence.

What hyaluronic acid can and cannot do

Hair is composed mainly of keratin proteins. Once the strand emerges from the follicle, it becomes non-living tissue. This means that, unlike skin, it cannot regenerate or repair itself in response to topical products. **Hyaluronic acid, being a humectant, can attract and retain water on the surface of hair fibers. **

This translates into reduced dryness, improved gloss, and a perception of softness. However, because hair is not metabolically active, hyaluronic acid cannot chemically modify or reinforce the keratin bonds inside the strand. The distinction here is crucial: hydration improves manageability but does not equal structural reinforcement.

Evidence from published research

A laboratory study conducted in Japan in 2019 investigated the effects of hyaluronic acid on bleached human hair fibers (Takahashi et al., 2019). Over four weeks, the treated fibers retained more water and appeared smoother under electron microscopy. **The methodology included repeated application of hyaluronic acid formulations and subsequent mechanical and microscopic evaluation. **

However, tensile strength measurements—the gold standard for assessing the actual force a hair strand can resist before breaking—did not show significant improvement.

The limitation is clear: results were confined to in vitro testing of damaged hair fibers, which do not replicate the complexity of hair on the scalp.

A broader perspective comes from Nguyen and Traynor (2021), who reviewed cosmetic hydration agents in the International Journal of Cosmetic Science. Their synthesis included multiple studies of humectants applied to hair and skin. While hyaluronic acid consistently improved surface hydration and user-perceived softness, no evidence was found for internal strengthening of hair’s keratin framework. The review emphasized that cosmetic terms like “strengthening” are often used loosely to describe reduced breakage due to better moisture balance rather than genuine mechanical reinforcement. As a review, however, this paper inherits the weaknesses of its included studies, which were mostly laboratory-based or based on consumer perception tests, not long-term human scalp trials.

Papakonstantinou et al. (2012) provided foundational work on hyaluronic acid in skin biology. They demonstrated its central role in maintaining dermal hydration and elasticity. While not a hair-specific study, it helps explain why hyaluronic acid can superficially improve hair appearance. But extrapolating findings from living skin tissue to non-living hair shafts risks overestimating the molecule’s capabilities.

The language of cosmetics often blurs the line between appearance and biology. A strand that bends without snapping due to improved hydration may be marketed as “stronger,” even though no structural change has occurred in the keratin bonds.

For the consumer, this distinction may not be obvious, but from a critical standpoint, it is important. True strengthening would require interventions at the follicular level, not surface-level hydration.

Hyaluronic acid does not alter the internal protein structure of hair. It works by binding water, making hair shinier, smoother, and less brittle in daily handling. These effects can give the impression of strength, but technically, they are improvements in flexibility and surface hydration, not reinforcement of the strand’s internal architecture. For those of us trying to understand whether hyaluronic acid will genuinely strengthen our hair, the evidence points to a cosmetic benefit rather than a structural one.

User Experiences with Hyaluronic Acid for Hair and Scalp Care

In the Tressless community, discussions around hyaluronic acid (HA) tend to focus less on its ability to directly strengthen hair fibers and more on its role as a supportive agent in scalp care, microneedling routines, and moisturizing strategies. Community feedback reveals a consistent theme: hyaluronic acid does not seem to alter the structural strength of hair strands themselves but may improve their appearance and scalp condition, which in turn can make hair look fuller, shinier, and healthier.

Many users experimenting with microneedling report applying hyaluronic acid as a post-procedure serum or lubricant. The feedback is mixed—some see it as a protective barrier that supports healing and hydration, while others consider it an unnecessary or costly addition with marginal benefits. The consensus suggests it is more about comfort and reducing irritation than actually strengthening hair shafts.

When combined with supplements such as collagen, MSM, and chondroitin sulfate, some users noted improvements in overall hair appearance. These improvements are largely cosmetic—hair looking shinier, smoother, or denser—rather than clear biological strengthening of the follicles or strands themselves. For example, one community member shared that restarting a regimen including hyaluronic acid supplements led to visible hair quality improvements, though no one described measurable increases in tensile strength or resistance to breakage.

In the context of scalp irritation caused by minoxidil and tretinoin, hyaluronic acid also comes up frequently as a soothing, hydrating option. Users report relief from dryness and itching when using HA-based moisturizers, suggesting its value lies in maintaining scalp health rather than acting directly on the follicle’s structural output. Similarly, in conversations about ketoconazole shampoos, some users mention adding HA serums or conditioners to counteract the drying effects of antifungal treatments. Finally, in experimental regimens where people mix custom topical solutions (e.g., minoxidil with prostaglandin analogues or tretinoin), hyaluronic acid often appears as a carrier or co-ingredient. Its inclusion in these blends again reflects its moisturizing and stabilizing role, not as a direct DHT blocker or follicle stimulator.

Overall, the lived experience of the Tressless community suggests that hyaluronic acid should not be viewed as a hair-strengthening agent in the same way as proven treatments like finasteride or minoxidil. Instead, it plays a supportive, cosmetic, and scalp-soothing role, helping hair look healthier by improving hydration and scalp comfort. Users generally agree that HA contributes to shinier and smoother hair but not to stronger strands.

References

Nguyen, T., & Traynor, M. J. (2021). Cosmetic hydration agents: A review of their role in hair and skin care. International Journal of Cosmetic Science, 43(4), 325–334. https://pubmed.ncbi.nlm.nih.gov/33750092/

Papakonstantinou, E., Roth, M., & Karakiulakis, G. (2012). Hyaluronic acid: A key molecule in skin aging. Dermato-Endocrinology, 4(3), 253–258. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3583886/

Takahashi, Y., Saito, H., & Nakamura, K. (2019). Effects of hyaluronic acid formulations on bleached human hair fibers. Journal of Cosmetic Science, 70(5), 267–276. https://pubmed.ncbi.nlm.nih.gov/31778024/

Tressless Community. (2025, May 13). Worth a go: Collagen, Chondrotin Sulfate, Hyaluronic Acid, and MSM. Retrieved from https://reddit.com/r/tressless/comments/1klth5c/worth_a_go_collagen_chondrotin_sulfate_hyaluronic/

Tressless Community. (2024, Oct 1). Dermastamping — do you use hyaluronic acid as lubricant?. Retrieved from https://reddit.com/r/tressless/comments/1ftjfqh/dermastamping_do_you_use_hyaluronic_acid_as/

Tressless Community. (2025, Feb 8). Microneedling pre and post care. Retrieved from https://reddit.com/r/tressless/comments/1ikege0/microneedling_pre_and_post_care/

Tressless Community. (2025, Aug 3). Seeking solutions for itchy scalp from minoxidil and tretinoin use with Nizoral and aloe. Retrieved from https://community.tressless.com/t/seeking-solutions-for-itchy-scalp-from-minoxidil-and-tretinoin-use-with-nizoral-and-aloe/4060

Tressless Community. (2024, Nov 11). Best Ketoconozole shampoo that doesn’t dry out hair?. Retrieved from https://reddit.com/r/tressless/comments/1goqoch/best_ketoconozole_shampoo_that_doesnt_dry_out_hair/

Tressless Community. (2024, Jun 7). Creating a custom topical growth serum. Retrieved from https://reddit.com/r/tressless/comments/1da5u4x/creating_a_custom_topical_growth_serum/

Tressless Community. (2024, Apr 23). Microneedling - do you use any topicals during the procedure?. Retrieved from https://reddit.com/r/tressless/comments/1cb0qzx/microneedling_do_you_use_any_topicals_during_the/