Does hyaluronic acid accelerate hair growth?

The hair cycle follows a very specific process in 3 major phases : the anagen phase, or growth phase, the catagen phase, or resting phase, and the telogen phase, or shedding phase. The hair shaft originates at the root of the hair follicle, specifically at the level of the dermal papilla, which is richly innervated and promotes the proliferation and growth of keratinocytes as well as the induction of new hair follicles. The dermal papilla is a site of exchange that allows the hair to receive the various nutrients and oxygen necessary for its growth. 3 to 6 years after the birth of the hair, a physical rupture occurs between the dermal papilla and the hair bulb where the shaft is anchored. No longer receiving the elements it needs, the hair stops growing and falls out on its own after a few months.

There are few active ingredients capable of influencing the hair growth cycle. As for hyaluronic acid, there is currently no scientific evidence of its effectiveness on hair growth when applied topically. However, an in vitro study suggests its potential. Conducted on human follicles, it showed that hyaluronic acid increases the secretion of vascular endothelial growth factor (VEGF), a key mediator of angiogenesis. By triggering the formation of new blood vessels, VEGF supports tissue growth and promotes hair growth. The following table details the effects of hyaluronic acid on VEGF activity observed by researchers.

Furthermore, a clinical trial involving 12 men examined the effects of hyaluronic acid injections on androgenetic alopecia. Over eight weeks, the volunteers received targeted injections of a hyaluronic acid-peptide complex every two weeks. The results were monitored six months later and are recorded in the following table. They demonstrate the real effectiveness of this method on androgenetic alopecia, achieved without side effects in this study. However, it is important to note that the observed improvement cannot be attributed to hyaluronic acid alone, as it was combined with peptides.

Furthermore, it is advised to exercise caution regarding hyaluronic acid injections. Indeed, while these procedures are generally successful, certain cases of skin reactions should raise concern (edema, erythema, pain...). This also applies to hyaluronic acid injections in the scalp. A 54-year-old patient recently experienced discomfort following this procedure. After reporting pain from hyaluronic acid injections, she noted discoloration, itching, and crusting on her scalp. 18 days later, the patient suffered a significant hair loss in the areas where the injections had been administered. Hyaluronidases, enzymes that degrade hyaluronic acid, were then urgently injected, resulting in the disappearance of the pain two days later. The patient's hair subsequently grew back normally, but this episode serves as a reminder that, while aesthetic dermatology has many benefits, the risk of side effects is always present.

Key Points to Remember :

• Currently, no study has shown that topical application of hyaluronic acid accelerates hair growth.

• Hyaluronic acid injections combined with peptides are effective in combating hair loss, but the potential side effects can be severe.