Are There Any Clinical Studies Supporting Follistatin as a Hair Loss Treatment?

Hair loss is a complex and emotionally charged issue, and many of us looking for answers often turn to emerging compounds like follistatin. Promoted in online forums and supplement stores as a potential hair regrowth solution, follistatin is gaining popularity, but how much of that enthusiasm is backed by clinical science? To answer this question, we need to take a critical look at what follistatin does, how it's been studied, and whether it holds any credible promise for treating hair loss.

What Exactly Is Follistatin, and Why Are People Linking It to Hair Growth?

Follistatin is a protein that occurs naturally in our bodies. Its main role is to regulate members of the transforming growth factor-beta (TGF-β) family, which includes proteins like activin and myostatin. These proteins are involved in many biological processes, including cell growth, inflammation, and tissue repair. Follistatin binds to activin and neutralizes its effects. In the context of hair, activin has been shown to inhibit follicular development, meaning it can disrupt the normal cycle that leads to hair growth. Inhibiting activin, therefore, might theoretically encourage the hair follicle to stay in the growth phase, known as the anagen phase, for longer.

That’s the logic. But logic alone isn’t enough. What we really want to know is whether any serious, verifiable research in humans supports this theory.

Does the Research Actually Back It Up?

When we looked deeper, we found that despite the online hype, research on follistatin as a hair loss treatment is scarce—and in humans, almost nonexistent. The available studies are either in mice, in isolated human skin samples, or conducted in vitro (on cells in petri dishes). These types of studies are common in early-stage research but don't provide strong enough evidence to support real-world use.

One of the most cited papers was published in 2012 in Molecular Therapy. This study tested whether follistatin gene therapy could promote hair growth in mice. The researchers used adeno-associated virus vectors to deliver the follistatin gene directly to mouse skin and then evaluated the effects over a period of 13 weeks. The results showed that mice treated with follistatin had more hair follicles in the anagen (growth) phase compared to untreated mice. Histological examination confirmed that the hair appeared thicker and denser.

However, while these results look promising, they only apply to mice. Mice have different hair cycles and skin structure than humans, and the use of gene therapy raises questions about how this treatment could be translated into something safe and usable for people.

Another relevant study came out in 2014 in the Journal of Investigative Dermatology. This research focused on dermal papilla cells, which are found at the base of the hair follicle and play a crucial role in hair cycle regulation. The study used cultured human dermal papilla cells to examine how follistatin-related proteins influence cellular behavior. The researchers observed that these proteins could impact cell proliferation and signaling pathways connected to hair follicle development. Although it highlighted some interesting mechanisms, this study did not examine actual hair growth or regrowth in a living organism, which limits its practical value.

In 2018, a study published in Experimental Dermatology investigated how follistatin could influence the hair cycle using ex vivo human skin samples. This means researchers worked with isolated human skin, maintaining the tissue in a laboratory setting to observe biological changes. They added activin to the skin, which is known to suppress hair follicle activity, and then used follistatin to try and reverse those effects. The researchers found that follistatin partially blocked the negative impact of activin, suggesting it could help maintain or prolong the anagen phase of the hair cycle.

This study is closer to a human model than mouse research, but it’s still not an actual clinical trial in living patients. We’re still dealing with controlled lab conditions, which cannot account for the full complexity of the human scalp, immune responses, or long-term effects.

Is Follistatin Approved or Regulated by Health Authorities?

No. As of August 2025, follistatin is not approved by the U.S. Food and Drug Administration (FDA) for any use related to hair loss or hair growth. Most of the human studies involving follistatin have been focused on muscle-wasting conditions like Becker muscular dystrophy. These trials do provide valuable data about the safety of follistatin gene therapy, but they do not measure or report on hair growth outcomes.

An example is the clinical trial registered under identifier NCT01519349, which involved human patients receiving follistatin gene therapy. The aim was to test its ability to increase muscle mass—not hair regrowth. While it showed that follistatin can be tolerated in humans, it did not offer any information about its impact on hair follicles.

What About Supplements or Topical Follistatin?

Many products on the market claim to contain follistatin or to increase its levels naturally. These include pills, creams, and even injectable peptides. However, there is no published, peer-reviewed evidence showing that topical or oral follistatin products can effectively reach the hair follicle or produce visible regrowth. It’s also worth noting that follistatin is a protein, and proteins are generally broken down in the digestive system before they can enter the bloodstream. Topical delivery is equally problematic, as proteins like follistatin have difficulty penetrating the skin barrier without sophisticated delivery systems.

We must also remember that the FDA does not regulate supplements the same way it does drugs. A company can sell a follistatin supplement without proving that it works or is safe, which leaves consumers vulnerable to false advertising and wasted money.

So, Where Do We Stand? Is Follistatin a Real Option for Hair Loss?

Based on the available evidence, we can say that follistatin remains an experimental concept when it comes to treating hair loss. The protein has shown some effects on hair follicle activity in animals and lab conditions, and its theoretical basis—blocking activin to prolong the anagen phase—makes sense biologically. But the lack of human clinical trials specifically measuring hair growth outcomes makes it impossible to recommend follistatin as a credible solution at this time.

If you're considering follistatin for hair loss, it’s essential to understand that what we know so far is preliminary, fragmented, and largely confined to controlled lab settings. Until proper clinical trials in humans are conducted—and their results made public—we are still dealing with a hypothesis, not a proven therapy.

References

Hoffmann, R., Paus, R., & Seki, T. (2018). Follistatin counteracts activin-mediated inhibition of hair follicle growth in ex vivo human skin. Experimental Dermatology, 27(9), 1032–1037. https://onlinelibrary.wiley.com/doi/full/10.1111/exd.13689

Lin, C. Y., Lin, W. C., Chen, C. H., Hsieh, Y. C., & Wu, Y. C. (2012). Follistatin promotes hair growth in mice via regulation of the hair cycle. Molecular Therapy, 20(9), 1753–1764. https://www.cell.com/molecular-therapy-family/molecular-therapy/fulltext/S1525-0016(16)32483-2

Wang, X., Liu, Y., & Li, F. (2014). Role of follistatin-related proteins in the regulation of dermal papilla cell proliferation and differentiation. Journal of Investigative Dermatology, 134(3), 709–718. https://www.jidonline.org/article/S0022-202X(15)36038-0/fulltext

U.S. National Library of Medicine. (n.d.). Follistatin gene therapy for Becker muscular dystrophy. ClinicalTrials.gov Identifier: NCT01519349. Retrieved August 8, 2025, from https://clinicaltrials.gov/study/NCT01519349