How Does sh-Polypeptide-7 Help Stimulate Hair Follicle Activity or Reduce Scalp Inflammation?

Understanding sh-Polypeptide-7 in Simple Terms

sh-Polypeptide-7 is the cosmetic industry name for a laboratory-produced version of a natural human protein called Epidermal Growth Factor, often shortened to EGF. Growth factors are substances naturally found in the body that send signals to cells, telling them when to grow, repair themselves, or calm down after irritation. EGF was first discovered in the 1960s and has since been widely studied in skin healing, inflammation control, and cell regeneration. In hair and scalp products, sh-Polypeptide-7 is used because of its ability to communicate with skin and hair follicle cells in a gentle but powerful way.

To understand how it may help with hair growth and scalp inflammation, it is important to first understand what hair follicles are. Hair follicles are tiny structures in the skin that produce hair strands. They go through cycles of growth, rest, and shedding. Inflammation, poor blood supply, or damage to the surrounding skin can interrupt these cycles, leading to thinning or hair loss.

EGF works by attaching to special receptors on the surface of cells. These receptors act like locks, and EGF acts like a key. Once EGF binds to these receptors, it activates internal signals that encourage cells to divide, repair damage, and reduce stress responses. In hair follicles, these signals are important because the cells at the base of the follicle are some of the fastest-growing cells in the body. They need constant support to stay active. When inflammation or aging disrupts these processes, follicles can shrink, produce thinner hair, or stop producing hair altogether.

Research has shown that EGF influences the activity of keratinocytes, which are the main cells in the outer layer of the skin, and dermal papilla cells, which are essential for controlling hair growth cycles. By supporting these cells, sh-Polypeptide-7 may help maintain a healthy environment for hair production.

Encouraging Hair Follicle Activity: What Research Suggests

Several scientific studies have explored how EGF affects hair follicles. In laboratory and animal models, EGF has been shown to influence the hair growth cycle.

A notable study conducted in 2012 by researchers in South Korea investigated the effects of EGF on hair follicle cells in mice. The researchers applied EGF to shaved areas of mouse skin over a period of four weeks. Hair regrowth was monitored visually and through microscopic examination of hair follicles. The study found that areas treated with EGF entered the growth phase, known as the anagen phase, faster than untreated areas. The follicles were larger and showed increased cell activity. However, the researchers also noted that excessive EGF could slow hair shaft formation, meaning that balance is important.

The criticism of this study lies in the fact that it was conducted on animals, not humans. Mouse hair cycles are much shorter and behave differently from human hair cycles. While the results are promising, they cannot be directly translated to human scalp conditions without further research. Another laboratory study published in 2016 examined human dermal papilla cells grown in culture. Researchers exposed these cells to EGF and measured cell growth using microscopic counting and protein activity tests. The results showed increased cell survival and signaling related to growth and repair. This suggests that EGF can directly support the cells responsible for hair follicle function.

The limitation here is that cells grown in dishes do not experience the complex environment of real human skin, where hormones, immune responses, and blood flow all play roles.

Calming the Scalp: sh-Polypeptide-7 and Inflammation Reduction

Inflammation is the body’s natural response to irritation or injury, but chronic inflammation on the scalp can harm hair follicles. Conditions like dandruff, dermatitis, and even androgenetic alopecia (pattern hair loss) are associated with increased inflammatory markers. EGF has been widely studied for its anti-inflammatory and skin-repair properties, particularly in wound healing and dermatology.

A clinical study published in 2011 evaluated the effects of topical EGF on patients with skin irritation after cosmetic laser treatments. The study involved 40 human participants over a period of two weeks. Researchers applied EGF cream to treated skin and measured redness, swelling, and healing speed using visual scoring and skin imaging tools. The EGF-treated areas healed faster and showed significantly reduced inflammation.

The criticism of this study is that it focused on damaged facial skin rather than the scalp specifically. However, the biological processes of inflammation and skin repair are similar across body areas.

Another study in 2018 investigated EGF’s effect on inflammatory chemicals called cytokines in human skin cells. The researchers induced inflammation in laboratory-grown skin cells and then treated them with EGF. Over 48 hours, they measured cytokine levels using biochemical assays. The results showed a decrease in inflammatory markers such as interleukin-6 and tumor necrosis factor-alpha, both known to contribute to tissue irritation and follicle stress.

The limitation is again the laboratory setting, which does not fully represent living human skin.

The Role of a Healthy Scalp Environment in Hair Growth

Hair follicles do not exist in isolation. They depend on surrounding skin, blood vessels, and immune cells. When the scalp is inflamed, blood flow can be reduced and harmful substances can build up around follicles.

By encouraging skin repair and reducing inflammatory signals, sh-Polypeptide-7 may create a more supportive environment for follicles to function normally. This does not mean it acts as a miracle hair regrowth treatment, but rather as a supportive ingredient that may help follicles perform at their best when combined with good scalp care.

Current Limitations and the Need for Human Hair-Specific Studies

While EGF has strong scientific backing in skin healing and cellular regeneration, direct long-term human studies focusing solely on hair growth are still limited. Most evidence comes from animal models, cell cultures, or related dermatology research. Scientists emphasize that growth factors work best as part of a broader approach including proper nutrition, scalp hygiene, and in some cases medical treatments. Overstimulation of growth factor pathways may even have negative effects if not properly controlled.

*This highlights the importance of cautious optimism. sh-Polypeptide-7 shows potential, but it should not be viewed as a standalone cure for hair loss. *

Research Evidence in Detail

One of the foundational studies on EGF and hair cycling was conducted in 2012 using mouse models over four weeks, employing visual hair growth scoring and histological follicle analysis. While effective in accelerating growth phase entry, its animal-based design limits human application. The 2016 human dermal papilla cell study used in-vitro cell cultures, protein expression measurement, and cell viability counting across several days. It demonstrated enhanced cellular activity but lacked real-world biological complexity.

The 2011 clinical trial involving post-laser skin healing measured inflammation visually and through imaging over two weeks in 40 participants. It confirmed EGF’s inflammation-reducing and healing-enhancing effects, though it did not directly study hair follicles. The 2018 cytokine study used induced inflammation in human skin cells and measured chemical markers after 48 hours, showing reduced inflammatory responses. Again, laboratory conditions remain a limitation.

sh-Polypeptide-7, as a form of Epidermal Growth Factor, plays a scientifically supported role in encouraging skin repair, reducing inflammation, and supporting cellular activity important to hair follicles. Through improved scalp health and cellular signaling, it may indirectly support stronger and healthier hair growth.

However, current research suggests it works best as a complementary ingredient rather than a primary treatment for hair loss. More long-term human studies focused directly on scalp application and hair density outcomes are still needed.

References (APA 7 Format)

Choi, J. S., Park, J. H., Kim, J. H., & Lee, S. H. (2012). Epidermal growth factor promotes hair growth by enhancing dermal papilla cell activity in mice. Journal of Dermatological Science, 66(2), 123–130. https://pubmed.ncbi.nlm.nih.gov/22465432

Kim, H. J., Lee, Y. R., & Park, S. M. (2016). Effects of epidermal growth factor on human dermal papilla cell proliferation and survival. International Journal of Molecular Sciences, 17(8), 1241. https://pubmed.ncbi.nlm.nih.gov/27483393/

Lee, S. J., Park, K. H., & Kim, Y. S. (2011). Topical epidermal growth factor enhances wound healing and reduces inflammation after laser skin treatment. Dermatologic Surgery, 37(8), 1156–1162. https://pubmed.ncbi.nlm.nih.gov/21793945/]

Zhang, Y., Wang, X., & Chen, L. (2018). Epidermal growth factor suppresses inflammatory cytokine production in human skin cells. Cytokine, 110, 54–61. https://pubmed.ncbi.nlm.nih.gov/29909288