How Hair Follicles Communicate With Surrounding Skin

Hair follicles communicate with the surrounding skin through their specialised hair anatomy and chemical signals, helping regulate hair follicle function, growth, repair, and renewal. 

Evidence published in the Journal of Investigative Dermatology (Molecular Signatures and Signaling Interactions of the Hair Follicle Stem Cell Niche) shows that signalling interactions between hair follicle stem cells and neighbouring cells help regulate hair follicle function and the growth cycle.

What Is the Hair Follicle Function?

The hair follicle function is to produce, anchor, and maintain healthy hair while supporting the normal hair growth cycle. They are also active structures within the skin that help repair tissue, produce melanin for hair colour, and contribute to your sense of touch.

Each hair follicle works closely with the surrounding skin as part of a connected biological system. It also works with a sebaceous (oil) gland, which produces sebum to lubricate the hair and help maintain scalp health.

Your hair follicle has several important functions:

• Grow hair: Produces new hair through the normal hair growth cycle.

• Anchor the hair: Holds each hair strand securely within the skin.

• Support pigmentation: Produces melanin, the pigment that gives your hair its natural colour.

• Sense touch: Detects light touch through nerve endings surrounding the follicle.

• Protect the scalp: Works with the sebaceous gland to produce sebum that lubricates the hair and supports the skin barrier.

• Support skin repair: Contains stem cells that help repair skin and support tissue healing.

What Can Affect Hair Follicle Function?

Hair follicle function is affected by several internal and external factors that can disrupt the normal hair growth cycle and contribute to hair thinning or hair loss. The most common include: 

• Androgens and Dihydrotestosterone (DHT): Shrink hair follicles and shorten the growth phase.

• Thyroid hormones: Disrupt normal metabolism and trigger excessive hair shedding.

• Genetics: Determine your hair texture, natural colour, and susceptibility to pattern hair loss.

• Chronic stress: Pushes active hair follicles into a premature resting and shedding phase.

• Nutritional deficiencies: Reduce the nutrients needed to build healthy hair fibres.

• External damage: Harsh chemical treatments, high heat styling, and tight hairstyles can damage hair follicles or cause scarring that limits regrowth.

How Do Hair Follicles Send Signals to the Surrounding Skin?

Hair follicles send signals to the surrounding skin through follicle signaling: a network of chemical signals, neurotransmitters, growth factors, and direct communication with nearby cells. These signals help regulate hair follicle biology, tissue repair, sensation, and healthy hair growth. 

Which Cells Do Hair Follicles Communicate With? 

Hair follicles communicate with several specialised cells that regulate hair follicle function, tissue repair, sensation, and the hair growth cycle. These include:

• Dermal papilla cells: Act as the follicle's control centre by releasing signals that regulate hair growth.

• Keratinocytes: Build the hair shaft and help maintain the normal hair growth cycle.

• Stem cells: Reside in the follicle bulge and exchange signals with nearby fat cells and the arrector pili muscle to support follicle regeneration.

• Immune cells: Release chemical signals that protect the hair follicle and regulate the hair growth cycle.

• Sensory nerve cells: Wrap around the hair follicle to detect hair movement and light touch.

• Arrector pili muscle: Contracts in response to nerve signals, causing the hair to stand upright and produce goosebumps.

What Signals Do Hair Follicles Send?

Hair follicles release several chemical and developmental signals that regulate hair growth, sensation, and tissue repair, including: 

• Serotonin and histamine: Help transmit local touch-related signals between hair follicles and nearby sensory nerve cells. 

• Adenosine Triphosphate (ATP): Helps transmit light-touch signals from the hair follicle to the nervous system.

• Wnt signalling: Helps initiate the hair growth cycle. 

• Bone Morphogenetic Protein (BMP): Regulates the balance between hair growth and rest. 

• Sonic Hedgehog (Shh): Supports normal hair follicle development and regeneration. 

Why Is Hair Follicle Biology Important for Hair Growth?

Hair follicle biology is important because it controls how hair follicles grow, regenerate, repair themselves, and respond to changes in the surrounding skin. 

These processes are regulated by specialised signalling pathways that determine when hair follicles grow, rest, or regenerate. The following table summarises the main signalling pathways involved in healthy hair growth. 

Why this matters: These signalling pathways work together to regulate when hair follicles grow, rest, regenerate, and repair. When this communication is disrupted by factors such as genetics, hormones, inflammation, or stress, normal hair growth can also be affected. 

What Happens When Hair Follicle Communication Is Disrupted?

When hair follicle communication is disrupted, hair follicles cannot coordinate normal growth, repair, and regeneration. 

As a result, the hair growth cycle may become unbalanced, increasing the risk of hair thinning, excessive shedding, and poor scalp health. Common effects include:

• Hair loss: Hair follicles may enter the resting (telogen) phase too early, leading to increased hair shedding.

• Inflammation: Ongoing inflammation can damage the follicle's surrounding environment and interfere with normal signalling.

• Poor scalp health: An unhealthy scalp can weaken communication between hair follicles and nearby skin cells.

• Ageing: Natural ageing slows cellular signalling, reducing the hair follicle's ability to regenerate.

• Scarring alopecia: Permanent damage to hair follicles disrupts communication and prevents natural hair regrowth.

How Can You Support Healthy Hair Follicle Function?

You can support healthy hair follicle function by following healthy lifestyle habits that promote normal hair growth and maintain good scalp health. To help keep your hair follicles healthy:

• Eat a balanced diet: Include enough protein, iron, zinc, omega-3 fats, and vitamins D and B to support healthy hair growth.

• Maintain good scalp health: Use a gentle shampoo, massage your scalp regularly, and avoid excessive heat styling.

• Manage stress: Reducing chronic stress can help maintain a healthy hair growth cycle.

• Correct nutritional deficiencies: Work with a healthcare professional to identify and treat deficiencies that may affect hair growth.

• Seek medical advice: Consult a dermatologist if you experience persistent, excessive, or sudden hair loss.

Traya's Perspective on Hair Follicle Function

Healthy hair follicle function depends on maintaining good scalp health and addressing the underlying causes of hair loss. While a balanced diet, gentle scalp care, and stress management can support normal hair growth, they may not be enough to treat medical hair loss.

At Traya, we believe in improving long-term hair health by identifying and treating the root cause, rather than relying on temporary solutions alone.

If you're experiencing persistent hair thinning, excessive hair shedding, or slow hair regrowth, the Traya Hair Test can help identify the factors affecting your hair follicle function and recommend a personalised treatment plan based on your hair and health profile.

Frequently Asked Questions

1. How far under the skin is a hair follicle?

Hair follicles extend from the skin surface into the dermis and sometimes the subcutaneous layer, depending on the body area and hair type. 

2. How can you stimulate your hair follicles?

Support healthy hair follicles with good nutrition, scalp care, stress management, and appropriate medical treatment if an underlying hair loss condition is present. 

3. Can you feel a hair follicle?

No. You cannot feel the hair follicle itself, but the nerves surrounding it detect hair movement, touch, and pressure. 

4. Do damaged hair follicles grow back?

Healthy but dormant hair follicles may recover, while permanently scarred or destroyed follicles cannot naturally regrow hair. 

5. Why are hair follicles important for healthy hair growth?

Hair follicles produce, anchor, and regenerate hair while coordinating signals that regulate the normal hair growth cycle and scalp health. 

References 

• Ghuwalewala S, Cao J, Rezza A, Rangl M, Kwiatkowski A, Brown A, Grisanti L, Heitman N, Schober M, Wang Z, Ma'ayan A, Almet AA, Plikus MV, Rendl M. (2026). Molecular Signatures and Signaling Interactions of the Hair Follicle Stem Cell Niche. Journal of Investigative Dermatology. 
• Imperial College London. (2023). Hidden Way for Us to Feel Touch Uncovered by Imperial Researchers. Imperial College London News. 
• Li KN, Tumbar T. (2021). Hair Follicle Stem Cells as a Skin-Organizing Signaling Center During Adult Homeostasis. The EMBO Journal. 
• Agramunt J, Parke B, Mena S, et al. (2023). Mechanical Stimulation of Human Hair Follicle Outer Root Sheath Cultures Activates Adjacent Sensory Neurons. Science Advances. 
• Schneider MR, Schmidt-Ullrich R, Paus R. (2009). The Hair Follicle as a Dynamic Miniorgan. Current Biology. 

Read More Blogs

Rosemary Oil for Hair Elasticity and Strand Strength

When your hair snaps instead of stretching, it’s often crying out for better nourishmen...

Patch Testing Jojoba Oil for Allergies

Jojaba oil feels light, smooth, and almost weightless on the skin - but even natural oi...

Finasteride for Maintaining Transplanted Hair Results

Hair transplant success doesn’t end in the OT — it begins thereIf you’ve undergone a ha...

Conditioner Before Swimming: Does It Help?

That tight, straw-like feeling after a swim is something most of us know too well. Yes,...

30-Day Onion Juice Hair Challenge Results

The smell hits you first. Sharp, raw, unmistakable. Then comes the question everyone as...