Unlocking the Secrets of Anagen Follicles

Have you ever glanced at a mirror and wondered why some of your hair grows fast and some of it barely grows to your shoulders? The answer lies in the hair growth cycle, and its most crucial phase is known as anagen. 

Years of research have now shown that the state of your hairline is determined by the state of your anagen hair follicles in producing thick, healthy hair strands. 

In this article, we will discuss the complexity of these small powerhouses, their importance, and what can be done to optimise their performance. If you’ve ever dreamed of having healthier and more voluminous hair, a place to start is understanding the anagen phase.

What Exactly Are Anagen Follicles?

Anagen refers to the active growth phase in a hair follicle’s growth cycle. An anagen follicle refers to a hair follicle that is currently in the active growth stage, during which the hair shaft is growing longer. This stage is characterised by rapid cell division in the hair bulb and accounts for the vast majority of hair growth.

These tiny factories beneath your scalp are creating hair shaft after hair shaft as you go about your daily activities, progressively lengthening and thickening your hair. 

The Hair Growth Cycle

Hair doesn’t grow at random, but instead follows a set pattern. This cycle decides how long each hair grows, when it stops growing, and when it finally falls out. The hair growth cycle has three main phases: anagen, catagen, and telogen.

The anagen phase, during which hair grows, is crucial for achieving long, healthy hair. This stage can last anywhere from two to seven years, depending on factors such as your genes, health, and hair care regimen. Hair follicles are busy making new hair cells during this time, and hair grows about 1 centimetre every month. The longer the hair stays in this stage, the more it can grow.

The next phase is called catagen, and lasts only about two to three weeks. During this stage, hair growth stops as the follicles begin to shrink. This ‘maintenance’ phase is in preparation for the resting phase. 

The last phase is the telogen phase, which is also known as the resting phase. Typically, this phase lasts approximately two to three months. Hair does not grow during this period; instead, it remains affixed to the follicle until it eventually sheds, creating space for a new strand to grow.

Between 80 and 90 per cent of your scalp’s hairs should be in the anagen phase at any given time. 

Accordingly, only a small portion of your hair should be resting or transitioning, and the majority should be actively growing. A disturbance of this equilibrium can result in problems like hair thinning, slow growth, and strands prone to breakage. 

How Long Does the Anagen Phase Last?

The duration of the anagen phase can vary significantly among individuals, influenced by genetics, health, and lifestyle choices. Some fortunate people experience anagen phases that last as long as 7 years, whereas others may find theirs concluding in just 2-3 years.

If your anagen phase is 2 years and your hair grows at a rate of 1 cm per month, your hair could reach a maximum length of approximately 24 cm (around 9.5 inches). Conversely, if you have a 6-year anagen phase, you can grow your hair to a length of up to 72 cm (approximately 28 inches) long.

Anagen Phase Duration	Approximate Maximum Hair Length
2 years	24 cm (9.5 inches)
4 years	48 cm (19 inches)
6 years	72 cm (28 inches)

The FGF5 Connection: The Hair Growth Game Changer

A protein called FGF5 acts as a strict overseer, signalling to your hair follicles when to  exit the anagen phase and enter the catagen phase. It regulates the hair growth cycle, but what if we could prevent this switch to the resting phase? 

The large current research endeavour is focused on exploring how to inhibit the function of this vital protein. By stopping the actions of FGF5, it may be possible to extend the anagen phase and give hair more time to grow longer and stronger.

How to Tell if Your Hair is in the Anagen Phase

The following are unmistakable signs of healthy hair growth:

You’ll notice that your hair grows longer every month. When you touch it, it feels full and thick. Anagen hairs are firmly rooted, so a light tug won’t easily cause them to dislodge. You’ll also notice consistent growth throughout your scalp, not just in specific places.

What Influences Your Anagen Phase?

Several important factors influence the growth phase of hair follicles. Among them are:

1.  Nutrition: Hair follicles are some of the body’s most active cells, requiring a constant blood supply of nutrients to function correctly. Hair thinning and loss have been closely linked to deficiencies in essential nutrients, including protein, iron, zinc, and B vitamins such as biotin (B7) and vitamin B12. Many people underestimate the effectiveness of a well-rounded diet that includes leafy greens, lean proteins, whole grains, and healthy fats.

2.  Hormones: Hormones are potent hair cycle regulators. Dihydrotestosterone (DHT), derived from testosterone, plays a crucial role in the process of genetic hair loss, also known as androgenetic alopecia. 

Androgenetic alopecia can result from DHT’s ability to shrink hair follicles and cause them to exit the anagen phase prematurely, especially in genetically predisposed individuals. 

On the other hand, growth-promoting hormones like thyroid and oestrogen can lengthen the anagen phase. This explains why menopause or thyroid problems can cause abrupt hair loss, while high oestrogen levels during pregnancy frequently result in thicker hair. 

3.  Stress, particularly long-term physical or emotional stress, causes your body to produce more cortisol, a hormone that interferes with the cycle of hair growth. A condition known as telogen effluvium, in which a large number of hairs prematurely exit the anagen phase and fall out in clumps months later, can result from this alteration. In essence, stress tells your body to prioritise survival over appearance, which is why one of the first things it does is slow down hair growth. 

4.   Age is another inevitable factor – Hair follicles shrink, and the length of our anagen phase typically decreases with age, resulting in thinner and finer hair strands. Although everyone is affected differently by this normal aspect of ageing, it doesn’t mean you have no control over it. Making better dietary choices, adopting lifestyle changes, and taking hair loss medications can help slow this deterioration and preserve hair quality well into old age.

Anagen Effluvium: When Things Go Wrong

Anagen effluvium can occasionally arise from severe disruption of the anagen phase. This disorder interferes with the fast cell division in hair follicles, resulting in abrupt and severe hair loss.

This problem is known to be brought on by radiation therapy, chemotherapy, and some toxins. Anagen effluvium affects hair that is growing, unlike normal hair loss, which is why the effects can be so severe and distressing. Thankfully, hair typically grows back after the trigger is removed.

Treatments That Support Anagen Follicles

In reality, how can you maintain the health of your anagen follicles? These are the different tried-and-true methods:

• Medications: Hair loss medications like minoxidil and finasteride are routine treatments for hair loss. Finasteride works by blocking the harmful effects of DHT on hair follicles, and minoxidil helps to extend the anagen phase by increasing blood flow to the area. 
• Nutritional Support: Sometimes the simplest solutions are the most effective. Keeping on top of your general health and stress levels, and supplementing dietary deficiencies, are key to healthy hair. Biotin, iron, vitamin D, B12, and protein supplements can make a significant difference to hair growth. 
• Low-Level Laser Therapy (LLLT): LLLT utilises specific light wavelengths to stimulate cellular functions in hair follicles. Research indicates that it can prolong the anagen phase and enhance hair density. It’s akin to giving your follicles a gentle energy boost.
• Platelet-Rich Plasma (PRP): PRP involves injecting concentrated growth factors from your own blood into your scalp. These growth factors help prolong the anagen phase and improve hair thickness.

Common Myths About the Anagen Phase

Let’s debunk some common myths:

Myth: “Cutting your hair makes it grow faster”

Truth: Hair growth occurs at the follicular level, not at the tips. Trimming does not influence the anagen phase.

Myth: “Hair can only grow to a certain length”

Truth: The length your hair can reach is based on how long your anagen phase lasts, not on any set restriction.

Myth: “All hair loss is the same”

Truth: There are many different types of hair loss conditions, and they have other causes, symptoms and treatment plans. Understanding your type of hair loss is crucial to determining the proper management for it. 

Conclusion

Although several lifestyle changes, such as diet, stress management, and specific treatments, can strengthen your anagen follicles and promote healthier hair growth, lasting effects typically require expert guidance. If you suspect anagen effluvium, notice strange thinning patterns, have hair that won’t grow past a certain length, or experience abrupt or significant hair loss, it may be time to seek healthcare advice. 

At The Treatment Rooms London, our expert team of surgeons is committed to providing individualised, medically focused care. We are aware that each scalp is different and that early intervention often yields better outcomes. Whether you are considering a transplant or non-surgical options, our skilled professionals are ready to assist you at every step, quickly and openly.

Anagen Follicles FAQS

1. What is the anagen phase, and how long does it last?
The anagen phase is the active growth phase of the hair cycle when cells rapidly divide at the hair root, producing new hair. It typically lasts 2 to 7 years for scalp hair, with some sources saying 3 to 5 years, averaging around 6 inches (15 cm) per year. However, it can be as long as 7 years in specific individuals, depending on genetics and ethnicity.

2. What percentage of hair is in the anagen phase at any given time?
On a healthy scalp, 85–90% of hairs are in the anagen (growth) phase at any given time, with typically only 10–15% in the resting (telogen) phase and 1–3% in the transitional (catagen) phase.

3. Why doesn’t hair grow indefinitely?
Even during the anagen phase, hair is programmed to stop growing eventually. When follicles reach the end of their set cycle, they shrink and enter catagen. This preset limit prevents hair from growing endlessly and regulates regeneration.

4. How fast does hair grow during the anagen phase?
During the anagen (growth) phase, scalp hair typically grows at a rate of about 1 cm per month, or roughly 0.5 inches per month (~6 inches per year).