Hair Loss

What are the Main Causes of Hair Loss?

Key Takeaways
  • When asking “what causes hair loss, thinning, or baldness?”, the answer is complex. MPHL is an androgen-dependent, hereditary condition. ‘Hair loss’ is also misleading, since MPHL is actually the gradual transformation of normal hair follicles into smaller follicles with a shortened anagen phase (aka follicular miniaturization).
  • MPHL’s primary causes are related to genetic factors. It usually appears after puberty, which is associated with a dramatic increase in androgen production.
  • MPHL is related to dihydrotestosterone (DHT), an androgen that’s a potent metabolite of testosterone and has a great affinity for androgen receptors, and an 5-alpha reductase enzyme that mediates DHT’s conversion of testosterone in scalp hair follicles. Together, these elements lead to a gradual process known as follicular miniaturization.
  • There are a number of different types of hair loss, apart from MPHL, including: alopecia areata, traction alopecia, cicatricial (scarring) alopecias,  and trichotillomania.
  • Hair loss is treatable, but to achieve the best results, it’s a good idea to start treatment as early as possible. Even if hair regrowth isn’t possible, this can help slow/minimize hair loss.
  • If you’re interested in exploring hair loss treatments that may be helpful for you, complete a short online assessment, and one of our practitioners will typically get back to your request within 24 hours.

Hair loss is a frustrating, challenging condition that many people face as they get older. Some even begin to experience the symptoms of hair loss in their 20’s and 30’s, which can have a negative impact on their self-image and quality of life.

But what causes hair to fall out? This page will walk you through some of the most common causes of hair loss, and what you can do about it.

SIDE NOTE: It’s important to note that this page is devoted to information relating to Male Pattern Hair Loss (MPHL). If you’d like to learn more about hair loss in women, click here for more information.

If you’d like to talk to a healthcare practitioner about what hair loss medications may be available for you as part of your treatment plan, complete a short online assessment to get started today.

What Causes Hair Loss?

If you’ve been wondering “what causes hair loss or baldness?” This can be a challenging question to answer.

There are a few different factors that can explain what’s causing your hair to fall out. It’s vital to understand that Male Pattern Hair Loss (MPHL) is very common, and in many cases, there are treatments available that may be able to help slow this process.

Let’s start with the basics (or as basic as we can make it):

Pathogenesis: Androgens, Enzymes & Isoforms

MPHL is considered an androgen-dependent trait, which requires some kind of genetic predisposition, in order to occur.

Puberty is a phase everyone goes through that’s typically associated with a dramatic increase in androgens, which would explain why MPHL typically starts to develop after this stage. It would also explain why men with androgen-insensitivity syndrome don’t develop this condition.

The key androgen involved in both starting and supporting MPHL is dihydrotestosterone (DHT), which is a potent metabolite of testosterone and has a great affinity for androgen receptors.

There is an 5-alpha reductase enzyme that mediates DHT’s conversion of testosterone, but it exists in two isoforms (type 1 and type 2) that are located in scalp hair follicles (men that have mutations in their 5-alpha reductase type 2 gene don’t experience MPHL).

Differences between hormone metabolism and hormone receptors may also contribute to MPHL, since we know that young men with MPHL have higher 5-alpha reductase, as well as greater quantities of androgen receptors in balding areas versus non-balding scalp.

While we know more about hair loss now than ever before, there are more studies required to clarify what potential impacts exogenous androgens (i.e., anabolic steroids, testosterone supplementation, etc.), may have on the progression of MPHL.

Genetic Factors

As supported by familial studies, MPHL is considered hereditary. This means it’s often passed down genetically from parents to their children.

A study was conducted of 572 men, ages 16-91, found that men under 30 years of age that have a balding father are 5x more likely to experience MPHL, when compared to someone in the same age bracket whose father doesn’t have MPHL.

Another study that looked at 500 monozygotic twin men and 400 dizygotic twin men, between 25-36, found 80% of the variance in the extent of hair loss compared to genetic effects.

There are a number of chromosomal factors that have been identified as potentially contributing to the susceptibility of MPHL, including: (AR)/EDAR2 locus on the X chromosome, the PAX1/FOXA2 locus on chromosome 20p11, and the HDAC9 gene on chromosome 7p21.1.

Chromosome 3q26 may also be a contributing factor, and many other loci continue to be uncovered, adding to understanding of the genetic elements that play a role in MPHL.

Follicular Miniaturization

The idea of hair ‘loss’ as part of MPHL is actually a shortening of the anagen (growth) phase of your hair follicles, rather than hair completely disappearing in the affected areas.

This shortened anagen phase leads to shorter, thinner vellus hair shafts - a process that’s called follicular miniaturization. As more hair follicles begin to experience this miniaturization, hair coverage decreases progressively across the scalp.

In turn, this can appear as though you’re losing hair. So, instead of asking what can cause hair loss or thinning, we actually should be asking “what can trigger follicular miniaturization?”

Follicular miniaturization is caused by a hormone-driven process in your hair follicles’ dermal papilla. DHT binds with androgen receptors at the cellular level, which then activates the genes that are responsible for the gradual transformation of normal hair follicles into smaller follicles with shortened anagen phase.

Unfortunately, the exact mechanisms through genetic variants that cause follicular miniaturization to begin are unknown, but studies continue to be conducted.

This gradual transformation is associated with apoptosis of cells (cellular death) within the dermal papilla, as well as a shrinkage in the size of the dermal papilla. It’s believed that this could be a central part of the miniaturization process, since the size of your dermal papilla is directly related to the caliber of hair fiber that is produced.

Additional Elements That May Cause Hair Loss

It’s important to note that hormone-mediated pathogenic mechanisms have been the primary intensive focus of research, in relation to Male Pattern Hair Loss (MPHL).

However, there are a variety of other pathogenic mechanisms that could be relevant to what causes hair loss or baldness. These include: Wnt signals, prostaglandin D2 signals, prostaglandin F2-alpha signal, and Janus kinase (JAK) signals, among others.

There are some new treatments for androgenetic alopecia that have started to become prevalent in the healthcare industry, which are based on targeting some of these mechanisms that are under investigation.

If you’d like to talk to a healthcare practitioner at Felix about what hair loss medications may be beneficial for you as part of your treatment plan, just complete a short online assessment to get started.

The Different Types of Hair Loss

There are actually a few different types of hair loss, although they often present the same way - starting in the temporal scalp (around your ears), mid-frontal scalp (forehead), or vertex area (crown) of your scalp.

If your hair loss follows a different pattern from these three areas, it would be a good idea to talk to your healthcare practitioner, because it could be a sign that you have a skin disorder or a fungal infection.

Male Pattern Hair Loss (MPHL) needs to be distinguished individually from other causes of hair loss, although given how common it is, MPHL can coexist with other hair and scalp disorders. Let’s discuss some of the other different types of hair loss that you may experience:

Hair Maturation

This type of hair loss sees a slight recession of the hairline, which is a completely normal and hormonally-mediated occurrence that usually starts in early adulthood.

In men, this involves up to 2cm of posterior recession on the leading edge of your hairline, compared to its childhood position. It can also cause hair loss in the temporal region (around your ears), further adding to a change in the shape of your hairline.

This a limited recession overall compared to more extensive hair loss and vertex (crown) inclusion, which is a common sign of MPHL.

Alopecia Areata

Alopecia areata is an immune-mediated form of non-scarring hair loss. It most often appears as sudden hair loss in circular, discrete areas, but it can present as larger patches, or even loss of all scalp hair.

In some cases, the rare sisaipho (ophiasis inversus) pattern of hair loss, involving the frontal, temporal, and parietal scalp, can be mistaken for MPHL. This is because of how similarly it may appear upon initial diagnosis. However, unlike MPHL’s gradual nature, alopecia areata tends to occur rapidly, which is why scalp biopsies are sometimes useful for distinguishing the condition.

Traction Alopecia

This is a type of hair loss resulting from prolonged and/or repetitive tension on the hair follicles.

The location that you’ll experience hair loss correlates directly to the site of the traction. In most cases, the frontal and temporal scalp are most affected by traction alopecia.

For people with a history of traction-inducing hairstyles and hair loss in these affected areas will help support a diagnosis for this type of hair loss. When the diagnosis is unclear, your practitioner may request a biopsy to help clarify what is causing hair to fall out.

Cicatricial (Scarring) Alopecias

Cicatricial alopecias are a type of hair loss consistent with scarring (an absence of follicular ostia and vellus hairs), as well as a history of inflammatory signs or symptoms (i.e., pruritus, pain, inflamed papules, pustules, etc.).

In some cases, cicatricial alopecias are mistaken for MPHL, particularly when signs of inflammation at the affected areas are minimal or resolved.

A closer examination will often reveal evidence of previous inflammation and scarring, although in some cases, a biopsy may be requested to ensure an accurate diagnosis.

Trichotillomania

This is a psychiatric disorder, which is characterized by frequent, recurrent hair pulling.

People that have this type of hair loss often have uniquely shaped patches of alopecia, as well as hair shafts of varying lengths, due to multiple episodes of hair pulling.

Diagnosis for trichotillomania can usually be made by examining a patient’s history, although in some challenging cases, a biopsy may be requested to clarify.

Factors That Cause Hair Loss

As you can see there are a number of different answers for what can cause hair loss, but let’s review some of them:

  • Genetic factors
  • Immune-mediated elements
  • Age & natural changes in our body
  • Prolonged/repetitive hair tension
  • Long-term inflammation or scarring
  • Recurrent hair pulling

If you believe your hair loss is being caused by any of these elements, and you’d like to talk to a practitioner about what treatment options are available, just complete a short assessment to get started with Felix today!

Is Hair Loss Reversible?

In some cases, yes. Hair loss may be possible for some people, depending on what the cause of their hair loss or baldness is determined to be, as well as their individual response to treatments.

To achieve the best possible results, it’s a good idea to start treatments as early as possible. While you may not be able to regrow lost hair, there may be treatments available for you that can help slow the MPHL process.

What Can Be Done to Stop Hair Loss?

Get a diagnosis, so you can stop focusing on what’s causing your hair loss and start appropriate treatments. Do this as soon as you notice the first signs of hair loss.

Many people wait years to start their hair loss treatments, but for some people, it simply may not be possible to regrow lost hair.

There are a variety of treatments available that promote higher levels of success at slowing and minimizing hair loss, so that you can keep your remaining hair as long as possible.

When to Talk to a Healthcare Professional About Hair Loss

If you believe that you’re starting to experience hair thinning or hair loss, it’s a good idea to talk to a healthcare practitioner right away.

The earlier you start hair loss treatments, the more likely you are to achieve the best possible results, given your individual situation.

To get started today, just complete a short online assessment (at your convenience), and one of Felix’s practitioners will be happy to see whether there are any hair loss medications that may work for you as part of your treatment plan.

With Felix in your corner, you can take back control of your hairline and your quality of life, so that you can get back to living life on your terms - the way it should be.

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References

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