Alopecia androgenetica (hormonal hair loss)
Alopecia androgenetica is a genetically influenced, hormonally mediated form of non-scarring hair loss characterised by progressive follicular miniaturisation and pattern-based thinning.
Understanding alopecia androgenetica
Alopecia androgenetica is a non-scarring form of hair loss driven by genetic sensitivity of specific hair follicles to dihydrotestosterone (DHT). Over time, affected follicles gradually miniaturise, producing thinner and shorter hairs with each growth cycle.
Because this process develops slowly and follows recognisable patterns, early changes are often subtle. Understanding the biological mechanism is essential for distinguishing pattern-based hair thinning from temporary or reactive forms of hair loss.
What Is alopecia androgenetica?
Alopecia androgenetica is the most common form of progressive hair loss in both men and women and is widely known as male pattern hair loss or female pattern hair loss.
It is driven by hormonal sensitivity at the hair follicle level and develops gradually over time.
Importantly, it is not caused by poor hair care, shampoo use, stress alone, or nutritional deficiency.
The condition is rooted in how specific hair follicles respond to normal levels of androgens, particularly dihydrotestosterone (DHT).
What alopecia androgenetica is - and is NOT
Alopecia androgenetica is:
- A biologically driven condition
- Progressive if left unaddressed
- Pattern-based rather than random
Alopecia androgenetica is NOT:
- A sudden shedding disorder
- Caused by stress alone
- A sign of poor health
This distinction is essential, as alopecia androgenetica is frequently confused with temporary or reactive forms of hair loss.
Are you not sure if this applies to you?
In hereditary hair thinning, long-term, targeted support is often part of a structured approach. Learn more about TRIX Basic Alpha.
How does alopecia androgenetica develop?
Alopecia androgenetica develops as a result of a combination of genetic predisposition and increased sensitivity of certain hair follicles to hormonal signals. This does not involve a hormonal disorder or abnormal hormone levels, but rather an inherited response of specific hair follicles.
This sensitivity varies between individuals and between different areas of the scalp, which explains why alopecia androgenetica develops according to recognisable patterns.
The role of dihydrotestosterone (DHT)
An important factor in alopecia androgenetica is dihydrotestosterone (DHT), a biologically active derivative of the hormone testosterone. DHT plays a role in normal physiological processes, but in individuals with a predisposition to alopecia androgenetica, certain hair follicles respond more strongly to its presence.
As a result of this increased sensitivity, the hair growth cycle of the affected follicles changes. The growth phase of the hair becomes shorter, meaning the hair has less time to grow before it sheds.
Miniaturisation of hair follicles
As a consequence of these changes in the hair growth cycle, sensitive hair follicles undergo a process known as miniaturisation. During successive growth cycles, these follicles produce:
- thinner hair
- shorter hair
- hair with a reduced lifespan
Over time, the follicle may shrink to such an extent that little to no visible hair is produced. This process occurs gradually and explains why alopecia androgenetica typically becomes clearly noticeable only after several years.
Genetic sensitivity determines the pattern
Not all hair follicles respond to DHT in the same way. Genetic sensitivity varies across different regions of the scalp, which explains why alopecia androgenetica follows characteristic patterns.
In men, this most commonly affects the temples and the crown, whereas in women it usually presents as diffuse thinning around the central parting.
Why hormone levels are usually normal
It is important to emphasise that alopecia androgenetica is, in most cases, not caused by elevated hormone levels. Testosterone and DHT levels are generally within the normal range.
The difference lies in how the hair follicle responds to these hormones, not in the overall amount of hormone present in the body.
Why the process is not reversible, but may be influenced
Because follicular miniaturisation is a structural process, complete recovery of hair follicle activity that has already been lost is usually not possible. However, in some cases, the progression of alopecia androgenetica may be slowed or stabilised when the process is recognised at an early stage.
For this reason, understanding the type of hair loss involved and identifying when the process is active are of key importance.
How alopecia androgenetica differs from other types of hair loss
Although alopecia androgenetica is the most common form of progressive hair thinning, not all hair loss follows the same biological mechanism.
Unlike telogen effluvium, which causes sudden diffuse shedding often triggered by stress, illness, or hormonal shifts, alopecia androgenetica develops gradually and follows recognisable patterns.
In contrast to alopecia areata, an autoimmune condition that typically presents with well-defined round bald patches, androgenetic alopecia causes progressive thinning without sharply demarcated areas of hair loss.
Unlike scarring conditions such as frontotemporal fibrosing alopecia, the hair follicle structure remains intact in alopecia androgenetica, meaning the process is driven by miniaturisation rather than permanent follicular destruction.
For a broader overview, see the full guide to types of hair loss and medical classification.
How alopecia androgenetica develops over time
Alopecia Androgenetica develops gradually over many years. The changes occur at the level of individual hair follicles and often become noticeable only after a significant reduction in hair density has already taken place. To understand this process, it is important to first understand the normal hair growth cycle.
The normal hair growth cycle
Each hair follicle repeatedly goes through a cycle consisting of three phases:
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Anagen (growth phase)
The hair grows actively. In healthy hair follicles, this phase can last several years.
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Catagen (transition phase)
Hair growth slows and the follicle prepares for a resting period.
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Telogen (resting and shedding phase)
The hair is eventually shed and replaced by a new growing hair.
Under normal conditions, hair follicles cycle independently of one another, which helps maintain overall hair density.
What changes in alopecia androgenetica
In alopecia androgenetica, certain hair follicles respond differently to hormonal signals. As a result, the hair growth cycle gradually changes:
- the growth phase becomes progressively shorter
- the hair grows thinner and for a shorter length of time
- each successive growth cycle produces a weaker hair than the previous one
This process is known as follicular miniaturisation and does not occur suddenly, but accumulates over multiple hair growth cycles.
Why progression is slow but cumulative
Because the changes per hair growth cycle are relatively small, alopecia androgenetica progresses slowly. However, each cycle contributes to further weakening of the hair follicle. Over months and years, this cumulative effect leads to visibly thinner hair and reduced hair density.
Why early stages are often missed
In the early stages, hair is often still present, but its quality changes subtly. As a result, alopecia androgenetica is frequently not recognised immediately. At this stage:
- hair distribution may still appear acceptable
- hair becomes more difficult to style
- density gradually decreases rather than disappearing suddenly
Only when follicular miniaturisation has progressed further does hair loss become clearly noticeable for most people.
Alopecia androgenetica in men and women
Although alopecia androgenetica is driven by similar biological mechanisms in both sexes, its clinical presentation differs between men and women. These differences are primarily related to genetic sensitivity patterns of hair follicles across different areas of the scalp.
Understanding these distinctions helps explain why hair loss can look very different from one person to another, even when the underlying condition is the same.
Alopecia androgenetica in men
In men, alopecia androgenetica typically follows well-defined and recognisable patterns. Hair follicles in specific areas of the scalp are more sensitive to hormonal signals, leading to progressive thinning over time.
Common characteristics include:
- recession at the temples
- thinning at the crown (vertex)
- gradual enlargement of affected areas
These changes often begin in early adulthood and may progress steadily over many years. The pattern of hair loss is usually symmetrical and follows predictable stages.
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Receding hairline at the temples
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Thinning at the crown (vertex)
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The affected areas gradually expand and may connect over time
Alopecia androgenetica in women
In women, alopecia androgenetica generally presents differently. Rather than clear recession or bald areas, hair loss is more often diffuse and less sharply defined.
Typical features include:
- gradual thinning across the top of the scalp
- widening of the central parting
- preservation of the frontal hairline in most cases
Because the hair loss is spread more evenly, early stages may be less noticeable and are often mistaken for general hair thinning or age-related changes.
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Progressive widening of the central part line
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Reduced hair density around the crown and mid-scalp
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Preservation of the frontal hairline in most cases
Why patterns differ between men and women
The differences in presentation are not caused by different hormone levels, but by variations in genetic sensitivity of hair follicles across the scalp. These sensitivity patterns are influenced by hereditary factors and differ between men and women.
As a result, the same underlying process can lead to clearly visible baldness in men, while producing diffuse thinning in women.
Age and progression
The onset and rate of progression of alopecia androgenetica vary widely. In both men and women, the condition may begin at different ages and progress at different speeds. While some individuals notice changes early in adulthood, others may experience very gradual progression over decades.
Age influences how noticeable the condition becomes, but it does not determine whether alopecia androgenetica will occur.
Why recognition can be more difficult in women
Because hair loss in women is often diffuse and develops gradually, alopecia androgenetica may remain unrecognised for a long time. Hair density can decrease significantly before visible changes become obvious, especially when styling compensates for early thinning.
For this reason, understanding sex-specific patterns is essential when assessing hair loss.
Distinguishing alopecia androgenetica from other forms of hair loss
While alopecia androgenetica follows characteristic biological and pattern-based features, clinical evaluation remains important to distinguish it from other hair loss disorders that may present with overlapping early symptoms.
Alopecia androgenetica
Alopecia androgenetica is a chronic, progressive form of hair loss driven by genetic sensitivity of hair follicles to hormonal signals. It typically follows recognisable patterns and develops gradually over time.
Key characteristics include:
- gradual onset and slow progression
- pattern-based thinning rather than random shedding
- progressive miniaturisation of affected follicles
- long-term reduction in hair density and thickness
Without intervention, the process generally continues over many years.
Telogen effluvium
Telogen effluvium is a form of diffuse hair shedding that occurs when a large number of hair follicles prematurely enter the resting (telogen) phase of the hair growth cycle. This condition is usually triggered by a temporary stressor.
Common triggers include:
- physical or emotional stress
- illness or surgery
- hormonal changes
- nutritional deficiencies
Hair loss in telogen effluvium is typically sudden and widespread. In many cases, it is temporary, with regrowth occurring once the underlying trigger resolves.
Alopecia areata
Alopecia areata is an autoimmune condition in which the immune system mistakenly targets hair follicles, leading to sudden, well-defined patches of hair loss.
Typical features include:
- round or oval bald patches
- sudden onset
- possible involvement of eyebrows or body hair
The course of alopecia areata is unpredictable and differs fundamentally from alopecia androgenetica in both mechanism and pattern.
Frontotemporal fibrosing alopecia (FFA)
Frontotemporal fibrosing alopecia is a form of scarring alopecia characterised by progressive recession of the frontal hairline and, in many cases, eyebrow thinning. Unlike androgenetic alopecia, FFA involves inflammatory processes that may lead to permanent follicular destruction.
Key distinguishing features include:
- band-like frontal hairline recession
- possible redness or scaling at the hairline
- eyebrow loss
- evidence of scarring on clinical examination
Because FFA is a scarring alopecia, early identification is particularly important, as follicular destruction may become irreversible.
Why correct differentiation matters
Although these conditions can all result in visible hair loss, their causes, biological mechanisms, progression patterns, and long-term outlook differ substantially.
- Alopecia androgenetica is typically chronic and progressive, whereas telogen effluvium is often temporary and alopecia areata follows an autoimmune course.
- Telogen effluvium is often temporary.
- Alopecia areata follows an autoimmune course.
- Frontotemporal fibrosing alopecia involves inflammatory scarring and may result in permanent follicular loss.
Because symptoms may overlap, especially in early stages, misinterpretation is common. A structured assessment is often needed to clarify which form of hair loss is most likely. For a broader medical overview of hair loss classifications and underlying mechanisms, see our Hair Loss Conditions overview.
Gaining insight into your type of hair loss
Understanding whether hair loss is pattern-based, diffuse, patch-like, or associated with inflammatory changes is an important first step in identifying the underlying mechanism. This distinction helps guide realistic expectations and appropriate next steps.
Read more about:
- Telogen effluvium (temporary hair shedding triggered by stress or hormonal changes)
- Alopecia areata (patchy autoimmune hair loss)
- Frontotemporal fibrosing alopecia (scarring frontal hairline recession)
How alopecia androgenetica is identified in practice
Alopecia androgenetica is not identified based on a single symptom or observation.
In clinical practice, assessment is based on a combination of pattern, timing, and follicular behavior, evaluated together rather than in isolation.
This structured approach helps distinguish alopecia androgenetica from temporary or reactive forms of hair loss and reduces the risk of misclassification.
No single sign is decisive
Hair loss can present in many ways, and similar symptoms may have different underlying causes.
For this reason, clinicians do not rely on shedding alone, visible thinning alone, or family history alone to identify alopecia androgenetica.
Instead, diagnosis emerges from the overall pattern and progression over time.
Key elements clinicians consider
When assessing for alopecia androgenetica, clinicians typically evaluate the following. No single factor is sufficient on its own. Assessment is cumulative, integrating multiple observations.
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Pattern and distribution
Whether thinning follows characteristic androgen-sensitive areas rather than occurring randomly across the scalp.
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Onset and progression
Gradual change over months or years, rather than sudden or episodic hair loss.
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Hair shaft variability
The presence of thick, terminal hairs alongside thinner, weaker hairs in the same area, a sign of progressive follicular miniaturization.
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Stability of the frontal hairline
Particularly relevant in women, where preservation of the frontal hairline supports androgenetic rather than scarring or autoimmune causes.
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Scalp condition
Absence of scarring, inflammation or sharply defined patches.
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Contextual factors
Age, hormonal status and other background factors that influence likelihood and presentation.
Dermatoscopy often reveals progressive follicular miniaturisation with variation in hair shaft diameter, a hallmark dermatoscopic feature of alopecia androgenetica.
If you are unsure how these clinical criteria apply to your situation, the next step is structured assessment based on pattern, timing, and risk factors rather than guesswork.
The role of long-term support and the TRIX Hair Check
Alopecia androgenetica is a chronic condition that develops over time. Because the underlying genetic sensitivity of hair follicles cannot be altered, the focus is not on curing the condition, but on understanding its progression and supporting hair follicle function over the long term.
Gaining clarity about the type of hair loss involved is an essential first step. Without understanding whether hair loss is pattern-based, diffuse, or patch-like, it is difficult to determine which next steps are appropriate.
Why early insight matters
In the early stages of alopecia androgenetica, many hair follicles are often still active, even though subtle changes in hair quality and density may already be occurring. As the condition progresses, follicular activity can decline further.
Recognising alopecia androgenetica at an early stage helps establish realistic expectations and supports informed decision-making around long-term support.
The value of a structured assessment
Because different forms of hair loss can present with overlapping features, a structured assessment is often necessary. Such an evaluation considers factors including hair loss pattern, onset, progression over time, and individual characteristics.
The TRIX Hair Check is designed to guide users through a short, structured assessment to help identify which type of hair loss is most likely and which form of support may be relevant.
Long-term support in alopecia androgenetica
Support strategies for alopecia androgenetica typically focus on maintaining hair follicle function and scalp condition over time. These approaches are not intended to reverse the condition, but to align with its long-term and progressive nature.
TRIX Basic Alpha is formulated as daily nutritional support for individuals with alopecia androgenetica and is intended to be used as part of a broader, long-term approach.
Gaining clarity about your situation
Understanding the type and pattern of hair loss involved can provide clarity and direction. A structured assessment can help distinguish alopecia androgenetica from other forms of hair loss and support informed next steps.
Based on 20+ years of dermatological expertise
Frequently Asked Questions about alopecia androgenetica (hormonal hair loss)
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What is alopecia androgenetica?
Alopecia androgenetica is a chronic, genetically influenced form of hair loss in which certain hair follicles are sensitive to hormonal signals. This sensitivity leads to gradual thinning in recognisable patterns.
Is alopecia androgenetica the same as hereditary hair loss?
Yes. Alopecia androgenetica is commonly referred to as hereditary or hormonal hair loss. It is linked to inherited follicular sensitivity to androgens, particularly DHT.
What is the difference between male and female pattern hair loss?
The underlying mechanism is similar, but the pattern differs. In men it often starts at the temples and crown; in women it more commonly presents as diffuse thinning around the central parting with relative preservation of the frontal hairline.
Is alopecia androgenetica caused by stress?
No. Alopecia androgenetica is not caused by stress. Stress can trigger telogen effluvium, a temporary diffuse shedding pattern that may be confused with androgenetic hair loss.
Are hormone levels abnormal in alopecia androgenetica?
Usually not. Testosterone and DHT levels are generally within normal ranges. The difference lies in how genetically sensitive follicles respond to these hormones.
What role does DHT play in alopecia androgenetica?
Dihydrotestosterone (DHT) affects genetically sensitive follicles and can drive progressive miniaturisation. Over time the growth phase shortens and hairs become thinner and shorter.
What is follicular miniaturisation?
Miniaturisation is the process in which a follicle gradually shrinks over multiple growth cycles and produces progressively thinner, shorter hairs. Eventually it may produce little to no visible hair.
When does alopecia androgenetica usually begin?
It may begin in early adulthood, but onset varies widely. In some individuals progression is slow and becomes noticeable over many years or decades.
How can I recognise alopecia androgenetica early?
Early on, hair is often still present but quality changes: strands become finer, styling becomes harder, and density decreases gradually. In men this may start at temples or crown; in women around the central parting.
What is the difference between alopecia androgenetica and telogen effluvium?
Alopecia androgenetica is pattern-based and progressive with miniaturisation. Telogen effluvium typically causes sudden, diffuse shedding after a trigger (such as illness, stress, surgery, or hormonal change) and is often temporary.
What is the difference between alopecia androgenetica and alopecia areata?
Alopecia androgenetica causes gradual thinning without sharply defined bald patches. Alopecia areata is an autoimmune condition that typically presents with sudden, well-defined round or oval patches and a variable course.
How does alopecia androgenetica differ from scarring alopecia (such as FFA)?
In alopecia androgenetica the follicle structure remains intact and the process is driven by miniaturisation. In scarring alopecia there is inflammatory damage with scarring, which can permanently destroy follicles and prevent regrowth in affected areas.
Is alopecia androgenetica reversible?
Complete recovery of follicles that have undergone advanced miniaturisation is usually not possible. Early recognition can help guide realistic expectations and long-term support decisions.
Can shampoo, hair care, or styling cause alopecia androgenetica?
No. Alopecia androgenetica is not caused by shampoo, styling, or poor hair care. It is a genetically and hormonally influenced process at the follicle level.
How is alopecia androgenetica assessed clinically?
Assessment considers pattern, timing, and follicular features. Dermoscopy often shows variation in hair shaft diameter and signs of progressive miniaturisation, which are characteristic of androgenetic alopecia.
When is medical evaluation recommended for hair loss?
Medical evaluation is recommended if the pattern is unclear, if shedding is sudden or unusually severe, if patchy bald spots develop, or if there are scalp symptoms such as pain, redness, scaling, or signs of inflammation.
This page provides general educational information and does not replace medical diagnosis or treatment. For personalized medical advice, consult a qualified healthcare professional.
