Hair Loss: Types and Causes

Written by Our Editorial Team
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Hair plays a significant role in how we appear to the world. Shedding, thinning, and balding are all major issues that affect people of all ages and genders. More than just a physical concern, the conditions can also lead to mental and emotional struggles. 

While it is critical to identify the cause of hair loss to ensure effective resolutions, you can also dispel many misbeliefs and prevent additional distress through a thorough understanding of different types of hair loss.

There are two main types of hair loss: non-scarring and scarring. Some non-scarring types may show improvement, while scarring types are generally considered long-lasting. In this blog, you will go through the three most common kinds of hair loss, namely Androgenetic Alopecia (pattern hair loss), Telogen Effluvium, and Anagen Effluvium, to some less common ones, together with their characteristics and causes.

1. Androgenetic Alopecia (AGA) or Pattern Hair Loss

androgenetic alopecia type in men before and after

Androgenetic Hair Loss is also widely known as Pattern Hair Loss. Besides, you can also find this type of hair loss under the name hereditary or genetic hair loss. Androgenetic Alopecia has its name after androgen, a hormone that plays an important role in growth and reproduction. It is one of the most common causes of hair shedding in both men and women. 

Male pattern hair loss (FPHL)

MPHL follows a relatively predictable and familiar pattern, the shape “M”. Hair shedding starts from above both temples, then across the top, and finally toward the crown of the head. Over time, hair becomes thinner near the top of the head, creating partial or complete baldness afterwards. MPHL is predominantly due to genetic factors. Research indicates that males can inherit such hair loss conditions from either side of the family.

In males, besides playing a critical role in normal sexual development before birth and during adolescence, androgens contribute to the regulation of hair growth. Testosterone is the major circulating androgen in men.

However, dihydrotestosterone (DHT), the 5α-reduced metabolite of testosterone, is one hormone that is widely known for driving hair loss. When more testosterone converts to DHT via 5α-reductase, the extent of hair loss will be greater.

In general, your genes impact how sensitive your hair follicles are to DHT, which can shorten the hair growth phase, increase the telogen phase, and lead to follicular miniaturization.

Over time, new hairs cannot peek through the scalp surface, as the follicle shrinks. Furthermore, telogen hairs do not anchor well to the scalp, making it easier to fall out. Finally, hair balding appears. 

The frequency and level of MPHL increase with age. According to research, up to 30% of white men see signs of genetic hair loss by the age of 30 years, up to 50% by 50 years, and 80% by 70 years. 

Besides the strong connection with your genes, MPHL has been linked with several other medical conditions incorporating diseases related to the heart and prostate, such as high blood pressure, diabetes, obesity, or prostate cancer.

Female pattern hair loss (FPHL)

In females, pattern hair loss tends to occur throughout the scalp (diffuse thinning), starting at their central line and then causing the line to be broader with time, while hair at the temples may also recede.

Depending on its extent, females can see either a small amount of thinning at the middle line and the area around it or a see-through area at the top of the scalp along with thinning all over the head. However, FPHL induces hair thinning but does not often result in total baldness as in men. 

Similar to MPHL, FPHL is hereditary. It is passed down from parents to their children, with different genes engaged. But according to recent studies, the influences of genetics and the androgen hormones are not as strong as men.

FPHL usually begins at about the age of 30. The issue often gets more noticeable around the age of 40. By the age of 50, at least a quarter of women experience some degree of hair thinning.

FPHL is more common and may become significantly severe after menopause. To help hair grow faster and stay longer, females need oestrogen and progesterone. During menopause, these hormones diminish. As a result, hairs grow more slowly and become much thinner. 

FPHL also happens when the risk of polycystic ovary syndrome increases. This risk is characterized by the imbalance of hormones, leading to irregular menstruation, acne, excess hair fall, and weight gain.

2. Telogen Effluvium

hair loss in men

As seen in its name, telogen effluvium is associated with the telogen phase of the hair growth cycle, and it is also a non-scarring hair loss type. It causes the hair cycle to enter the telogen phase prematurely, thus a quick end to the anagen phase.

Telogen effluvium (TE) is often temporary and more common in women. It causes hair thinning or large amounts of hair shed. Thus it can be noticed when the ponytail becomes thinner, or the gap in the hair central part line expands. 
The impact of this type of hair loss can vary based on the condition and duration of factors contributing to the issue. Besides, unexplained changes through your body could also be responsible for the different levels of telogen effluvium.

Various factors are thought to contribute to Telogen Effluvium. They include childbirth, severe illness (e.g., fever), surgical operation, psychological stress, weight loss, dietary alterations, malnutrition (e.g., iron deficiency), drugs (e.g., antibiotics), endocrine disorders (e.g., hypothyroidism, hyperthyroidism), discontinuing contraceptive pills, a skin disease affecting the scalp (eg, erythroderma), and so forth.

3. Anagen effluvium

a guy losing hair due to anagen effluvium

This is a form of hair shedding that leaves no scarring effect. It happens similarly and equally among men and women across the world. In anagen effluvium, the hair shaft is tapered, narrowed, altered, or broken off.

This disorder is strongly associated with chemotherapy, a primary, cancer treatment. Chemotherapy may have side effects that can affect hair health, potentially causing damage to the hair bulb and leading to changes in the hair shaft. The condition of hair loss varies between patients, but it is abnormal to have complete hair loss within the first 2 to 3 months of the chemotherapy. 
Once chemotherapy started, anagen effluvium occurs within days to a few weeks. In many cases, some level of hair regrowth may be observed within 3 to 6 months after completing the therapy.

4. Other types of hair loss

woman hair flying in the wind


Trichotillomania is well-known as the most common cause of childhood alopecia. The common age of onset is eight years in boys and twelve years in girls. 

This condition is also called the hair-pulling disorder. It is a mental disorder that involves repeated, unavoidable urges to pull out hairs from the scalp, eyebrows, or other areas, despite trying to stop. For people who get this disease, hair pulling can help them relieve tension or distress. However, some do that unintentionally, such as when they feel bored, reading, or watching TV.
Although hair can be pulled from all body parts when done to the scalp, it can create bizarre patterns with incomplete areas of the clearing. In some cases, it might cause areas with red and infected swelling.
The cause of trichotillomania is unclear. But like many complex disorders together with their psychological nature, it probably results from a connection between genetic and environmental factors.

Tinea Capitis

This type of hair loss happens due to a fungal infection of the scalp, such as Microsporum or Trichophyton species of dermatophytes. Tinea capitis is common in prepubertal patients. Its most serious forms are abscesses with overlying hair loss, which causes widespread hair loss, and increased fragility of hairs.

Alopecia Areata

Alopecia areata is likely a secondary reaction of the human immune system related to the loss of antibody, T-cell and cytokine-mediated. In other words, it develops when the body’s immune system attacks hair follicles. 

It causes complete hair loss in certain areas of your scalp, then it might spread out afterward and often results in patchy bald spots. This disease usually happens with 0.1 to 0.2% of the population for both genders equally. 

Traction Alopecia

This type of hair loss happens mostly in the frontal and temporal areas and is related to grooming styles, for example, tight braids (especially “cornrows”) or tight ponytails. These hairstyles induce high tension and breakage in the outermost hair. Switching to looser hairstyles may be helpful in reducing the likelihood of experiencing traction alopecia.

Cicatricial Alopecia

This is a general term for most scarring forms of hair loss. It triggers permanent hair loss by destroying hair follicles completely without regrowth. There are some possibilities for such conditions. One possibility could be related to issues at the base of the hair follicles. The failure might be a consequence of inflammatory processes or autoimmune, neoplastic, developmental, and hereditary disorders. Another reason comes from skin diseases such as dissecting cellulitis, lichen planopilaris, and folliculitis decalvans.


mature hairline vs balding comparison

Hair loss can occur in many different ways, depending on the triggers or root causes. The three main types of hair loss in adults are androgenetic alopecia, telogen effluvium, and anagen effluvium. These types are caused mainly by genes (mainly for men), hormones (mainly for women), stressors that disrupt the anagen phase, or chemotherapy.

Besides, there are other different types of hair loss coming from a variety of triggers. Such hair thinning conditions can happen in diverse manners: gradually or suddenly; in various stages of life, from childhood, adolescence, and maturity.



The information we provide is not intended to mitigate, prevent, treat, cure or diagnose any disease or condition. If you have any concerns about your health, please consult your doctor.


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