Hair loss or alopecia might not be a life-threatening condition but it can cause psychological distress to some people. Understanding and choosing the best management and treatment options available to a particular individual first requires understanding the different types of hair loss and their respective causes.
7 Types of Hair Loss and How to Spot Them
Take note that hair loss can occur in different forms and have various causes. Some of these causes are genetic and hormonal while others involve certain lifestyle choices. There are 7 types of hair loss. These are androgenetic alopecia, alopecia areata, telogen effluvium, traction alopecia, trichotillomania, scarring alopecia, and drug-induced hair loss.
Note that three of them are considered the main types because of their underlying biological mechanism while the others are classified based on their non-biological underpinnings. It is also important to note that each type requires specific treatment option, For example, in the case of alopecia areata, minoxidil is ineffective and finasteride is not recommended.
Main Types of Hair Loss Based on Biological Mechanisms
1. Androgenetic Alopecia
The most common type of hair loss in terms of documented cases and prevalence is androgenetic alopecia. This is also called male-pattern hair loss or MPHL when it affects men and female-pattern hair loss or FPHL when it affects women. Furthermore, considering its biological mechanism, it is also classified as a form of non-scarring hair loss.
Sensitivity to androgens is the main culprit behind androgenetic alopecia. For example, in men affected by this condition, they tend to have high levels of dihydrotestosterone or DHT, which is a byproduct of testosterone. They also tend to have lower-than-normal values of sex hormone-binding globulin, follicle-stimulating hormone, testosterone, and epitestosterone.
The exact mechanism behind cases of androgenetic alopecia in women remains unknown. The consensus is that androgens are still important contributing factors. Estrogen dysregulation affects the hair follicle growth cycle. High levels of DHT in women also cause their hair follicles to shrink and result in an above-average rate of hair fall.
• Risk Factor: The cause of androgenetic alopecia stems from a combination of different factors including genetics, aging, metabolic syndrome, and smoking. Men are more susceptible to this condition. Women remain at risk.
• Presentation: Androgenetic alopecia causes thinning of hair on the crown and temples in men and thinning on the top of the scalp in women. Loss of hair becomes noticeable in older men and women beginning around the age of 30 and 40 although androgenetic alopecia has occurred in younger adults and even teenagers.
• Treatment: Treatment options include androgen-dependent medications such as finasteride or other DHT blockers and antiandrogen medications, and androgen-independent medications such as topical minoxidil, collagen induction therapy or derma-rolling, and topical melatonin, among others.
2. Alopecia Areata
Hair loss can also result from the immune system attacking the hair follicles. This condition is called alopecia areata or spot baldness. It is considered an autoimmune disease and it specifically results from a breach in the immune privilege of hair follicles. The general mechanism centers on the failure of the body to recognize its own cells.
Moreover, in describing the specific mechanism, this type of hair loss involves the immune system recognizing hair follicles either as foreign or abnormal. It then recruits immune cells such as T cells to attack the site. Active immune cells release signaling molecules and immunomodulating agents called cytokines.
Some cytokines have pro-inflammation effects. Their presence inflames the hair follicles and forces them to enter a dormant or telogen phase prematurely. This disrupts the hair growth cycle. Continuous attacks from the immune system result in chronic inflammation which then causes more hair to fall and can potentially lead to complete baldness or alopecia totalis.
• Risk Factor: The main risk factors are genetics, female gender, and the presence of other autoimmune diseases such as rheumatoid arthritis or celiac disease, and metabolic conditions such as type 1 diabetes. Chronic stress has also been regarded as a factor in triggering autoimmune conditions.
• Presentation: Remember that alopecia areata is also called spot baldness. The actual presentation is characterized by the presence of small and round patches of hair-less spots on the scalp or other parts of the body. Severe autoimmune cases or unmanaged conditions can lead to complete baldness.
• Treatment: The hair may regrow in most cases. However, in severe cases or if the condition results in psychological distress, available treatment options autoimmune treatments such as triamcinolone injections, hair loss treatments such as the application of minoxidil or platelet-rich plasma injection, or lifestyle change.
3. Telogen Effluvium
Another type of hair loss based on a biological cause is called telogen effluvium. This is a scalp disorder that occurs when a large number of hair follicles enter the telogen phase and leads to the thinning or excessive shedding of hair.
Hair fall is normal. An otherwise healthy individual can shed around 100 strands of hair per day. However, in those with telogen effluvium, they shed up to 300 strands of hair per day. Diagnosis includes trichogram, trichoscopy, and biopsy.
Studies have pinpointed five possible disruptions in the normal hair growth cycle. These are immediate anagen release, delayed anagen release, short anagen syndrome, immediate telogen release, and delayed telogen release.
• Risk Factor: The known risk factors and specific causes of hair loss due to telogen effluvium include pregnancy and childbirth, poor diet and eating habits leading to poor nutrition intake, severe emotional disorders, hypothyroidism, chronic stress, chronic illness, major surgery, and certain medications.
• Presentation: Hair loss due to hair follicles entering the telogen phase prematurely does not show patterns, unlike androgenetic alopecia, or does not occur in specific spots, unlike alopecia areata. Shedding occurs across the scalp but thinning is noticeable on top of the head. Strands of hair are visible when washing or combing.
• Treatment: The treatment option for telogen effluvium includes the use of topical medications such as minoxidil, stemoxydine, Nioxin, or a formulation that combines other topical ingredients such as melatonin, caffeine, niacinamide, panthenol, dimethicone, and an acrylate polymer.
Other Types of Hair Loss Based on Non-Biological Causes
There are other types of hair loss with no direct biological underpinnings or causes. Some of them are behavioral or are a result of certain choices. They can be resolved by addressing the underlying causes. Hair regrowth commences once these causes are addressed. Take note of the following types of hair loss based on non-biological causes:
4. Traction Alopecia: Prolonged and excessive tension on the hair can lead to a specific type of hair loss called traction alopecia. This specifically occurs from tight hairstyles like braids, weaves, and ponytails that cause the hair strands to break from the root and lead to permanent hair loss if unaddressed.
5. Trichotillomania: This is a mental or behavioral disorder that is also colloquially called hair-pulling disorder Afflicted individuals developed a compulsion to pull out their hair in response to specific triggers or during a heightened emotional state. Excessive pulling leads to patchy hair loss and bald spots.
6. Scarring Alopecia: Hair follicles can be destroyed and replaced with scar tissues due to injuries, burns, infections, or autoimmune disorders. The condition is called scarring alopecia. The scarred area would not be able to heal and the hair follicles would not be able to regenerate leading to permanent baldness.
7. Drug-Induced Hair Loss: Another type of hair loss is induced by certain medications. Drugs used in chemotherapy to fight cancer hasten the normal hair growth cycle which leads to excessive shedding. Other drugs such as blood thinners and antidepressants can also lead to excessive shedding of hair.
