Hair miniaturization occurs when hair follicles shrink in size, causing hair shortening, where strands become thinner, weaker, and break more easily. This process is gradual and, if left untreated, eventually leads to hair loss.
Androgenic alopecia, commonly known as pattern baldness, is a common reason for hair loss in both men and women. Hair miniaturization is the hallmark of androgenic alopecia. (1)
In normal conditions, adults have terminal hairs on the scalp, which are long, thick, pigmented hairs. On the scalps of people with androgenic alopecia, these terminal hairs are progressively reduced, gradually turning into short, thin, wispy, lighter hairs known as vellus or “baby” hairs.
What Causes Hair Miniaturization?
Androgenic alopecia has a strong genetic component. Three main factors are involved in the process of hair miniaturization: hormones, inflammation, and the disruption of the normal hair growth cycle.
DHT Binds to Hair Follicles
You’ve probably heard of the hormone testosterone. Testosterone isn’t responsible for hair loss, but another hormone that it converts to, called dihydrotestosterone (DHT), is. Testosterone converts into DHT using a special enzyme called 5-ɑ-Reductase Type 2.
The scalps of men with pattern hair loss tend to have higher than normal levels of DHT, along with the increased conversion of testosterone to DHT. DHT binds to androgen receptors located at the hair follicle, triggering hair miniaturization, excess hair shedding, and hair loss. This androgen is thought to be the main hormonal component behind hair miniaturization in male individuals.
The role of DHT in women with androgenic alopecia is not so clear. Some women have higher levels of DHT, while others have normal levels. Therefore, other factors likely cause hair miniaturization in female individuals and play a role in the progression of androgenic alopecia. (2)
The Hair Growth Cycle Is Disrupted
Hair is lost and replaced cyclically. The normal hair growth cycle involves three phases. The first phase is the anagen, also known as the active or growing phase of the cycle, which can last up to 7 years. During this phase, cells divide at a rapid rate, and hair grows about 1 centimeter per month.
The next stage, called the catagen stage, is a transitional phase that lasts a few weeks. The third stage is the telogen phase, also known as the resting phase. It lasts about 3 months and culminates with the shedding of the hair shaft. During this phase, the hair follicle is inactive.
In androgenic alopecia, the anagen phase decreases with each cycle, while the telogen phase remains the same or even increases. The length of the hair shaft decreases with each cycle as hair miniaturization increases. At the same time, the anagen phase becomes shorter. Eventually, growing hair no longer reaches the surface of the skin, leaving an empty follicular pore. (1,17)
Inflammation Worsens Miniaturization
Inflammation, an issue often associated with androgenic alopecia, worsens hair miniaturization. Although the exact role of inflammation in miniaturization is still under research, scientists believe that certain immune cells are activated and infiltrate the lower part of the hair follicle. (3) Research shows that drugs targeting inflammation may help manage androgenic alopecia in men, further confirming the importance of reducing scalp and follicle inflammation. (4)
Do Follicles Shrink in Other Types of Hair Loss?
Hair follicles can shrink due to androgenic alopecia and multiple other causes of hair loss. One example is aging: a very common cause of hair miniaturization. (5) The natural process of aging affects every single cell of the body. Chronic inflammation, degeneration, accumulation of free radicals, and nutrient deficiencies are all associated with the aging process. These factors have a negative impact on the hair follicles, too.
Hair Miniaturization and Telogen Effluvium
Telogen effluvium is a type of hair loss caused by emotional or physical stress. Stressors can vary, but include hormonal changes related to pregnancy or menopause, new medications, or nutrient deficiencies. In telogen effluvium, hair enters the telogen phase too soon. (6) As a result, the affected areas of the scalp will have less hair, and the hair may display signs of miniaturization.
Nutritional deficiencies have a negative impact on the structure and growth of the hair. Hair follicles require all essential nutrients. However, particularly important ones include (7):
- Vitamin A
- Vitamin E
- Vitamin C
- Vitamin D
- B Vitamins (like biotin and niacin)
- Omega-3 fatty acids
Hair Miniaturization: How To Tell if It’s Occurring
You can potentially tell that hair miniaturization is occurring if you find your hair becoming thinner and shorter. Thin hair follicles do not support healthy hair growth. While miniaturized hair can still grow long, it will look brittle and be weaker.
Hair miniaturization symptoms and signs can differ between men and women. But both men and women may notice more hair falling off on their pillows, in the shower, or when brushing their hair. If you consult a dermatologist, their careful examination may show an increase in the number of vellus or “baby” hairs present across the scalp, confirming that miniaturization is occurring. (8)
Is Hair Follicle Miniaturization the Same in Men and Women?
In men with pattern hair loss, a receding hairline and thinning hair at the crown of the head are highly suggestive of hair miniaturization due to androgenic alopecia. As miniaturization and hair loss progresses, the receding hairline forms an “M” shape. Eventually, the thinning across the top of the head results in baldness. Interestingly, the lower back of the head is not affected by hair loss, as this part of the scalp is not affected by the DHT hormone. (9)
The “pattern” in which hair is lost during androgenic alopecia is different in men compared with women. In female pattern hair loss, hair becomes thinner and loses density across the top of the head. Most of the time, the hairline does not recede. Women may see extensive thinning, but most will not experience baldness. (8)
Can You Reverse Hair Miniaturization?
Three main treatments — minoxidil, finasteride, and low-level laser therapy — aim to stop the progression of pattern hair loss and hair miniaturization. But early diagnosis and use of one of these treatments are essential to reverse the process of miniaturization. If the hair follicles are dormant for too long, they can not be saved, and this condition will inevitably lead to balding.
There is also hope for treating shrinking hair follicles in other ways. Preclinical studies have found that follicles can self-renew using special stem cells located in the hair follicle. These regenerate hair follicles also go through the hair growth cycles. However, there are no studies in humans to confirm these findings yet. (10)
Minoxidil is a topical medication that results in significant improvements in hair growth and decreases hair loss. It comes as a liquid and a foam in concentrations of 2 percent and 5 percent.
Both liquid and foam minoxidil solutions have been approved by the U.S. Food and Drug Administration (FDA) to manage pattern hair loss symptoms, though the 5 percent solution seems to be more effective. Minoxidil is thought to increase the growth phase of the hair growth cycle and follicular size. So if you’re looking for a way to stop hair miniaturization, minoxidil can help. (8,11)
Low-dose oral minoxidil is not yet approved but is being explored in clinical trials. In one study, low dose minoxidil combined with spironolactone showed decreased hair shedding and improved hair density in women with androgenic alopecia. (8) A review of multiple studies found that low-dose minoxidil may be an effective, well-tolerated alternative for people who have difficulty using the topical product. (11)
Finasteride is an FDA-approved oral drug used to treat androgenic alopecia in men. It works by blocking the enzyme involved in the conversion of testosterone into DHT. Research studies found finasteride slows down hair loss, increases hair growth, and improves the appearance of the hair. About 30 percent hair improvement is seen after 6 months of use. (12)
The use of finasteride for women with androgenic alopecia is controversial as it can be harmful to women who are or may become pregnant. A handful of studies found that it increased hair density and decreased hair shedding in women. (13)
However, a new version of finasteride – topical finasteride – is currently being explored as a new hair loss treatment for men and women. Topical finasteride significantly decreases the rate of hair loss and increases the number of total and terminal hairs. (14)
Getting Laser Hair Therapy
Laser hair therapy treatments, also known as low-level light therapy or low-level laser therapy (LLLT), use visible and near-infrared light to promote hair growth. Laser hair therapy devices are FDA-cleared for the treatment of androgenic alopecia. LLLT can help improve terminal hair growth and reduce inflammation. (12)
Other Hair Loss Treatment Options
Hair transplants can’t cure androgenic alopecia, but they can be a good option for people who have extensive hair loss. This surgical procedure involves harvesting healthy hair follicles and transferring them to areas of the scalp affected by balding. However, the cost of this treatment can be very expensive. (12)
If you’re not interested in medications or surgeries, it may be worth exploring natural remedies that can help manage androgenic alopecia symptoms. Plant-based products that may be helpful in reducing hair miniaturization include (15):
- Saw palmetto, pumpkin seed extract, and other DHT blocking nutraceuticals that work in a similar way to finasteride
- Rosemary oil, which has been shown to improve blood circulation, like minoxidil
- Green tea extract, which has strong anti-inflammatory and antioxidant qualities
- Grape seed oil and extracts, which may improve the hair cycle growth
Why Do Follicles Shrink and Can Hair Thinning Be Reversed?
Tiny hair follicles and weak, brittle hair are signs of hair miniaturization, a common sign of androgenic alopecia and aging. Most people experiencing hair miniaturization are affected by some combination of the hormone DHT, changes in their hair’s growth cycle, and scalp inflammation.
Early treatment can help stop and reverse hair follicle miniaturization. Minoxidil, finasteride, and laser hair therapy are all FDA-recommended options that can help decrease hair loss and improve hair health.
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- Xie Y., Chen D., Jiang K., Song L., Qian N., DuY., Yang Y., Wang F, Chen T.(2022),Hair Shaft Miniaturization Causes Stem Cell Depletion Through Mechanosensory Signals Mediated By a Piezo1-calcium-TNF-α Axis.Cell Stem Cell 2022 Jan 6;29(1):70-85.e6
- Shashikant Malkud (2015), Telogen Effluvium: A Review. Journal Of Clinical And Diagnostic Research. 2015 Sep; 9(9): WE01–WE03
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- Feinstein R P., Androgenetic Alopecia. Medscape. Updated: Jan 11, 2022
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- Mirmirani P (2015), Age-related Hair Changes In Men: Mechanisms and management of alopecia and graying. Maturitas, Volume 80, Issue 1, January 2015, Pages 58-62
- Iamsumang W., Leerunyakul K. and Suchonwanit P.(2020)Finasteride and Its Potential for the Treatment of Female Pattern Hair Loss: Evidence to Date. Drug Design Development And Therapy. 2020; 14: 951–959.
- Lee S W., MD,Juhasz M. Mobasher P., Ekelem C. and Mesinkovska N A. (2019), A Systematic Review of Topical Finasteride in the Treatment of Androgenetic Alopecia in Men and Women. Journal Of Drugs In Dermatology. 2018 Apr 1; 17(4): 457–463.
- Yusuf Dhariwala M., Ravikumar P. (2019), An overview of herbal alternatives in androgenetic alopecia. Review. Journal of Cosmetic Dermatology 2019 Aug;18(4):966-975
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Last updated August 2022