この記事の概要
There are marked differences in the rate of hair growth cycles (phases) in different parts of the head. Especially in the case of male pattern baldness (AGA) and female pattern baldness (FAGA), there are differences in the rate of hair growth and the progression of hair loss in different areas of the head. Each area of the head has a different growth cycle due to hormonal influences and differences in blood flow. Below is a detailed description of the different hair growth cycles for each area and how they affect hair loss.
- top of head
The proportion of hair in the anagen phase tends to be small: In male pattern baldness, the hair on the top of the head is especially sensitive to DHT (dihydrotestosterone), so the proportion of hair in the anagen phase decreases, and more hair tends to transition to the resting phase. There is. As a result, hair on the crown of the head thins faster than in other areas.
Progression of hair loss: The proportion of hair in the telogen and catagen phases increases in this area, making hair loss more likely. - anterior head
High rate of catagen/telogen: Hair on the front of the head is also susceptible to DHT, which shortens the growth phase and increases the number of hairs that enter the telogen phase. This often results in thinning of the hair on the front of the head.
M-shaped receding: Especially in men, the hair growth cycle on the front of the head is disrupted, causing the forehead hairline to recede into an M-shape. - temporal and occipital regions
High proportion of hair in the anagen phase: Hair on the sides and back of the head is said to be less susceptible to the effects of DHT. Therefore, these areas have a high proportion of hair in the growth phase and tend to be less prone to hair loss.
Stable growth: The hair on the sides and back of the head is relatively likely to remain even if androgenetic alopecia progresses, and hair from these areas is often used as a donor for hair transplant surgery. - Balance of the entire crown of the head
Female pattern baldness: Women tend to experience thinning evenly across the top of their heads, and are less likely to noticeably affect just one area. However, the proportion of hair in the anagen phase decreases overall, and the proportion of hair in the telogen and catagen phases increases.
Summary
The proportion of phases in the hair growth cycle can vary by site on the head, with a tendency for fewer hairs in the growing phase and more in the resting and regressing phases, especially in areas that are strongly affected by hormones. This causes hair loss to progress in certain areas. If you would like to have a test to see if minoxidil is effective for you, we recommend that you take hair from the back of your head, where the percentage of growth phase is higher, to perform the test so that we can get as accurate a test result as possible. If you would like to know if minoxidil is effective for you, please contact HIRO CLINIC.
