Hair loss (alopecia) can be due to various factors, sometimes permanent and sometimes transient. Stress, poor eating habits, medication or certain conditions such as anemia, thyroid or skin conditions can lead to hair loss.
1. Androgenic alopecia
The most common type of male pattern baldness is androgenetic alopecia, which accounts for 95% of baldness cases. It can also appear in women with some variations and in a smaller – although not negligible – percentage. Unlike other types of hair loss, androgenetic alopecia is not associated with inflammation or scarring.
Unlike other types of hair loss, androgenetic alopecia is not associated with inflammation or scarring.
Both the onset and progression of the condition are gradual and manifest cyclically with periods of ups and downs, while it consists of both a reduction in the density and quantity of hair.
Initially, thinning occurs in the forehead area, progressing to the front, top, and top of the scalp. The occipital (back) and parietal (side) regions are mostly unaffected
2. Normal hair growth cycle
An adult has approximately 100,000 to 150,000 hairs which are renewed at a different rate based on the hair growth cycle which includes three phases:
Ι. Phase of Development or Regeneration (Anagen Phase)
ΙΙ. Catagen Phase
IΙΙ. Telogen Phase
During the first phase which lasts 2 to 6 years the follicles are located deep in the skin producing thick, brightly colored hairs that grow at a constant rate every day. Normally at any given time the largest percentage of hair – about 85%, is in the above phase.
The second phase is an intermediate stage in which the hair prepares for apoptosis by shrinking the hair follicles. About 1 to 2% of the hair is in this stage which lasts 2 weeks.
The last phase lasts about 3 to 4 months. Hair stops growing until it eventually falls out.
Based on the cycle above, a daily loss of 100 to 150 hairs is considered normal. In the event that this is greater and for a prolonged period of time, we can talk about hair loss.
3. Causes of Androgenic Alopecia
Androgenetic alopecia is caused by a genetically determined increased sensitivity of the hair root to the hormone dihydrotestosterone (DHT) that worsens with aging. We can therefore talk about three main causes associated with this particular type of hair loss, which are considered in combination and not individually.
4. Genetic Predisposition – Heredity
Genetic predisposition is a strong factor in the occurrence of androgenic alopecia, but it is not absolute that every person who has this predisposition will eventually develop the condition. Although the exact way in which it is inherited is not known, it is certain that the gene responsible for the occurrence of this type of hair loss is inherited from the mother’s side. In practice, this means that although the predisposition can be inherited from both parents, this is certain only if there is a history on the mother’s side. In any case, however, what is certain is that even if a person with a genetic predisposition eventually develops hair loss, the time of occurrence and the rate of progression can vary greatly.
5. Biological ripening
Naturally, with the process of biological maturation, hairs weaken, and hair growth decreases. Its effect on the creation of hair loss consists of the time during which sensitive hair follicles are exposed to the degenerative action of androgens. Androgenic alopecia is, therefore, not a normal result of the aging process, which, however, acts catalytically when the two factors coexist.
La tipologia più comune di calvizie maschile è l’alopecia androgena, che riguarda il 95% dei casi di calvizie. Può manifestarsi anche nelle donne con alcune varianti e in una percentuale minore, anche se non trascurabile. A differenza di quanto accade con gli altri tipi di caduta dei capelli, l’alopecia androgena non è associata a infiammazioni o cicatrici.
A differenza di quanto accade con gli altri tipi di caduta dei capelli, l’alopecia androgena non è associata a infiammazioni o cicatrici.
Sia l'insorgenza che la progressione della patologia sono graduali e si manifestano ciclicamente con periodi di alti e bassi, con la sussistenza di una riduzione della densità e della quantità dei capelli.
Inizialmente il diradamento avviene nella zona della fronte, progredendo verso la parte anteriore, superiore e posteriore del cuoio capelluto. Le regioni occipitale (posteriore) e parietale (laterale) rimangono per lo più inalterat
Naturalmente, con il processo di maturazione biologica, i capelli si indeboliscono e la loro crescita diminuisce.
Il suo effetto sulla genesi della caduta dei capelli è dato dal tempo durante il quale i follicoli piliferi sensibili sono esposti all'azione degenerativa degli androgeni.
L’alopecia androgena non è quindi un normale risultato del processo di invecchiamento, che però agisce come un catalizzatore quando i due fattori coesistono.
