About hair loss
There are a lot of reasons to experience hair loss.
In normal conditions, we can shed around 100 hairs per day. It can be more during your hair wash day, for instance.
In Spring and Autumn we shed more hairs (everywhere, including brows and lashes!). Some people call it seasonal hair loss. Terrestrial mammals change their fur with the change of the seasons, to adapt to the change of temperature. The hair follicles "rest" during summer (the telogen phase) and enter the shedding phase (exogen phase) in fall mainly, and occasionally spring.
Temporary, stress-induced hair loss (telogen effluvium). Common during pregnancy, after the famous COVID-19, in moments of high stress (exams, new job). It does not last forever.
Androgenetic alopecia. In gents, knows as male-pattern baldness; more than 50% of men over age 50 have some degree of hair loss. There is an alteration in the hair cycle development, follicular miniaturization and inflammation. One of the molecules that intervene in the process is dihydrotestosterone (DHT), that binds to the scalp hair follicle androgen receptors. Scalp subcutaneous blood flow is also lower in this type of alopecia.
Alopecia. An autoimmune disorder: the immune defences of the body attack the body's hair follicles, resulting in hair loss in patches (alopecia areata), all over the scalp (alopecia totalis) or over the entire body (alopecia universalis).
How to tackle hair loss?