First and foremost, it is important to remember that you lose hair every day, without even realising it. This is a natural phenomenon that corresponds to the telogen phase of the hair cycle, during which the dead hair is gradually pushed out by the growth of a new hair in the follicle. This phase lasts an average of 3 months. This means that, if you notice more hair loss than usual, you’ll need to look back 3 months to identify the cause (1).
Physiological stress. Intense stress can disrupt the hair growth cycle by causing hair follicles to enter the telogen phase prematurely. Instead of continuing to produce keratin, they cease their activity – leading to hair loss a few weeks later. Nutritional deficiencies, psychological trauma and endocrine disorders are among the typical triggers in this category (2).
Mechanical stress. If you regularly wear tight hairstyles that pull your hair back (buns, ponytails, etc.), this may well be the cause of your hair loss. By subjecting your follicles to intense and repeated pulling, you risk damaging them. This trauma particularly affects the temples and forehead, where hair tends to thin (3). When the damage is too severe, the resulting hair loss can sometimes be irreversible.
A genetic predisposition. You may have heard of androgenetic alopecia. And with good reason: a scientific paper by Philipps Grant et al. states that this is the most common cause of hair loss in adults (4). It affects both sexes and its prevalence increases with age. It can be compared to a form of baldness of a genetic and hormonal nature 2 (linked in particular to the sensitivity of hair follicles to dihydrotestosterone, or DHT). The associated hair loss is therefore caused by follicular miniaturisation and an alteration in the hair growth cycle.
