What are the causes of hair loss?
Hair loss can be caused by several reasons: genetic traits, diseases, stress, injury, medicines, and aging. The most common cause of hair loss, or alopecia, is genetic; this means that it is inherited. Alopecia can be inherited from both sides of the family and can affect women and men. The way in which it affects the members of the same family is random: it could skip a generation, or it could affect a sibling and not the other. Moreover, hair loss within the same family could be caused by different reasons.
Androgenetic is a type of hair loss due to a susceptibility of the hair follicle to an androgenetic miniaturization. It is the most common type of stuttering and affects 70% of males and 40% of women at some point in their lives.
Male Pattern Baldness
Androgenetic hair loss in men begins over the temples and at the vertex of the scalp. As it progresses, a strip of hair on the sides and behind the head is kept. This condition is called ‘Hippocratic Crown’ and rarely advances to a complete baldness.
Female Pattern Baldness
Androgenic alopecia in women is also called ‘female baldness’, although its features may also occur in men. It is usually a widespread thinning without a recession of the hairline, and as the male counterpart rarely leads to a complete baldness (alopecia totalis).
Other Causes of Hair Loss
Traction Alopecia is a type of alopecia that occurs in the form of an alteration characterized by the presence of irregular areas with thin, partially broken and largely missing hair. It is quite common, especially in female subjects, as it is more common for them to use extensions, clips, elastics, etc. The cause is therefore not an excessive and localized baldness, but rather an alteration in the process of hair regrowth. The damage does not manifest itself immediately, but it is the result of slow and profound anatomical changes in the follicle which takes in time dystrophic features.
Many empty infundibular channels can be seen and many follicles are seriously damaged. Therefore, fine, weak, twisted hairs are originated. The surrounding tissue is then replaced by fibrous – scar tissue. This results in the impossibility of generating hair again. Traction alopecia should therefore be recognized as early as possible to intervene before an irreversible damage occurs.
Trichotillomania is an obsessive-compulsive disorder characterized by an irrepressible impulse to pull and tear hair from the scalp. The pathological event may be directed to eradicate eyebrows, eyelashes, beards, and other body hair, including those covering the abdomen, legs, arms, armpits or pubic areas.
Sometimes, this condition is self-limiting, but it is always advisable to resort to a doctor who can advise on the most appropriate therapy.
Alopecia areata is a pathology in which the sudden fall of hair, or other body hair, typically manifests itself in glabrous patches or areas from which it takes its name. Usually, the first spots appear in the scalp and in most cases, it is resolved spontaneously without showing any signs of scarring. In about 1% of cases, the disease may extend to the entire scalp (total alopecia, AT) or the whole body (universal alopecia, AU) with a total loss of all body hair.
Scarring alopecia is due to the destruction of the hair follicle and its replacement with scar tissue which results in permanent hair loss. In some cases of scarring alopecia, hair loss is progressive and asymptomatic and remains unnoticed. In other cases, scarring alopecia is accompanied by itching, burning, and pain and progresses rapidly. In the scarring alopecia, the inflammation that destroys the follicular sacs is under the skin and the scar is not visible. The skin affected by the scarring alopecia is usually reddened and shows flaking, hyperpigmentation or hypopigmentation. Scarring alopecia can occur in men and women of all ages, even if they are healthy in every respect.
Scarring alopecia can be distinguished in secondary, primary, and subcutaneous alopecia. In the primary, the cause is usually endogenous. An inflammation attacks the hair follicle and destroys it. In secondary alopecia, the cause is exogenous, i.e. a trauma, an inflammation, a wound, a burn, a traction, or a neoplasm.
Brittle and dry hair which weakens and falls easily is a common symptom of thyroid disease. Capillary follicles are particularly sensitive to the health of the body and tend to slow down their activity in the presence of significant psycho-physical stress. In this way, it is possible to allocate more energy resources to support vital functions. It is not surprising then that increased hair loss is common in the presence of nutritional deficiencies, infections, surgery, burns, hormonal changes and various diseases, including thyroid.
The patient may complain of a bad state of health of their hair both in the presence of hypothyroidism and hyperthyroidism. In addition to the possible increase in fall, which usually occurs in tufts, hair may become fragile, smooth and opaque.
Although in the vast majority of people hair loss is an almost physiological event, it is not wise to underestimate the hypothesis of an underlying thyroid disease, especially in the presence of familiarity with this kind of disorders.
The treatment of thyroid disorders very often stops hair loss, although it takes a few months to appreciate some aesthetic improvement. However, some medicines used to treat such diseases – such as Eutrox (Levothyroxine) – may contribute to hair loss, especially if taken in inappropriate dosages. For this reason, once the correct therapeutic dose is found and the problem persists, it is necessary to inform a physician and undergo a dermatological examination to exclude other predisposing conditions.