The most common type of male hair loss is androgenetic alopecia. This type of hair loss affecting 98% of men, characterized by hair receding from the lateral sides of the forehead (known as a “receding hairline”) and/or a thinning crown (balding to the area known as the ‘vertex’). Both hair recession and hair thinning become more pronounced until they eventually meet, leaving a horseshoe-shaped ring of hair around the back of the head. Apart from androgenetic alopecia, there is also telogen effluvium and non pattern hair loss. The former is hair loss that is usually caused by the likes of medication, diet patterns, stress, and thyroid abnormalities. The latter relates to any random and rare hair loss experienced, such as scarring alopecia and compulsive hair pulling (also known as trichotillomania).
Androgens act by interacting with specific receptors. They are found on cell membranes or inside cells, as all other hormones do.
- Two types of androgens causing male pattern hair loss. The trigger is enzyme 5-alpha reductase which turns inactive testosterone into dihydrotestosterone (DHT hormone). Once DHT is formed it has the ability to overpower any androgen molecule present on a hair follicle. Plain testosterone can also act on the follicles, but its effect of causing hair loss is weaker.
- The combination of testosterone and dihydrotestoterone, break down the hair growth cycle by making the anagen (growth) phase progressively shorter.
- The catagen (intermediate) and telogen (shedding or resting) phases remain the same resulting in an increased number of resting hair follicles within the hair growth process. The more hairs that enter the resting phase increase the number of shedding hairs.
- The shedding (telogen) process starts with a decrease in length and fullness. Hairs grow thinner and shorter leading to brittle hairs that are prone to fall out.
Telogen effluvium, is hair loss due to an increased number of hair follicles entering the resting stage. The most common causes of Telogen Effluvium are :
- Blood pressure medications, gout medications or high doses of vitamin A
- Hair loss may also occur due to Franchised diet programs which are designed or administered under the direction of a physician with prescribed meals, dietary supplements, where many of them are high in vitamin A which can magnify the hair loss.
- Emotional stress, surgeries and severe illnesses can cause hair loss. The body simply shuts down production of hair during periods of stress since it is not necessary for survival and instead devotes its energies toward repairing vital body structures. In many cases there is a three month delay between the actual event and the onset of hair loss. Furthermore, there may be another three month delay prior to the return of noticeable hair re-growth. This then means that the total hair loss and re-growth cycle can last 6 months or possibly longer when induced by physical or emotional stress.
NON-PATTERN HAIR LOSS
In men more rarely than in women, hair loss may be due to conditions other than androgenetic alopecia. Some of the most common of these causes are:
- Alopecia Areata. This is autoimmune disorder also known as “spot baldness” that can result in hair loss ranging from just one location (Alopecia areata monolocularis) to every hair on the entire body (Alopecia areata universalis). Although thought to be caused by hair follicles becoming dormant, what triggers alopecia areata is not exactly known. In most cases the condition corrects itself, but it can also spread to the entire scalp (alopecia totalis) or to the entire body (alopecia universalis).
- Triangular Alopecia. Loss of hair in the temporal areas that sometimes begins in childhood. Hair loss may be complete, or a few fine, thin-diameter hairs may remain. The cause of triangular alopecia is not known, but the condition can be treated medically or surgically.
- Trichotilomania is the loss of hair caused by compulsive pulling and bending of the hairs. Due to the constant extraction of the hair roots, permanent hair loss can occur. Onset of this disorder tends to begin around the onset of puberty and usually continues through adulthood.