Men tend to lose hair with increasing age. However, the pattern of losing hair varies from person to person. While in some men the loss is hardly noticeable, in others, it becomes quite noticeable due to the severity of loss of hair or its occurrence at a younger age.
It is important to note that the hair loss in men occurs in a few particular areas of the scalp. This relative loss at each of the areas determines the pattern of hair loss progression of other areas of the scalp.
- Balding in the temple area begins at the frontal part of the hairline and keeps moving backward. All men experience this to some extent during their transition from an adolescent to an adult. Only less than 5% men have been found to retain a straight frontal hairline as seen among the young boys. Normally the hair loss is mild in this area. But, some men have been found to develop a receding hairline that often precedes hair loss in some other areas of the scalp with passing years.
- Balding on the crown begins around the region of the whorl (back of our head) and then starts spreading outwards in all the directions resulting in a circular type of baldness. Another type of balding starts at a smaller region of the scalp, known as “6 o'clock border”.
- The diffused type of thinning occurs at the mid-frontal part of the scalp which widens the central part-line. Generally, Asian men suffer from this type of balding.
It is fascinating to know that the balding spreads from one hair follicle to the other without skipping any area. This eventually results in bitemporal recession producing an expanding triangle (of balding) over each area of the temple without leaving a single follicle of the affected region. The same thing happens over the region of the vertex as well.
From this observation, one might conclude that some kind of balding chemical is moving from follicle to follicle, but interestingly, there is no such chemical identified in human bodies. It happens mainly because of hair miniaturization that is programmed into the DNA of hair follicle.
There is another pattern of losing hair, which is invisible; it produces thinning of hair that precedes the process of balding. This is commonly known as androgenetic alopecia. It first causes shrinking of the secondary hair so that only 1 terminal hair is produced by the follicular units instead of a tuft of hair. When the last fiber forming the tuft vanishes, the bald spot becomes visible.
Even after the 50 % reduction in hair volume, no bald spot can be noticed in human beings. Being less observant and having shorter hair, most men might not notice their hair loss until an explicit bald spot develops. The factor controlling the progression of hair loss has been found to be genetic and epigenetic.
While there are certain regions of the scalp that experiences baldness, there are also some zones which do not suffer from hair loss, such as occipital scalp (or back of our head). This has made baldness optional for men. Through hair transplantation surgery, hair from the back portion of the head can be borrowed to fill the gaps on the frontal part of the head.