What causes hair loss in men? Research into male hair loss causes has revealed that up to 40% of men have noticeable hair loss by the age of 35, 65% of men experience hair loss by the time they reach 60, and 80% of men will suffer from a form of hair loss at the age of 80. The correlation between age and hair loss is evident and there is no doubt, just from observing people in everyday life that with age, a person's total hair volume will decrease. There are however, 2 other factors, or hair loss causes, that are known to increase the rate at which male pattern baldness, the most common type of hair loss in men occurs: genetics and hormones.
The existence of the necessary genes and hormones alone is not capable of signalling the onset of hair loss. Even after a man reaches sexual maturity, the weaker of hair follicles must continually be exposed to a certain hormone over a period of time for baldness to occur. There is no set age for which these effects fully kick in, more so it is dictated by a man's genetic composition and to the levels of testosterone in the bloodstream.
Usually hair loss cannot occur without the presence of specific inherited genes, from either the male or female bloodline. Hair loss in men is now believed to involve more than one gene, meaning that a hereditary baldness trait can be inherited from the mother's side of the family just as easily as the father's side.
Just because a person carries the baldness gene, it doesn't mean the trait will fully develop. The likelihood of that gene manifesting itself as hair loss is dependent on a person's age and their hormonal balance. External hair loss causes such as high level of stress can also intensify the chances of hair loss occurring.
Testosterone and other male sex hormones are made primarily in the testicles; therefore, a fully grown man will not have significant hormonal levels until the testicles develop and enlarge during puberty. These same hormones that cause acne and beard growth can also initiate the onset of baldness. When androgens; testosterone, and its related hormone DHT are present, some follicles wither and die.
The hormone known to be directly responsible for the development of male pattern baldness is called dihydrotestosterone (DHT). It is created by the action of the enzyme 5-a reductase on testosterone and affects the continuity of the 3 stages of the hair growth cycle.
DHT shortens the length of the growing cycle, and increases the resting phase, so that with each new cycle the length of a single hair shrinks time and time again until it is too short to grow through the hair follicle. DHT also causes prostate enlargement in older men and adolescent and adult acne.
The enzyme 5-a reductase, which leads to the production of DHT can be stopped by the hair loss medication finasteride. Propecia, the brand name for finasteride is an oral treatment used for the most common of hair loss causes, male pattern baldness.