Aging encourages hair loss affecting approximately 50% males / 20% females, tending to follow a typical receding pattern. Genetic pattern hair loss aside from other hair diseases starts from the top advancing down the head.
One of the causes of losing hair is the male hormone dihydrotestosterone (DHT). Testosterone converted in the body as DHT by the enzyme 5 alpha reductase, causes the growth of follicles to cease in people prone to their genetic make-up. This targets the crown and mid scalp areas. Frontal hair loss has other causes currently under research.