Hair has a very close relationship with hormones. Male hormones inhibit hair growth, while female hormones promote hair growth instead. In particular, male hormones act in a completely different way in all parts of the body, or in the occipital and frontal parts of the head. The perception of testosterone related to hair in a person’s head varies from one part to another. The key to these phenomena lies in the hormone receptive discs, or receptive bodies. The hair papilla cells in alopecia are responsible for hair growth, and studies of the receptive bodies have shown that the hair cells on the top of the head in men have more binding proteins that are part of the male hormone receptive plate than the hair on the top of the head in women. The number of receivers in the hair papilla cells is determined by genetics. Initially there are individual differences in individuals or the fact that hair loss is inherited in a family system. Not only that, but whether or not the hair will go bald, or whether there will be differences in the number of testosterone receivers in the same person’s head depending on the location, is influenced by the number of testosterone receivers in the hair papillae. Testosterone promotes hair loss because it is related to the hair mother cells. Testosterone, which is produced by the testes, reaches the hair bulb cells in the bloodstream and enters the cytoplasm through the cell membrane. The cytoplasm contains the enzyme 5α-reductase, which changes the action of testosterone to the hormone 5 times more potent DHT (dihydrotestosterone). The powerful DHT enters the cell nucleus and has an effect on the metabolic system. In particular, the production of ATP substances, which have a cellular energy effect, is hindered. When ATP, which is a source of heat, is not produced, protein synthesis of the hair is not possible, and the hair mother cell loses its vitality and begins to keratinize, finally becoming a resting hair. The hair that enters the resting phase will lose its hair within about 3 months. In conclusion, DHT is the real culprit of male pattern baldness, which can have a toxic effect on hair follicles, causing them to gradually atrophy, leading to a shortened hair growth cycle and thus triggering the process of male pattern baldness. The cause of male pattern baldness has only been discovered in recent years, as the testosterone secreted in certain body tissues (like the hair follicles of the scalp) can be formed through the action of 5a-reductase (5α-reductase). Androgenic baldness occurs in specific areas where the hair follicles have different resistance to male hormones, mostly on the forehead, top of the head and the top of the back of the head. These hair follicles are genetically different and have poor resistance to DHT, as the genes begin to manifest after puberty. In these areas, the hair follicles are prone to produce large amounts of 5a-reductase, and the DHT produced by post-pubertal males is highly destructive to these hair follicles. These hair follicles have a large amount of 5α-reductase, which converts the male hormone into a large amount of metabolite dihydrotestosterone (DHT), and the hair follicles begin to shrink and degenerate, and the older you get, the more DHT accumulates and the more pronounced your baldness becomes.