Dihydrotestosterone ( sometimes called DHT) is an important sex steroid that is produced by both men and women. DHT is utilized in greater quantities by men. DHT is created when an enzyme named 5aR metabolizes with an androgen (male sex hormone), usually testosterone.
Dihydrotestosterone helps regulate everything from neurological health to blood cell production. However, as crucial as this steroid is for the body to properly function, it can also cause certain physiological changes. Alopecia (balding) can be one of these changes. This can happen in both genders but is particularly prevalent in males.
There are many DHT receptors located throughout the body, especially in the hair follicles. Some people’s hair follicles are extremely sensitive to DHT due to their genetic predispostion. For this population, if enough Dihydrotestosterone accumulates over time, it can block an important structure within the follicle called the dermal papilla. The dermal papilla is what delivers nutrients to the hair bulb (a hair bulb is where the beginning of a new hair begins, kind of like a seed) and allows the hair shaft to grow. Therefore, if this structure becomes blocked, important vitamins, proteins and other nutrients cannot reach the hair bulb in order to stimulate growth and the anagen (growth) phase no longer occurs.
For the people with this genetic predisposition, DHT actually causes the hair follicle itself to shrink, and new hair follicles cannot grow downward into the scalp. Simply put, Dihydrotestosterone can sometimes clog the scalp’s tissue to the point where hair is no longer able to grow.
It is not uncommon for a person to spend most of their younger years unaffected by Dihydrotestosterone, only to develop a sudden sensitivity that causes them to bald with age. This is because Dihydrotestosterone can trigger a dormant gene to become expressive. This basically means that a genetic switch is flipped that causes the dermal papillae to become susceptible to Dihydrotestosterone. This can happen at any time in life, but typically occurs in the later years.
Certain medications can stimulate hair growth by halting the 5aR enzyme from metabolizing testosterone into Dihydrotestosterone. This blocks its detrimental effects to hair follicles. These medicines are called 5 Alpha-Reductase Inhibitors and they prevent large concentrations of Dihydrotestosterone from forming in scalp tissue. Less Dihydrotestosterone in the tissue means that the dermal papillae will be able to deliver nutrients to the hair bulbs and resume healthy growth.
Men and women utilize Dihydrotestosterone in the natural chemistry of their body. Men also rely on it for prostate growth and heavy muscle growth. In fact, the secondary characteristics of male puberty (voice deepening, facial hair, and body hair) are all caused by Dihydrotestosterone as well.
Dihydrotestosterone is what triggers the prostate to develop. It also never stops stimulating the prostate to grow. Cells in the prostate constantly multiply, and the likelihood of a mutation greatly increases with age. Sometimes these mutations take the form of Benign Prostate Hyperplasia, which is considered to be a potential precursor to prostate cancer.