It is a common belief that virile men with high testosterone levels experience hair loss earlier in life than other men. This image is reflected in popular culture, where muscular alpha males, usually known for their sporting or ‘hard man’ prowess, often have bald heads. But what are the facts behind this assumption?

It is true that hair loss and testosterone levels are linked. However, there is no scientifically proven link between levels of testosterone present in the body and a propensity to early baldness. Even men with low levels of the primary male sex hormone sometimes go bald early in life.

The role of genetics

Scientists believe that a certain combination of genes are the real clue as to whether a person will lose their hair or not. Genetics are hereditary, meaning that a person is born with them already present in the body. Part of this genetic makeup is an enzyme that can convert testosterone into a substance called dihydrotestosterone, or DHT.

The role of DHT

DHT causes the hair follicles to shrink in some people, which may be because the blood supply and nutrients are choked off. As the follicle shrinks, the resulting hair growth is finer and shorter, until only a layer of very fine baby hair, or ‘vellous hairs’ are left. Eventually, the follicles stop maintaining growth altogether, and the scalp becomes bald.

The resulting hair loss typically follows the path of male pattern baldness, starting at the hairline and crown, and then moving to the rest of the head. It is thought that men who go bald in this manner are more sensitive to DHT. It doesn’t affect the follicles on the chin, which is why you often see a bald man with a beard or goatee.

Hair loss in men is very common, with an estimated 40% showing signs of baldness by the age of 35. About 25% of men experience hair loss before the age of 21, and by the age of 50, it is thought that 85% suffer ‘significant thinning.’ For some men, this is not a problem, but others dislike the loss of a youthful appearance and even feel a sense of shame.

Can male pattern baldness be treated?

Early attempts to cure baldness focused on direct applications of testosterone to the scalp, but of course, this made no difference at all. Once scientists discovered the presence of the enzyme that converts testosterone into DHT, they sought to find ways of blocking the enzyme.

This approach has resulted in a treatment called finasteride, which is one of the most popular ways to tackle hair loss. It is a prescription medication that is taken orally. It contains a 5-AR inhibitor which directly blocks the enzymes responsible for converting testosterone into DHT.

Finasteride has been proven to be effective in 66% of patients, after a 12-week course of treatment. It can be bought online after a consultation with a pharmacist. It is designed specifically to interact with the male sex hormone testosterone, so it is not suitable for women who are suffering from hair loss.