Most people will lose some hair, and that alone is not the type of male hair loss that some men are worried about getting as they get older.
Because of this and the fact that male pattern baldness is so common even if it is also often very treatable, a lot of misconceptions, legends and stories have emerged about why hair loss happens.
One of the most common of these found in bodybuilding and fitness circles is the belief that the more testosterone you have, the more likely you are to go bald, with the implication then that baldness is a sign of high testosterone and by extension virility.
It is not quite that simple and clear cut, as whilst there is certainly a connection between testosterone and both hair growth and hair loss, the connection is more complex than many conversations in gyms and locker rooms would claim.
How Does Testosterone Cause Hair Loss?
It is important to note that in the human body, there are multiple types of testosterone and it is important to know what testosterone actually does in the body.
Testosterone, often known as the “male hormone” despite being present in men and women, contributes to characteristics such as muscle mass, sexual health, bone density and body hair growth, and a lot of it is bound to proteins and sex hormone-binding globulin (SHBG) in the body.
What is left is known as “free testosterone” which can take a number of forms and act in a number of ways around the body, one of which is to be converted via an enzyme into dihydrotestosterone (DHT.
DHT is five times as potent as regular testosterone and it is this form of testosterone that binds to hair follicles in the scalp, which makes them shrink, which can cause weaker, thinner hair that eventually stops growing entirely.
DHT is also linked to slower healing, heart disease and prostate issues if there is too much in the body, whilst too little can cause issues with body fat distribution.
This is part of the reason why the treatment finasteride is sometimes used to help treat male pattern baldness as well as benign prostate enlargement (BPE). It reduces the level of DHT in the body.
Does High Testosterone Always Cause Hair Loss?
Where the claims that testosterone causes baldness are wrong is the idea that this is always the case because ultimately the bigger determinate factor for hair loss is genetics.
People have different levels of sensitivity in their hair follicles, and some people are much more heavily affected by DHT than others. This is determined almost entirely by the AR gene and so different people can have varying levels of testosterone and still be at a healthy level.
As well as this, the production rate of the enzyme that creates DHT can vary in different people, meaning that some people with male pattern baldness do not necessarily have high testosterone levels but more of their free testosterone is being converted to DHT.