What is Testosterone?

What is testosterone?

The Basics

Everyone has heard of testosterone – the chemical that makes men manly, strong and dominating. It makes your voice deep and your muscles big – but is it that simple? Is there more to it than meets the eye? What is testosterone?

Testosterone has a certain stigma attached to it in today’s society. It is often blamed for all kinds of things; from violence and aggression, to cheating in sports. But is it all bad? Does it have any positive effects? And why do so many men want more of it?

Some men have lots of it and some clearly don’t…

How do I know if I have high levels and what can I do about it if I don’t?

So what is testosterone?

What is Testosterone?

The chemical structure

Testosterone (not spelt testerone) is a hormone.

This means that it is a certain molecule in the body that attaches to cells to produce a response.

It is like a signal to cells to perform actions in certain situations. Because it is a chemical it can tell lots of different cells to do things at the same time.

This is called a systemic effect. It allows the body to make big changes that last for longer than signals from nerves.

It is produced by the male body from as young as 7 weeks old. Its production then peaks in the teenage years as a child goes through puberty.

After the age of 30 most men’s testosterone levels slowly decrease each year.

If a man does not produce enough testosterone it can lead to a condition called hypogonadism. This can have many negative effects, physically and mentally.

Testosterone Chemical Structure

What is testosterone ‘s role?

Testosterone has 100s of effects on the body, many of which are still not fully understood.

Here we will talk about the most common ones and how they are important for your health and well-being.

Optimal Testosterone


Even in the womb testosterone is responsible for the development of male genitalia. After conception they continue to grow. This growth increases rapidly during puberty where the penis and testicles grow and sperm is produced in the testes.

Body hair also begins to grow and sexual desire increases. The male’s face begins to become more masculine in structure and the bones begin to develop with a widening of the shoulders and increased bone density. Skin becomes thicker and muscles begin to grow larger.

Some men will not fully develop in puberty and will need testosterone to allow further development.

Testosterone Development

Muscles and bones

What is testosterone ‘s effect on muscle and bones after puberty?

Testosterone increases protein synthesis and muscle growth. It is released after exercise and helps with recovery.

Testosterone also works to improve strength through effects on the nervous system, especially when combined with resistance training.

This is why athletes take anabolic steroids to improve their performance.

Testosterone also increases bone density; this is very important in older men with lower testosterone levels.

Lower bone density increases the risk of frailty and broken bones. It can lead to a reduction in height and fractures (broken bones) in the spine. This condition is called osteoporosis and is common in older men and women.

Testosterone Muscles

Think you might have low testosterone?


Mood and psychological effects

We know that low testosterone can cause anxiety and depression.

It may leave you feeling grumpy and down.

But what is testosterone’s role in improving mood and affecting general emotions?

A recent study shows that testosterone was more effective than anti-depressants at improving mood and reducing anxiety and depression.

It works on the hippocampus, an area of the brain important in the study of depression and anxiety, to improve men’s moods and emotional states.

Testosterone Brain

Other psychological effects

Testosterone has other roles in psychology.

It has been shown to increase risk taking and competitive behaviour. Many top traders and company directors have higher testosterone levels than their counter parts.

Testosterone has also been shown to improve spatial awareness – this can perhaps explain some of the stereotypes around women’s parking abilities!

Higher testosterone men are known for being more assertive and even aggressive.

High testosterone men tend to display more dominating behaviours than those with low testosterone. In successful men with a higher status this is rarely seen as aggression or violence; it normally produces assertive behaviours and actions. However, in high testosterone men with a lower status this may be displayed as aggression or violence – this is perhaps why lower status, high testosterone men make up large portions of the prison population.

Sexual function

What is testosterone ‘s role in sex?

Clearly an increase in testosterone around the time of puberty is one of the main drivers of sexual desire and the development of sexual function.

But beyond this period testosterone continues to have an essential role in the maintenance of sexual function.

Testosterone is required to produce and maintain an erection.

Sexual Failure Low Testosterone
Higher testosterone levels lead to increased sexual desire/libido and increased frequency of erections.

Even the size and hardness of erections can be improved with good testosterone levels in men who have dipping amounts.

General health

More and more research is pointing towards the health benefits of normal testosterone levels.

A new paper has indicated that improving the testosterone levels of diabetics reduces their overall risk of death in a 6 year period. In fact, the men with low testosterone were 2.3 times more likely to die over this timeframe!


High Testosterone Healthy Man
In the same study, men with low testosterone were then split into those on TRT and those without. The men on TRT has a substantially lower level of mortality over the study period.

Normal testosterone levels have been linked to improved insulin sensitivity which allows the body to use sugars more effectively. This reduces the risk of developing diabetes.

Testosterone has been shown to improve heart health, by allowing men to exercise and gain more useful heart muscle from cardiovascular exercise.

Although there has been some concern about TRT having a negative effect on blood lipids, this isn’t shown by and research. In fact the opposite is true.

High normal levels of testosterone have even been linked to improved results in cognitive tests – it improves spatial and verbal memory.


So, what is testosterone?

Testosterone is a hugely important hormone that is needed for so many aspects of a man’s health. It does so much more than help to build muscle, facial hair and deepen a man’s voice!

In fact, having low testosterone makes you feel more grumpy, low in mood and anxious.

Not to mention the negative effects that low testosterone has on heart health and the risk of diabetes. Considering these are two of the biggest killers of men in modern society, the epidemic of low testosterone becomes an even bigger threat.

When combined with a decrease in sex drive and the reduced ability to maintain an erection this can become a cause for major concern in a man’s life and happiness.

If you think you may have low testosterone, or recognise some of the symptoms here, then you can order a discreet test to your home for only £59.99 which will look at total and free testosterone levels.

What is Testosterone

Think you might have low testosterone?