What is Testosterone?

Medically approved by
Dr Earim Chaudry
Last updated
18th October 2021

In 30 seconds…

What is testosterone? Testosterone is an androgen or male hormone that helps us develop and regulate our typically ‘male’ characteristics – such as our body hair, muscle mass, bone density, and sperm count. It’s produced in specialised cells in our testes and our adrenal gland.

The hormone is also responsible for our mood and sexual health. Men with low testosterone often report low mood, fatigue, reduced libido, and difficulty achieving an erection.

These symptoms can be more common than you think, as testosterone levels drop by about 1% each year after 30. If you feel that your testosterone is too high or too low, there are ways that you can take control. Testosterone support supplements can help.

Testosterone: The Man Hormone

Most of us know the hormone thanks to its overblown association with “masculinity.” But testosterone isn’t all bulging biceps and raging libidos (although there’s nothing wrong with that). Instead, testosterone is a misunderstood and frankly underestimated hormone that does more and less than you may think.

Here, we make things a little clearer. So, what is testosterone? Let’s find out.

What is Testosterone?

Testosterone is an androgen, a male sex hormone. Hormones are substances that carry chemical messages around your body. Androgens are specific types of hormones that are responsible for developing and regulating your male sexual characteristics.

Testosterone is busy from a pretty early age, working to develop the male genitals from about 7 weeks after conception. At that point, the testicles – along with the adrenal gland – become the place where most testosterone is produced. This whole process is regulated by the brain and the pituitary gland, which acts like the “master” gland that controls many of your hormones.

Importantly, while convention calls testosterone the “male hormone,” this is quite misleading. Women also have testosterone. And while they need less of it, it helps their health too. In women, the hormone is produced in the ovaries and adrenal gland.

What Does Testosterone Do?

In men, testosterone does some pretty crucial work. Here’s some of what testosterone is responsible for:

  • Development during puberty. The deepening of the voice, facial and body hair growth, and widened shoulders all happen because of surging levels of testosterone.
  • Muscle, bone health, and body fat regulation. In both adult men and women, testosterone regulates your body shape and bone mass. The hormone enables you to burn fat properly when you exercise and keeps the balance of muscle and fat.
  • Sexual health. Testosterone maintains your sex drive, your sperm production, and your ability to achieve and sustain erections. Testosterone deficiencies have been linked to infertility (we’ll come back to that a little later on).
  • Mood. It’s likely that testosterone can help you to stave off depression and maintain a stable mood. But no, it’s highly unlikely that testosterone makes you aggressive.

Find out more: Testosterone and Aggression: The Relationship

And Hair Loss?

There are a lot of myths about testosterone in popular culture. One of them is that having higher than average testosterone levels makes you more likely to experience male pattern baldness. This isn’t strictly true.

Find out more: The Bald Facts: Hair Loss Myths & Tips

Male pattern baldness is actually caused by a hormone called dihydrotestosterone (DHT). It’s made from testosterone, but it isn’t testosterone. While it’s responsible for many important processes in your body, too, DHT causes your hair follicles to shrink, weaken, and stop producing hair.

That’s male pattern hair loss in a nutshell. There are plenty of ways to reverse it.

What Are Normal Testosterone Levels?

Many men worry that they don’t have normal testosterone levels or that their testosterone levels are decreasing. This is a legitimate concern – and it can be tough if you feel your “masculinity” is in decline. But it’s crucial that we’re clear about what’s going on here.

Firstly, it’s vital to know that testosterone levels are changing all the time. From the moment you wake up to the moment you go to bed, total testosterone levels are in flux. That’s completely normal.

More generally, though, testosterone levels reach their peak in your late teens and stay high for the next decade or so. After that, testosterone production decreases, usually by about 1% every year. By the age of 70, your testosterone production will be about 30% less than it was at its peak. However, the vast majority of older men will still have testosterone levels that are in the normal range.

Find out more about all of this in our article, Normal Testosterone Levels by Age.

Low Testosterone Levels: The Symptoms

In some men, testosterone levels can be lower than average. For many, this can be completely normal. For others, however, it can cause a condition known as low testosterone or low-T. Research suggests about 2% of older men may have a diagnosable testosterone disorder.

If you’re worried about your testosterone levels, look out for the following symptoms:

  • Erectile dysfunction
  • Reduced sex drive and sexual function
  • Loss of muscle and increased body fat, including breast enlargement
  • Loss of body hair
  • Mood changes, including fatigue, depression, and anger

Most commonly, low testosterone (or hypogonadism, as it’s sometimes known) is caused by damage to the testicles, problems with the pituitary gland, chronic diseases such as diabetes, prostate cancer, and alcoholism. Sometimes, it just happens.

The trouble is that these symptoms can simply be symptoms of ageing. A testosterone blood test can help you assess whether you have low testosterone levels.

How to Increase Testosterone Levels

The good news is that you can do things to help keep your testosterone at normal levels. Many are simple and require only minor changes to your lifestyle:

  • Firstly, take a testosterone test. Testing your hormone levels can show you whether you have low levels of testosterone or whether something else is affecting your health. You can take an easy testosterone blood test at home. Get one here. It can give you peace of mind.

    Important note: remember to test in the morning on fasting, between 7am-11am for the most accurate test results.
  • Improve your sleep. Sleep is the time when testosterone production happens. Trying to find ways to sleep better and for longer can be one of the most fundamental forms of testosterone treatment out there.
  • Exercise. It’s a way to help you sleep, firstly. But studies have found that the more active men are, the more testosterone they produce. Weightlifting is one of your best options.
  • Try vitamin D. Studies have found that a simple dose of vitamin D every day can boost testosterone levels by 25%.
  • Testosterone support. Natural extracts such as maca, ginseng, and zinc have been found to boost testosterone. Consuming enough of these natural remedies can help keep testosterone levels high. Try them here.
Testosterone Support

Keep those T levels up

The powerful threesome of Maca, Ginseng & Zinc is there to help you boost testosterone levels and, in turn, virility. Low T can be a libido killer.


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Key Takeaways

What is testosterone? It’s an incredibly active male hormone that’s produced in your testes. Testosterone affects your body mass, sexual health, mood, and many other areas of men’s health. Ensuring you maintain healthy levels – even into your later years – is essential.

Find out about your testosterone levels with Manual’s simple at-home blood test. 

While we've ensured that everything you read on the Health Centre is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. It should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your doctor.

Further reading

From our health centre. Experts, information and hot topics. See all Testosterone articles

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