What Does Testosterone Do for the Body, Exactly?

Suspect you’re suffering from low testosterone? You’re not alone, and knowledge is power. What does testosterone do for the body? Find out here.

What makes a man, a man?

Ask 100 people and you’ll get 100 different answers. Some will say how he treats others. Some will say strength and stamina. And still, others will cite perseverance or kindness and care for other.

But the question becomes easier, and the answers more consistent, when we focus that question on the biological. What makes a man a man? Traits that start to appear as a young teen – like face and body hair, more muscles and even getting taller. All traits that are brought on by the increase in production of a hormone called testosterone.

What Does Testosterone Do and What is it?

Testosterone is what we call a sex hormone, which means exactly what you think it does (and more). It’s got a lot to do with the things that make visibly define “maleness” as one of the sexes. And a lot to do with the act of sex, too.

Otherwise known as the male hormone, testosterone starts to increase in boys as they enter puberty. It causes the male sex organs – the penis and testes – to mature. Thanks to testosterone, young men start to grown body hair and their voices get deeper.

Any mother of a teen boy will tell you that they get taller, sometimes seemingly growing overnight. And both their bones and their muscle get stronger, thanks to testosterone.

And in addition to maturing the male sex organs, adequate levels of testosterone help men to make sperm. This makes testosterone an important male sex organ, no matter what definition you use.

The levels of this hormone increase throughout boyhood and peak during a man’s 20s. But after the age of about 30 to 35, testosterone levels start to drop, slowly.

The decline in the male hormone can be associated with a lot of things considered “normal aging” in men. Things like reduced libido and reduced muscle mass are tied to declining testosterone levels.

One thing that isn’t? Male pattern baldness. The connection between hair loss and testosterone is a complicated one but isn’t really affected by the decline in the hormone caused by age.

But just because testosterone drops off in all men over time, it doesn’t mean that the drop off is consistent or that, sometimes, it isn’t a greater drop than it should be.

What are the Signs of Low Testosterone?

As you’d imagine, the signs of low testosterone mirror the signs of increased levels of the hormone. But, interestingly, the symptoms go beyond just those traits. The signs of low testosterone include:


With reduced levels of testosterone, many men complain of feeling tired all the time, barely having the energy for their day to day lives, let alone the activities that they enjoy. If you are feeling tired all the time and have low energy, despite having gotten enough sleep, you may be experiencing the effects of low testosterone.

Significantly reduced libido

While many men experience declining sex drive as they age, men suffering from significantly reduced levels of the male hormone have almost no drive at all. Testosterone is a key component in stimulating the sex drive, so it’s no surprise that when the hormone is low, so is the libido.

Erectile Dysfunction

Just like its influence on libido, testosterone plays and important role in achieving and maintaining an erection. While the hormone isn’t directly responsible for erections, it does stimulate the parts of the brain that trigger them.


As we saw above, testosterone is what helps young men gain muscle mass as the move through puberty. A lack of the hormone can have the opposite effect. What’s worse, if levels are low enough, even going to the gym and weight training may have limited results.


Because testosterone influences so many functions of the body, men can feel symptoms, including mood swings, similar to those experienced by women going through menopause.

Difficulty concentrating and making decisions

This goes hand in hand with the above point. A man’s ability to focus on tasks at hand can be challenged with significantly low levels of the hormone. Along with that, they can experience what feels like an inability to concentrate or to make decisions as they did in their youth.

One of the biggest challenges facing men who are experiencing these symptoms is getting to the bottom of the issue. Many of these symptoms can also be present with a number of other health issues, such as diabetes, high blood pressure, and coronary disease.

What Can You Do?

If you’re experiencing any of the above symptoms, it’s important to get to the bottom of what is causing them. First and foremost, you should make an appointment with your doctor. A simple blood test can help determine if the issue is low testosterone, or if there is another problem that is causing the symptoms you’re experiencing.

There could also be an underlying condition, like medication side effects, infection, diabetes or liver disease that is causing the low levels of testosterone. If that’s the case, you’ll want to address the cause of the problem as well as the low hormone levels.

There are a number of treatments that you can discuss with your doctor, such as hormone injections, and gels. What’s important is that you look beyond simply correcting the problem that brought you in, and get help for all of the associated problems as well.

Discussing treatment with a physician who understands that the problem goes beyond just the treatment of hormone levels will get you back to where you deserve to be quicker than just putting a “band-aid” on the problem.

If you’ve dealt with issues like weight gain or muscle loss, erectile dysfunction, low sex drive, depression and so forth, you’ll need to work with a professional that can get you back on the path to well-being.

But keep in mind that low testosterone can all go beyond the obvious symptoms that brought you in. Increased cholesterol, decreased bone mass and depression should all be effects of low testosterone that should be addressed during treatment as well.

Make sure you’re seeing a doctor who recognizes your low hormone levels as part of the bigger picture and will get you back on the path to complete health.