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What Does Testosterone Do?

What Does Testosterone Do?

By Mike Kocsis | 10 minutes read | Last updated: February 16, 2021
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    Though almost everyone has heard of testosterone and knows that it is a hormone in our bodies, not many people realize the full extent of testosterone and everything that it is responsible for in our bodies. While testosterone may be a casual topic of conversation for some, others know that it is one of the single most important parts of our bodies. Testosterone plays a much more important role than many realize.

    If you want to have good general health, then you need to have good hormone health. In this complete guide to testosterone, we are going to show you exactly what testosterone does and why it is one of the most important parts of your body. We’ll cover what testosterone does, what processes it is involved in, and what you can do to promote health with your testosterone and hormone levels.

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    What is Testosterone?

    Before we can truly understand testosterone and the role that it plays in the body, you will need to know exactly what testosterone is. Testosterone is a hormone in the body. Hormones are important chemicals that serve as the communication system for the body. They tell the parts of the body when to work and when not to work to produce important materials that the body needs to function and be healthy.

    Despite popular belief, testosterone is present in both men and women. Though, it is far more present in men than in women. Though both men and women require testosterone to survive and have normal body function, testosterone is a dire necessity for men, as it is the primary hormone in their bodies. Men that are low on testosterone will often feel extreme side effects. A normal testosterone level for men would be considered to be 300 to 1,000 nanograms per deciliter (ng/dL), and for women it is typically between 15 and 70 ng/dL

    Men that are low in testosterone have options, however. In addition to being low on testosterone, it is also possible to have higher testosterone levels than normal. Any sort of imbalance in testosterone levels can result in drastic side effects that are uncomfortable at best and debilitating at worst.

    Testosterone is an absolutely vital building block in the body of both men and women, with specific importance in the body of men, for whom testosterone is the primary hormone in the body and impacts many parts of their personal development.

    What Areas of the Body Does Testosterone Impact?

    If you want to truly learn the importance of testosterone in the body, then you should learn more about all the areas and processes of the body that testosterone has an influence on. Testosterone has its fingerprints all over our bodies and not only in body development but also in crucial, life-sustaining processes that keep us alive on a daily basis. Here are some of the areas of the body that testosterone has influence within, making it one of the most important parts of your body.

    Puberty & Body Development

    One part of the body that testosterone certainly has an incredibly heavy influence is in puberty and body development. When men go through puberty and their body develops over time, testosterone is a very important part of that development. Without sufficient testosterone, men will not be able to go through this transition or may have an incomplete transition. Males usually begin puberty and calling upon their stores of testosterone in their teenage years.

    Muscle Size and Strength

    Many people are familiar with the fact that more testosterone leads to more muscle growth and strength. In fact, many sports organizations have banned taking testosterone boosters for this very reason. You may have not put two and two together when it comes to the muscular development that can be enjoyed with high levels of testosterone, but is a very real thing. Having an adequate level of testosterone in your body is absolutely essential to maintaining proper muscle size and strength. It is not uncommon for men with low testosterone to have problems building and producing muscle.

    Bone Growth and Strength

    Most people will associate testosterone with building muscles, but testosterone also has a very large role to play in bone health. Men with proper levels of testosterone will find that their bones are strong and properly developed. Those that have bones that are still developing could certainly develop issues in bone growth and strength. If you want to ensure good bone health, you should make sure that your testosterone levels are regular.

    Sex Drive & Libido

    Perhaps one of the most well-known effects of low testosterone is sex drive and libido decrease. Testosterone in your body is responsible for developing a healthy and functioning libido. A decrease in testosterone can directly lead to an inability to have a healthy sex life. As you can imagine, this is more than just a physical side effect. This could damage relationships and mental health, as well.

    Sperm Production

    Testosterone is the most important hormone in the body of a male. It is responsible for many functions, but perhaps its most important role is the one that it plays in the reproductive system. In many ways, testosterone influences sperm production and allows men to have a healthy and fertile sex life. When men have low testosterone, they can have trouble producing adequate semen for reproduction.

    What Happens if There’s Too Much Testosterone?

    When it comes to issues dealing with testosterone levels, many people believe that you simply can’t have too much testosterone. While many people are focused on conditions surrounding low testosterone, there is such a thing has having too much testosterone. You might be wondering: if there are so many negative side effects associated with low testosterone, how could you possibly ever have too much? Well, it’s important to remember that hormones are healthy when they are balanced. This means that you should not have too much, nor too little. Achieving a balance is paramount to human health.

    That being said, having too much testosterone is not a very common problem with men. Men that have trouble with hormone balance are often the victim of having too little testosterone. Still, it can happen and there are very real side effects to going through it. In addition, it’s important to know that testosterone levels are a matter of balance, not just always having a lot of it.

    Much of the information that has been gathered about the side effects of having too much testosterone has been learned by studying athletes that have taken testosterone in order to boost their performance.

    Here are some of the potential side effects of having too much testosterone in your body:

    • Lowered sperm count
    • Testicle shrinkage
    • Enlargement of the prostate
    • Increased acne
    • Increased risk of liver disease
    • More fluid retention and bloating
    • Weight gain due to increased appetite
    • Higher blood pressure
    • Higher Cholesterol
    • Severe insomnia
    • Increased headaches
    • More risk of blood clots
    • Stunted growth, especially in adolescents
    • Aggressive behavior

    While many men are on the lookout for low testosterone, it is recommended that they monitor and avoid their testosterone levels getting too high, as well. Good hormone health means having well-balanced testosterone levels that are neither too high nor too low.

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    What Happens if There’s Too Little Testosterone?

    One of the most relevant issues that men struggle with on a yearly basis is low testosterone. As we have touched on several times over, testosterone is incredibly important for men and having the right balance is very important in maintaining good overall general health. While it is possible to have too much testosterone and what is really important is having a good balance (not too much, not too little), the condition that many men live in fear of is having too little testosterone. The reason for this is that without the right amount of testosterone in the body, men simply don’t feel like themselves. There are a variety of physical conditions that can be felt as a result of not having enough testosterone and it can really affect mental health, as well.

    There are a very wide range of side effects that can be felt by men that are going through having too low of testosterone levels. Here are some of them.


    Hormone balance plays a huge role in regulating our mood. Men that are going through low testosterone levels will often experience mental health problems including depression as a result.


    When our body does not have the tools that it needs, including a balanced hormone level, it can result in increased fatigue and lack of focus. Many men experience this while in school or at work, finding it difficult to get through the day.

    Lowered Muscle and Bone Density

    As we touched on earlier, testosterone plays a huge role–and not just in sex drive. Testosterone can also control the development of lean muscles and strong bones. This means that when it is low, it can have a hugely negative impact on your physical fitness and strength.

    Lowered Sex Drive

    Testosterone is the hormone that is responsible for your sex drive. Men that are low on testosterone will frequently experience drastically lowered sex drive, which can also damage personal relationships.

    Weight Gain

    Testosterone is heavily tied to your physical fitness and ability to have a healthy body. Those that have low testosterone are much more prone to experience weight gain and increased body fat.

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    What Can Cause Testosterone Production to be Faulty?

    If you are experiencing low testosterone or imbalance testosterone levels and trying to avoid it, then you may be wondering what could potentially cause an imbalance in hormones. There are a variety of reasons that a person could be experiencing low testosterone. Here are some of the potential reasons that men could experience imbalanced hormones that could cause severe side effects.


    One of the most common factors that can easily affect testosterone production is if the individual is suffering from an illness or disease. This could include a variety of things such as heart disease, cancer, or if they are undergoing chemotherapy treatments, which are known for being very hard on the body. Any of these can easily bring down testosterone production.

    Injury to Reproductive Organs

    Another instance that can affect the ability of the body to produce testosterone is possible injuries to reproductive organs. This can include injuries to the penis, testes, or other areas surrounding these reproductive organs.


    Many people don’t realize that the amount of stress in your life can dramatically impact the testosterone that you are able to produce. Individuals that are consistently under a lot of stress and don’t have good stress management tactics can commonly experience lower testosterone levels.


    Bad health and bad hormone levels often go hand-in-hand. If you live an unhealthy lifestyle and eat an unhealthy diet, it is much more likely that you will have issues with your testosterone levels. One thing to try if you are experiencing low testosterone is to improve your diet and health.

    Steroid Abuse

    If you have a history of using anabolic steroids and have since come off them this can cause your testes to not produce enough natural testosterone and will require you to recover from anabolic steroids in a specific way and most likely on-going testosterone replacement therapy treatment.

    What is Testosterone Therapy?

    For men that are experiencing imbalance in their hormones, it is important to remember that there are solutions out there that can help them to overcome the side effects of hormones that are imbalanced. One of the best things that you can do if you are experiencing unnaturally low testosterone levels is to go through testosterone replacement therapy (TRT).

    Testosterone replacement therapy is a common treatment among men that are experiencing low testosterone levels despite living a healthy and active lifestyle. Having low testosterone can be a very frustrating and demoralizing event for a lot of men, but testosterone replacement therapy helps with that–a lot!

    Testosterone replacement therapy is a direct way to inject testosterone into the body and ensure that the body has the adequate level of testosterone that it needs to properly function. Testosterone replacement therapy is becoming an increasingly trusted way to treat low testosterone and can help prevent many of the side effects that would otherwise come with low testosterone.

    If you wish to use testosterone replacement therapy, the best way to do so is to get in touch with a specialist that can administer high-quality, reliable, and affordable TRT and provide you with the guidance that you need to successfully use this treatment.

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    References / Study Material / Further Reading–what-it-does-and-doesnt-do

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    Evidence Based Research

    This article has been researched and written based on scientific evidence and fact sheets that have then been crossed checked by our team of doctors and subject matter experts.

    References, sources and studies used alongside our own in-house research have been cited below, most of which contain external clickable links to reviewed scientific paper that contain date stamped evidence.

    Our team of healthcare experts and GMC registered doctors are licensed to UK GMC standards. We strive to provide you with the latest evidence based, researched articles that are unbiased, honest and provide you with accurate insights, statistics and helpful information on the discussed topic to ensure you gain a better understanding of the subject. You can read more about our Editorial Process by clicking here.

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    About the Author: Mike Kocsis

    Mike KocsisMike Kocsis has an MBA with a focus on healthcare administration and is an entrepreneur and medical case manager for Balance My Hormones Ltd which offers medical services in the UK and Europe. Mike has over 20 years of experience in the healthcare sector, much of that working with people who have hormone imbalances. Mike has appeared on podcasts and radio and is an expert speaker on the subject of hormone imbalance. He specialises in Testosterone Replacement Therapy (TRT) and Hormone Replacement Therapy (HRT) and has helped thousands of people suffering from hormone imbalances recover and regain control of their lives. You can follow him on LinkedIn and on the Balance My Hormones YouTube Channel.

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    Last update: February 16th, 2021
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