TRT in the UK

How is Testosterone Produced in Men?

How is Testosterone Produced in Men?

By Mike Kocsis | 3 minutes read | Last updated: January 27, 2023 |
  • Categories:
  • Medically Reviewed by Dr. George Touliatos

    Evidence Based Research

    Testosterone is a vital hormone that is responsible for the development of male physical characteristics. In men, testosterone is primarily produced in the testes, but several parts of the body have to work together to ensure that testosterone is produced correctly and the body remains healthy.

    In this guide, we’re going to look at how the hormone is produced in men, starting with the brain, and then moving on to the testes as well the other parts of the body. Stay tuned!

    Take Hormone Quiz


    The hypothalamus is the part of the brain responsible for homeostasis, or the internal balance of the body. This includes the production of hormones for the endocrine system, as well as linking the endocrine system to the nervous system. It is the hypothalamus that initially triggers the release or inhibition of hormones. In the case of testosterone, it is the hypothalamus that tells the pituitary gland it must release hormones to stimulate testosterone production. To do this, the hypothalamus releases gonadotrophin-releasing hormone.



    The two different hormones released by the pituitary gland serve different purposes in reaching the testes. FSH is responsible for sperm production, whilst LH specifically stimulates the production of testosterone. It does this by influencing a special type of cell called a Leydig cell. When Leydig cells are activated, they begin to convert cholesterol into testosterone.

    Most cholesterol reaches the bloodstream through diet, particularly in foods such as bacon and eggs. Cholesterol is produced by the testes if there is not enough in the bloodstream, but this is less effective and can inhibit the Leydig cells. It is cholesterol absorbed from the bloodstream that is most important for testosterone production.

    There is a small amount of testosterone produced by the adrenal glands, only about 5%. The other 95% in men comes from the testes. In women, the majority of their (lower level of) testosterone comes from the ovaries, though again some is produced in the adrenal glands.


    Pituitary gland

    Many of the hormones that control the endocrine system have their origins in the pituitary gland (a pea-sized gland found at the base of the brain). As well as the testes, the adrenal glands and thyroid gland are at least partially controlled by the pituitary gland. The hypothalamus gives the instruction, but then the pituitary gland actually releases or inhibits the hormones.

    When the hypothalamus tells the pituitary gland that the testes need to produce more testosterone, the pituitary gland begins releasing other hormones, known as gonadotrophic substances. These include follicle-stimulating hormone (FSH) and luteinising hormone (LH). LH, in particular, will compel the testes to produce more testosterone. If the level rises by too much, the hypothalamus will tell the pituitary gland to stop producing LH.



    Newly produced testosterone is sent from the testes to the bloodstream and carried to where it is needed. Some will become inert when it attaches to various proteins, whilst a small amount will freely travel to areas of the body where masculine characteristics develop. If the hypothalamus decides that testosterone in the blood has achieved an appropriate level, it will reduce its production of gonadotrophin-releasing hormone, which in turn will cause the pituitary gland to reduce its production of LH. This production and reduction form an ongoing cycle.

    Order Blood Test

    Incorrect levels

    Sometimes, the body will not produce the correct amount of testosterone. An excess can cause early puberty in younger children, sometimes leading to infertility. Conditions that cause excess testosterone production include congenital adrenal hyperplasia, androgen resistance and ovarian cancer. The use of anabolic steroids can also interfere with testosterone levels.

    Book Free Consultation

    Low-T can delay puberty, as well as have a negative effect on muscle mass, bone density, body fat, libido and mood. Otherwise known as hypogonadism. Some reduction in testosterone production is normal as a man ages. However, if the low -t  symptoms persist, you may need to be treated with testosterone replacement therapy (TRT) If you feel you may be suffering from low-t levels, dont hesitate to get in touch with our specialised doctors by hitting the contact us button above!

    Was this article helpful?

    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.

    We value your feedback on our articles, if you have a well-researched paper you would like to share with us please contact us.

    Quick Low Testosterone Test

    If you know your total testosterone reading from a previous blood test input the results to the left above to see if your testosterone levels are normal.

    Check your testosterone

    Tick all that apply:

    I have the following symptoms:

    Testosterone conversion tool
    Order testosterone blood tests

    Low Testosterone Levels

    You may have low testosterone depending on the symptoms you have, please contact us to find out how we can help.

    Take our ADAMS low testosterone questionnaire.

    Please Retry

    The Total Testosterone Level You Entered Is Incorrect. Figure Must be in nmol/L you can use our converter here.

    Take our ADAMS low testosterone questionnaire.

    Normal Testosterone Levels

    Your testosterone levels appear to be in the normal range.

    Take our ADAMS low testosterone questionnaire.


    You must be over 38, have had your ovaries removed or have suffered with premature menopause to warrant further hormone tests.

    Take our ADAMS low testosterone questionnaire.

    Further investigation needed

    Please contact us to discuss your hormones, we need your total testosterone levels to validate your hormone deficiency. You can order a blood test here.

    Take our ADAMS low testosterone questionnaire.

    Low Testosterone Levels

    You may have low testosterone depending on the symptoms you have, please contact us to find out how we can help.

    Take our ADAMS low testosterone questionnaire.

    High Testosterone Levels

    You appear to have higher than normal testosterone levels, please contact us for further investigation.

    Take our ADAMS low testosterone questionnaire.

    Normal Testosterone Levels

    You appear to have normal testosterone levels. Contact us if you have any concerns.

    Take our ADAMS low testosterone questionnaire.

    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.

    Learn More About Us

    Last update: January 27th, 2023
    Male Pattern Hair Loss and Hormones
    Male Pattern Hair Loss and Hormones
    24 November, 2023, by Mike Kocsis

    Men lose 50 to 100 hairs every day. Your hair falls out, and new hairs take their place as their growth cycle begins.  However, sometimes you start losing more hair than you grow. As a result, thin hair patches appear on your head. Data show more than 85% of men lose hair at some time […]

    Read Article
    Primary Hypogonadism: Symptoms, Causes, and Treatments
    Primary Hypogonadism: Symptoms, Causes, and Treatments
    13 November, 2023, by Mike Kocsis

    Male hypogonadism is a condition in which your body fails to produce sufficient male sex hormone, testosterone, which plays many crucial roles in the body. It can affect men of any age; however, it is more prevalent in middle to old aged men. Data shows that 35% of men older than 45 years have primary […]

    Read Article
    The Relationship between Low Testosterone and the Immune System
    The Relationship between Low Testosterone and the Immune System
    27 October, 2023, by Mike Kocsis

    Testosterone, also referred to as the ‘king of hormones’ for men, plays a crucial role in driving libido, regulating mood, and maintaining bone density. But did you know testosterone’s influence extends far beyond these well-known roles? Recent studies have unveiled an interesting relationship between testosterone levels and the immune system. Keep reading the article to […]

    Read Article

    Get In Touch

    File(s) size limit is 20MB.

    Book a FREE consultation
    With Balance My Hormones.

    Get Started Today
    Evidence based
    research backed
    hormone optimization

    Balance My Hormones helps customers restore their hormones to optimal levels through bespoke TRT and HRT treatment plans. We use modern American treatment methods and have over 25 years of experience in hormonal health which is backed up by our very own GPhC pharmacy.