What Is Testosterone?

What Is Testosterone?

What is testosterone? CJA Balance, UK-wide help, men low testosteroneTestosterone is a hugely important hormone that is needed for so many aspects of a man’s health.

It plays a key role in the development of male reproductive tissues such as the testes and the prostate, as well as stimulating the development of male characteristics such as increased bone mass, muscle mass and the growth of body hair.

Present in much greater levels in men than women, testosterone helps to regulate sex drive, or libido. It is important for sexual and reproductive development, fertility and also aids cognitive function, mental health and energy levels.

The level of testosterone peaks in adolescence and early adulthood and slowly decrease after the age of 30.  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, with health problems including frailty, depression and erectile dysfunction.

Having low testosterone can make you feel grumpy, low in mood and anxious and may lead to more serious health issues. When combined with a decrease in sex drive and the reduced ability to maintain an erection,  it is clear to see how low testosterone levels can have a negative affect on 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 at-home blood test to test your testosterone levels.  Find out more about the testosterone blood test here.

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How Do Our Bodies Regulate Testosterone?

The hypothalamus and the pituitary gland are both found in the brain. They are important in controlling the amount of testosterone produced by the testes.  When there is a high level of testosterone in the bloodstream, the hypothalamus lowers the number of gonadotrophin-releasing hormones that are released. When there are low testosterone levels, the number of gonadotrophins released is increased.

What Are The Signs of Low Testosterone?

There are many signs of low testosterone that alone could be mistaken for stress, depression or other issues. One of the biggest challenges facing men who are experiencing these symptoms is getting to the bottom of this.

Many of these symptoms can also be present with several other health issues, such as diabetes, high blood pressure, and coronary disease. If the symptoms are present together they can create a clearer picture of low testosterone. If you are concerned that you may have low testosterone levels, we advise you get a blood test from CJA Balance to check your levels.  You can also take our low testosterone quiz which gives a good indication as to whether you have low testosterone.

The signs of low testosterone include, but are not limited to:

  • Significantly Reduced Libido

Whilst many men may experience a decline in their sex drive as they age, men suffering from significantly reduced levels of the male hormone have almost no sex drive at all.

Testosterone is a key component in stimulating the sex drive, so it makes sense that when testosterone levels are low, the libido is affected.

  • Erectile Dysfunction including Loss of Morning Erections

As explained above, testosterone plays an important role in libido, and is a significant part of men achieving and maintaining an erection. Whilst the testosterone hormone isn’t directly responsible for erections, it does stimulate the parts of the brain that trigger them. Find out more about erectile dysfunction and treatments.

  • Fatigue

With reduced levels of testosterone, many men complain of feeling constantly tired, with barely the energy for their day to day lives, let alone any other activities such as exercise. If you find that you seem to be tired all of the time, it may be a sign of low levels of testosterone.

  • Weakness

Testosterone is the hormone that helps young men gain muscle mass as they move through puberty, and a lack of testosterone can have the opposite effect. If testosterone levels are very low, weight training to increase muscle mass will have little effect.

  • Depression

Because testosterone influences so many functions of the body, men with low levels of testosterone can experience symptoms including low mood and depression more frequently than men with normal levels of testosterone.

  • Difficulty Concentrating & Making Decisions

The ability for men to focus on tasks at hand can be challenged with significantly low levels of testosterone. They can have trouble decision making and concentrating on one task at once, similarly to during puberty when testosterone levels can fluctuate.

What Are The Average Levels of Testosterone in Men?

Testosterone levels in men are dropping year by year and the reasons for this are unknown.  It may be due to more unhealthy lifestyles, obesity or environmental factors, and research continues to find the cause. 

We also know that testosterone levels gradually drop in men from the age of 30 onward.

Knowing the average testosterone level for your age can be extremely useful. Once low levels of testosterone are identified, your odds of a successful treatment are increased.  If low testosterone symptoms aren’t managed, they can lead to a frustrating experience for you.

 In otherwise healthy, non-obese men aged 20-40, normal testosterone levels range between 8 to 29 nmol/l. Men at the lower end of this range often suffer from significant symptoms. If in doubt, please take our low testosterone quiz here Please note:  nmol/l = nanomoles per litre. 

What Are The Causes of Low Testosterone?

There are three types of hypogonadism (low testosterone): 

  • Primary Hypogonadism

Underactive testes cause primary hypogonadism, because they don’t manufacture sufficient testosterone levels for optimal growth and health. This underactivity can be caused by accident, illness or can be hereditary.

Hereditary conditions include:

Undescended testicles: This means that the testicles failed to descend from the abdomen before birth/

Klinefelter’s syndrome: This is a condition in which a man is born with three sex chromosomes as opposed to two: X, X, and Y.

Hemochromatosis: This is where there is too much iron present in the blood, which can cause testicular failure or pituitary damage.

The types of testicular damage that can lead to primary hypogonadism include:

Physical injury to the testicles: The injury must occur to both testicles at the same time to affect testosterone levels.

Cancer treatment: Chemotherapy or radiation can damage testicles and reduce testosterone levels.

Mumps: Mumps can injure testicles, reduce fertility and lower testosterone levels.  

  • Secondary Hypogonadism

Secondary hypogonadism is caused by damage to the pituitary gland or hypothalamus. These parts of the brain regulate testosterone levels in the body.  Conditions in this category include:

Inflammatory diseases: Diseases such as tuberculosis, sarcoidosis, and histiocytosis can impact the pituitary gland and the hypothalamus, reducing testosterone levels.

Pituitary disorders: Disorders which can be caused by drug abuse, prescribed medications, kidney failure, or small tumours.

Kallmann syndrome: This condition has been connected to abnormal hypothalamus function.

HIV/AIDS: HIV & AIDS can affect the hypothalamus, pituitary gland and testes as well as other functions in the body.

Circumstances that can lead to secondary hypogonadism include:

Natural Ageing: Ageing naturally affects the production and regulation of hormones, including testosterone.

Obesity: High body fat percentages can affect hormone production and regulations.

Medications: Opioid pain medications and steroids can affect function of the pituitary gland and hypothalamus.

Concurrent illness: Severe emotional stress or physical stress from an illness or surgery can cause the reproductive system to temporarily shut down, reducing production of testosterone.

  • Mixed Hypogonadism

You may be affected by primary, secondary or mixed hypogonadism. Mixed hypogonadism is more common with increased age. It also can affect men undergoing glucocorticoid therapy, those with sickle-cell disease, thalassemia, or suffering from alcoholism.

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