Signs and symptoms of low testosterone levels in men

Reviewed by Karan Rana

Testosterone is a hormone found in men and women. In men, testosterone is mainly made by the testicles and testosterone levels are an important factor in sexual development and sexual function. In women testosterone plays an important part in sexual function and overall good health. 

This article discusses what low testosterone in men is in more detail and explores the causes behind it. We look at the symptoms of low testosterone and treatment options available to you. And we also touch on low testosterone in women. 

What is low testosterone in men?

Low testosterone is a condition where the testicles do not produce enough testosterone. The testicles are the sex organs of those assigned male at birth. Testosterone is the major androgenic steroid sex hormone in males and has a number of important roles including the development of secondary sex characteristics and maintaining the function of the prostate and seminal vesicles.

Generally testosterone levels over 12 nmol/L and under 30 nmol/L are thought to be normal, anything under would be retested as it would be deemed to be low or borderline. If after retesting your testosterone is under 8 nmol/L, it’s likely you have testosterone deficiency (low testosterone levels).

It’s worth noting that testosterone is also a naturally occurring hormone found in women and plays an important part in sexual function and overall good health. 

What causes low testosterone in men?

Testosterone levels begin to fall naturally in men around the age of 30-40. The decline is steady, at a rate of about 1% a year and this is unlikely to cause any problems. There are other causes of low testosterone, however, that may induce symptoms. These can be classified as primary testosterone deficiency and secondary primary deficiency. 

Primary testosterone deficiency

This type of low testosterone is caused by a failure of the testicles to make enough testosterone. This might be due to:

• Testicular injury
• Chemotherapy or radiotherapy
• Undescended testicles
• Mumps
• Haemochromatosis (an inherited condition that causes the body to absorb too much iron)
• Klinefelter’s syndrome (a genetic condition men, who usually have one X and one Y chromosome, have more than two X chromosomes as well as a Y)

Secondary testosterone deficiency

With this type of low testosterone the testicles are normal but don’t produce enough testosterone because of a problem with another part of the body, e.g., the pituitary gland or hypothalamus. This might be down to:

• Problems with the pituitary gland
• HIV/AIDS
• Some opiates or hormones treatments

How do you know if you have low testosterone levels for a man?

The only way to know for sure if you have low testosterone levels is to have your levels checked with a blood test. You can do a blood test yourself at home, our men’s health blood test looks at 4 testosterone biomarkers to check your levels. 

Testing is available through the NHS if you are experiencing associated symptoms. As well as a total testosterone level blood test, you may also be asked to have a luteinizing hormone (LH) blood test and prolactin blood test as these can help establish the cause of low testosterone. 

Symptoms of low testosterone in men

Low testosterone doesn’t always result in physical symptoms. However, there are a range of symptoms associated with low testosterone levels including:

• Reduced sex drive
• Erectile dysfunction
• Hair loss
• Loss of muscle mass
• Fatigue
• Weight gain/loss
• Depression

These symptoms can be the result of other conditions as well, so if you are experiencing any of the above and are concerned, you should contact your GP to get the necessary investigations done to find the root cause.

How do you treat low testosterone in men?

A low testosterone level and its symptoms can be treated through testosterone replacement therapy (TRT). TRT is different to testosterone boosters which is the term used to describe over-the-counter supplements, natural remedies and illegally-obtained medicines used to self-treat symptoms such as erectile dysfunction. TRT is available in several forms including:

• Skin patches
• Gels
• Oral therapy
• Testosterone injections

Can women have low testosterone levels?

Premenopausal women naturally produce testosterone, and it plays an important role in general health and sexual function. It is produced in different locations in a woman’s body including the ovaries, adrenal gland, and peripheral tissues. The naturally occurring level of testosterone in women is less than in men, with the NHS citing the normal range between 0.7 and 2.8 nmol/L, but this can vary. 

As with men, a woman’s testosterone levels naturally decrease, particularly during menopause. Women who have had their ovaries surgically removed or whose ovaries have been damaged by chemotherapy can also experience low testosterone levels.

Low testosterone levels in women can cause symptoms including diminished sexual desire, difficulty in reaching orgasm and reduced vaginal lubrication.

How do you treat low testosterone in women?

If a woman is experiencing a low sex drive as a result of low testosterone levels, this can be treated with testosterone. In menopausal women, this testosterone is often given as part of standard hormone replacement therapy (HRT) as a gel or in sachets. It can take several months to work and for symptoms to be alleviated but it isn’t an effective treatment for every woman.

Summary

In summary, testosterone is an important hormone that is produced by both men and women. Testosterone naturally decreases with age but there are other causes, such as obesity, testicular injury and issues with the glands in the brain that can lead to low testosterone levels.

In men, low testosterone levels can lead to a range of symptoms including erectile dysfunction, reduced sex drive and weight loss or gain. In women, it can cause a loss of libido, especially once women reach menopause.

Low testosterone can be treated with testosterone replacement therapy (TRT) which is available in a variety of forms including injections, gels and patches. TRT should not be confused with testosterone boosters, which are supplements purported to increase testosterone and improve symptoms such as low libido and erectile dysfunction.

If you are experiencing symptoms of low testosterone you should speak to your doctor or another medical professional. They will be able to talk through your history, conduct a blood test to check your testosterone levels and try to establish the cause.

If you'd like more information on low testosterone in men, you can visit this BSSM resource. 

References

https://www.urologyhealth.org/urology-a-z/l/low-testosterone
https://www.gloshospitals.nhs.uk/media/documents/Testosterone_replacement_for_women_GHPI1700_10_21.pdf
https://www.nhs.uk/conditions/male-menopause/
https://bssm.org.uk/wp-content/uploads/2023/02/BSSM-Practical-Guide-High-Res-single-pp-view-final.pdf
https://patient.info/mens-health/erectile-dysfunction-impotence/testosterone-deficiency
https://www.southtees.nhs.uk/services/pathology/tests/testosterone/
https://www.guysandstthomas.nhs.uk/health-information/testosterone-low-sex-drive-menopause