7 signs you could have low testosterone

Low testosterone can affect men of any age, but do you know the main signs of low testosterone?

Low testosterone can affect men of any age, but the signs of low testosterone are more likely to affect you as you get older. 

The symptoms of ageing often intertwine with the symptoms of low testosterone, but researchers are still trying to work out the exact relationship between low testosterone and ageing. We do know, though, that spotting low testosterone and treating it in the right way can be beneficial. 

We look at the signs of low testosterone so that you can spot them and act if you need to. 

In this blog, we discuss: 

What is testosterone?

Testosterone is a sex hormone that is essential for many functions in the body, including: 

  • Sex drive 
  • Muscle mass 
  • Fertility  
  • Mood

In most men, levels of testosterone increase from puberty to adulthood, then gradually decline from the mid-30s or 40s onwards. Some people call this middle-aged drop or the ‘male menopause’ – although the NHS describes the male menopause term as being a little misleading! That’s because it suggests the symptoms are down to a sudden drop in testosterone in middle age, like what occurs in female menopause, which isn’t true. While testosterone levels do fall as men age, it’s a steady decline or less than 2% a year from around 30-40 years old. 

Hypogonadism is when your body stops producing enough testosterone. Even though most men have normal age-related hypogonadism or late-onset hypogonadism, some men can have issues that cause testosterone levels to drop earlier in life, which is called early primary or secondary hypogonadism. 

So, how do you know if you have low testosterone? The most important thing is learning to understand yourself as a whole – both physically and mentally. Low testosterone is a complex issue. For some people, low levels of testosterone won’t cause any symptoms at all, but for others, it can significantly affect their quality of life. Here are some of the signs that may indicate that you have low testosterone.  

Signs you have low testosterone

1. Low libido 

Your libido is another word for your sex drive. And testosterone helps to fuel it.  

If your libido has gone from normal to low or non-existent, low testosterone may be a contributing factor.  

Low libido doesn’t just mean that you’re less interested in sex, but it can also refer to your feelings during sex itself. 

2. Erectile dysfunction 

Erectile dysfunction can happen to anyone. Getting and maintaining an erection is a more complicated affair than you might think. It’s a culmination of vascular, neurological, anatomical, situational, and psychological factors.  

One other factor is your hormones. Any disruption in the link between your testes and your brain, like low testosterone, can cause erectile dysfunction. So, if you’re struggling to get or maintain an erection, low testosterone may be one of the reasons why. 

It is also common to get nocturnal erections during REM sleep, which we often know about when waking up with one. If your ‘morning glory’ stops happening altogether, it could be a sign that your testosterone is low. 

Have a read of our blog: all you need to know about erectile dysfunction.  

3. Lack of muscle gains 

Testosterone is one of the most potent anabolic hormones (hormones that stimulate growth and development). It works directly on muscles to build them up and stop them from being broken down.  

The receptors on these muscles decline as we age, which means muscles don’t grow as much over time. But if you don’t have enough testosterone to stimulate these receptors, your muscle mass will also decline.  

If you’ve noticed you’re getting weaker or your muscle mass is falling off over time, then it might be a good idea to check your testosterone. 

Of course, low testosterone isn’t the only cause for lack of muscle gains. Read our blog: four reasons you’re not building muscle.  

4. Low mood and memory 

Testosterone acts as a signaller in the brain. Although mental health is very complex and unique to every person, testosterone plays a small but integral role. 

Low testosterone can lower your mood, possibly contributing to depression, and it may negatively impact your memory.  

We tend to see this most often in men as they get older, so if you have a low mood and you have low testosterone, you might be able to improve your symptoms by increasing your testosterone levels. 

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5. Fatigue 

As well as affecting your mood, low testosterone is associated with fatigue and feeling exhausted. So, if you find yourself constantly tired and don’t know why then checking your testosterone is not an unreasonable move. 

If your energy levels are at an all-time low, read our blog: five reasons you could be tired all the time.  

6. Body fat and man boobs 

Testosterone enhances the breakdown of fat and reduces fat uptake into tissues. As your levels drop, your body finds it easier to lay down visceral fat (fat around the tummy), which is associated with cardiovascular disease.  

Yet, being overweight also causes low testosterone, which makes it harder to lose weight. Fat can accumulate around the breast tissue too, leading to man boobs (gynecomastia).  

If you’re gaining weight or you’ve developed man boobs, it’s time to check your testosterone. 

7. Hair growth or loss 

Curiously, testosterone and its by-products can lead to both hair growth and hair loss.  

Again, there are different factors at play here, but some men with healthy testosterone levels will lose hair on their head but can grow a full beard and other body hair. For these men, if beard or body hair growth becomes difficult over time, low testosterone may be to blame. 

In some young men, low testosterone levels may contribute to early baldness. In these cases, you will also probably note other symptoms of low testosterone.  

For more on this, read through our blog: 6 surprising causes of hair loss.

How to investigate low testosterone levels

If you are experiencing any of the symptoms of low testosterone, taking time to assess your physical and mental self can help. If you do go on to take a testosterone test, make sure to share these symptoms with your doctor so they can interpret your results alongside them.  

Understand your physical self: 

  • What’s your weight? 
  • How much alcohol do you drink? 
  • Do you smoke? 
  • What’s your diet like? 

Understand your mental health: 

  • Assess your mood (both by yourself and with your trusted friends and family) 
  • Try to gauge your stress levels 
  • Try to assess your sleep 
  • Focus on your memory and make a mental note if you find it difficult to remember certain words 

Understand yourself on the inside: 

The best way to investigate low testosterone levels is to take a blood test. All testosterone blood test samples should be taken early in the morning. With a Medichecks test, your results will come with advice and any necessary follow-up steps from one of our doctors. 

Our Testosterone Blood Test is a simple blood test that you can do at home to measure the total level of testosterone in your blood. For a more comprehensive test, have a look at our Advanced Well Man and Advanced Well Woman Blood tests, which both include tests for testosterone. 

Remember, testosterone isn’t just important for men – women need it too.  

Alternatively, head over to the Test Finder to find the right test for you.  

What to do about low testosterone

Before we get to testosterone replacement therapy (TRT), it’s best to see if there are some easily reversible causes to work on – particularly if you’re in your 30s to 50s. 

  1. Try to cut down on alcohol if you’re a heavy drinker - if you need extra support, some organisations can help to stop drinking
  2. Reduce or quit smoking – you can get help to quit smoking through the NHS
  3. Get moving - try to move five times a week - mixing cardio and resistance exercise is proven to boost your testosterone. 
  4. Measure your BMI – if are you overweight, obese, or have central visceral fat, losing weight in these situations may increase testosterone.  
  5. Think about what you’re eating - try to move to a wholefood, home-cooked diet. 
  6. Improve your sleep hygiene - cut out caffeine and screens just before bed to help you get better quality sleep. 
  7. Check your vitamin D levels – if you have low vitamin D levels, your testosterone can drop. By increasing your levels, you can help to optimise your testosterone production. 

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When testosterone levels drop too low, you may benefit from TRT in conjunction with the above tips. We’ve seen proven benefits from men who take TRT, including increased mood and increased sex drive. But it’s important to know that taking TRT comes with risks and the research isn’t yet there to know the long-term harm. 

The key is to use TRT in conjunction with your GP’s input. It’s important to find the right formula for your lifestyle and to have a physical check-up each year. We also recommend keeping an eye on your levels with regular six-monthly monitoring via an Advanced TRT Blood Test. This will keep an eye on your hormones and make sure your red cells, cholesterol, sugar, and liver regulation don’t get thrown off by your therapy. 

Remember, low testosterone is a complex issue but understanding your body inside and out is a great first step to ensuring you feel your best for as long as possible.  

Testosterone and women

This blog is aimed more toward men's experience of low testosterone. However, it is important to note that low testosterone can affect women too. You can read more about the importance of testosterone in women in our blog: testosterone – not just for men.  


  1. NHS.uk. 2022. The 'male menopause'. [online] Available at: <https://www.nhs.uk/conditions/male-menopause/#:~:text=Although%20testosterone%20levels%20fall%20as,cause%20any%20problems%20in%20itself.> [Accessed 23 August 2022]. 
  2. Up To Date – Clinical Features and Diagnosis of Male Hypogonadism: https://www-uptodate-com/contents/clinical-features-and-diagnosis-of-male-hypogonadism?search=testosterone&topicRef=7457&source=see_link 
  3. Up To Date – Approach to Older Men with Low Testosterone: https://www-uptodate-com/contents/approach-to-older-men-with-low-testosterone?search=testosterone&source=search_result&selectedTitle=3~148&usage_type=default&display_rank=2#H2505005012 
  4. Testosterone Deficiency, Weakness, and Multimorbidity in Men. Peterson, M. Scientific Reports 8, Article number 5897 (2018), https://www.nature.com/articles/s41598-018-24347-6 
  5. Review of health risks of low testosterone and testosterone administration. Jia H et al. World Journal of Clinical Cases. 2015 Apr 16; 3(4): 338-344 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4391003/ 
  6. Diagnosing and managing low serum testosterone. Rivas AM et al. Proceedings Baylor University Medical Centre. 2014 Oct: 27(4): 321-324 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4255853/ 
  7. Physiology of Penile Erection and Pathophysiology of Erectile Dysfunction. Dean RC, Lue TF. Urology Clinics of North America. 2005 Nov; 32(4): 379-v. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1351051/ 

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