Low testosterone affects men of all ages, not just older adults. It can lead to fatigue, reduced muscle mass, low sex drive, mood swings, and even mental health issues like depression. 

Causes range from natural aging to lifestyle factors like poor sleep, stress, and obesity, as well as medical conditions such as diabetes and certain medications.

Testing your levels is simple and can be done through a doctor or at-home kits. Addressing low testosterone early with lifestyle changes or medical treatment can improve your overall health and quality of life.

Key points:

• Symptoms: Fatigue, muscle loss, low libido, mood changes, and mental fog.
• Causes: Aging, obesity, stress, poor sleep, medical conditions, and medications.
• Testing: Blood tests at a clinic or at-home kits.
• Solutions: Regular exercise, balanced diet, better sleep, stress management, and medical treatment if needed.

If you’re noticing signs, don’t ignore them - consult a healthcare provider to regain control of your health.

Curious about getting a full check-up to understand your health inside out? Read how to get a full body check in Australia for guidance on what tests to ask for and how to prepare.

Signs of low testosterone in men

Low testosterone can manifest in various ways, typically grouped into three main areas: physical changes, sexual health concerns, and mental or emotional shifts. Identifying these signs may help you determine when it’s time to consult your doctor about hormone testing.

Physical signs

Physical symptoms often include persistent fatigue, where you feel exhausted even after getting enough sleep. You might also notice muscle loss and an increase in belly fat, even if you maintain a regular exercise routine. Hair changes, such as thinning, reduced facial hair growth, or altered texture, can occur beyond typical male-pattern baldness.

Additionally, low testosterone may lead to reduced bone density, increasing the risk of fractures, and can even affect red blood cell production.

A study found that 30% of overweight men had low testosterone, compared to just 6.4% of men at a normal weight. These physical changes are often linked to sexual health issues as well.

Sexual health issues

One of the most noticeable signs of low testosterone is a decreased sex drive, often prompting men to seek medical advice. This reduced interest in sex can be accompanied by worsening erectile dysfunction, smaller testicle size, and lower semen volume, which may impact fertility and sexual satisfaction.

While low testosterone isn’t the leading cause of erectile dysfunction, studies suggest that 1 in 3 men who report ED to their doctors have low testosterone.

These sexual health challenges tend to become more common as men age. In fact, a large review found that 2% to 77% of older men experience low testosterone, highlighting its increasing prevalence with age.

Mental and mood changes

Low testosterone doesn’t just affect the body - it can also take a toll on your mental health. Symptoms include depression, mood swings, and a sense of emotional numbness that’s often mistaken for stress.

You might also experience brain fog, trouble concentrating, or a lack of motivation. Anxiety and heightened stress levels are common, and you may find yourself becoming more irritable or easily frustrated in social or professional situations. These issues are sometimes confused with conditions like depression, anxiety, or ADHD.

‍Sleep problems are another common issue. Struggling to fall asleep, waking up frequently, or feeling unrefreshed despite adequate sleep are all potential signs.

A survey conducted in the UK revealed that 77% of men have dealt with mental health struggles such as stress, anxiety, or depression, yet 40% never discuss these issues. For men over 45, the situation is particularly concerning, as about 40% have low testosterone. Research also shows a strong connection between low testosterone and depression, making hormone testing an important consideration if mental health concerns persist.

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What causes low testosterone

Understanding the reasons behind low testosterone can help pinpoint risk factors that might be affecting you. Causes range from the natural effects of aging to lifestyle choices and medical conditions.

Age and natural factors

Aging is one of the primary reasons testosterone levels decline in men. Over time, the Leydig cells in the testes, which are responsible for producing testosterone, become less efficient. 

Additionally, the hypothalamic-pituitary system, which regulates hormone production, also weakens with age. This includes changes in luteinizing hormone (LH) production, such as reduced LH pulse frequency and intensity, leading to lower testosterone levels.

This natural decline, often called late-onset hypogonadism (LOH), affects around 20% of men over 60 and half of men over 80. Apart from aging, some genetic conditions like Klinefelter syndrome or undescended testicles can result in low testosterone levels from an early age.

Lifestyle habits also play a significant role in testosterone levels.

Lifestyle factors

Carrying excess body fat, especially around the abdomen, can trigger a hormonal imbalance by converting testosterone into estrogen. This creates a cycle that further disrupts testosterone production.

Exercise habits are another factor. Resistance training and high-intensity interval training (HIIT) are known to increase testosterone, especially when done three to four times a week. However, overtraining can backfire.

Sleep is equally important. Studies show that sleeping fewer than five hours a night for just one week can reduce testosterone levels by 10% to 15% in healthy young men.

Diet also influences testosterone production. A balance of protein, healthy fats, and complex carbs is essential, while deficiencies in nutrients like vitamin D can negatively impact hormone levels. Vitamin D deficiency affects up to 1 billion people globally. Chronic stress is another culprit, as elevated cortisol levels suppress testosterone production, making stress management critical.

Substances like alcohol, marijuana, and certain drugs can also disrupt hormone balance.

Medical issues and medications

Various health conditions can significantly lower testosterone. For instance, men with diabetes are twice as likely to experience low testosterone compared to those without it - 24.5% versus 12.6%. Other conditions, such as pituitary disorders, testicular dysfunction, hypothyroidism, sleep apnea, and liver or kidney disease, can also impair testosterone production.

HIV and AIDS have a notable impact as well, with approximately 30% of men with HIV and 50% of men with AIDS experiencing low testosterone.

Certain medications can lower testosterone as a side effect. This includes statins, SSRIs (a type of antidepressant), chemotherapy, opioid painkillers, antifungals like ketoconazole, and some blood pressure medications such as spironolactone and beta blockers.

Cancer treatments, particularly targeted immunotherapy drugs, have also been linked to reduced testosterone levels in melanoma patients. Long-term opioid use is another risk factor, requiring careful monitoring for testosterone deficiency.

Thankfully, many of these factors can be addressed through lifestyle changes. Weight loss, regular exercise, better sleep, and cutting back on alcohol are all effective ways to support healthier testosterone levels.

How to test your testosterone levels

Testing your testosterone levels is a simple process, but understanding your options and preparing correctly can make all the difference in getting accurate results. You can either visit a doctor for a professional blood test or use an at-home testing kit.

Doctor's office blood tests

The most reliable way to check testosterone levels is through a blood test at a doctor’s office or lab. These tests usually measure total testosterone, which includes both free testosterone (unbound) and testosterone bound to proteins.

In some cases, your doctor may also request a free testosterone test, which focuses on the unattached hormone, or a bioavailable testosterone test, which measures free testosterone along with testosterone bound to proteins other than SHBG (sex hormone-binding globulin). 

It’s worth noting that testosterone levels naturally fluctuate throughout the day. If your levels are borderline low, a repeat test might show them within the normal range about 30% of the time.

Tests performed in a clinical setting are highly accurate and can often include a broader range of hormone measurements. If convenience is a priority, however, at-home testing kits might be worth considering.

Home testing kits

At-home testosterone kits offer a more convenient option, allowing you to collect a saliva, urine, or blood sample and mail it to a lab for analysis.

However, there are some drawbacks. Home tests often focus solely on total testosterone and may not provide information about free testosterone or other hormone levels. Additioally, many of these kits use immunoassay methods, which are less precise, particularly in detecting low testosterone levels.

A study revealed significant variability in at-home test results, with errors ranging from 26.3% to 40.8% in men, and even larger discrepancies compared to clinical methods.

If you’re simply curious about your health and don’t have specific symptoms of abnormal testosterone levels, an at-home test might be sufficient. However, if your symptoms or results suggest high or low testosterone, it’s best to consult a healthcare professional for a clinical test.

Getting ready for your test

Proper preparation is key to ensuring accurate results. Since testosterone levels peak in the morning, it’s best to schedule your test between 7 and 10 a.m. For younger men, normal levels often fall in the 400s ng/dL range.

Your doctor may also recommend fasting for several hours before the test, allowing only water during that time. Avoiding intense physical activity beforehand is also wise, as it can temporarily affect hormone levels.

Since testosterone naturally declines after age 30 and fluctuates throughout the day, following your doctor’s specific instructions is crucial.

Discussing your symptoms and medical history with your healthcare provider will help determine the most suitable test for your needs. Keep in mind that even clinical tests can vary by 10–30% due to natural fluctuations and testing differences.

‍Curious about how to test your metabolic health at home with simple tools and guidance? Read how to test your metabolic health at home a step‑by‑step guide for detailed steps and recommendations.

How metabolic health affects hormone levels

Metabolic health plays a crucial role in testosterone production. When your metabolic health is off balance, it doesn’t just sap your energy or make weight management harder - it can disrupt hormone production, creating a frustrating cycle that can be tough to break without the right tools and strategies.

The link between metabolism and hormones

Metabolic syndrome - a condition characterised by high blood pressure, elevated blood sugar, high triglycerides, low HDL cholesterol, and insulin resistance - is closely tied to lower testosterone levels in men. This relationship works both ways: low testosterone can lead to negative metabolic changes, and poor metabolic health can further suppress testosterone production.

Here’s how it works: in metabolic syndrome, insulin resistance and excess abdominal fat increase the activity of aromatase, an enzyme that converts testosterone into oestrogen. This process, combined with inflammation in the testes, can significantly reduce testosterone levels.

The numbers tell a striking story. Men with higher testosterone levels are 42% less likely to develop type 2 diabetes. On the flip side, studies show that 17–25% of men with diabetes experience overt or borderline hypogonadism, and 33% have low free testosterone.

As testosterone levels drop, muscle mass decreases, and abdominal fat increases, creating a vicious cycle. Testosterone is vital for building muscle and reducing fat storage. It also supports fat burning by boosting beta-adrenergic receptors, which help break down fat and limit fatty acid production. When testosterone dips, these processes slow down, further disrupting metabolic health. Understanding this cycle is key to finding ways to monitor and improve both metabolism and hormone levels, whether through lifestyle changes or medical support.

Using wearable devices for health insights

Thanks to modern technology, you can now track the relationship between metabolism and hormones in real time. Continuous glucose monitoring (CGM) devices provide a window into how your body responds to food, stress, sleep, and exercise.

CGM technology can uncover patterns you might not otherwise notice. For example, a study by Dehghani Zahedani et al. showed that participants using a smartphone-based app to track their daily glucose levels alongside food and activity saw significant improvements.

Over just 10 days, 51.4% of participants improved their Time-in-Range (TIR) by an average of 6.4%. Among non-diabetic individuals with poor baseline glucose control, 91.7% saw improvements, with an average TIR increase of 23.2%.

For men concerned about testosterone, this kind of data can be a game-changer. Abdominal fat, strongly linked to low testosterone, often stems from unstable blood sugar levels and insulin resistance.

A CGM can help you pinpoint which foods cause blood sugar spikes, refine your meal timing and macronutrient balance, and even evaluate how exercise, stress, and sleep impact your metabolic health.

Programs like Vively combine CGM technology with personalised nutrition coaching, offering both data and expert guidance to help you make targeted lifestyle changes. Since diet, physical activity, sleep quality, and stress all play a role in insulin resistance, getting real-time feedback allows you to tackle these factors systematically instead of relying on guesswork.

Because metabolic health and testosterone are so closely intertwined, improving one often leads to improvements in the other. With tools like CGM, you gain the insights needed to take control of your metabolism, fine-tune your lifestyle, and support better hormone balance.

This approach not only helps manage your metabolic health but also guides decisions about further hormone testing and long-term wellness strategies.

‍Curious whether you can use a CGM without diabetes? Read can you use a CGM without diabetes everything Australians need to know for clear insights and practical guidance.

How Vively can help you understand your health

Low testosterone doesn’t happen in isolation—it’s often tied to broader issues like poor sleep, excess abdominal fat, insulin resistance, and metabolic dysfunction. That’s where Vively comes in. By helping you track key metabolic patterns, Vively gives you insights that support better hormone health from the inside out.

With Vively, you can:

• Monitor your glucose levels in real time with continuous glucose monitoring (CGM), so you can see how your meals, exercise, and stress affect your body.
• Understand your Metabolic Health Score, a simple way to track how your daily habits are supporting—or undermining—your energy and hormone balance.
• Spot trends like blood sugar spikes or crashes that may be linked to low energy, weight gain, or mood swings.
• Get personalised coaching that helps you improve your nutrition, movement, sleep, and stress—key drivers of testosterone health.
• Stay consistent with lifestyle habits that support metabolism, reduce abdominal fat, and help regulate hormone levels naturally.

Vively connects the dots between your metabolic health and hormone function, empowering you with the tools and guidance to take control of your wellbeing.

When to see a doctor

While keeping track of your own symptoms can be helpful, there are times when professional medical advice is absolutely necessary. Certain signs of low testosterone should not be ignored, as early intervention can prevent more serious health problems down the line.

Serious warning signs

Some symptoms signal that low testosterone may be having a significant effect on your health and require immediate medical attention. For instance, severe erectile dysfunction coupled with a complete loss of sex drive is a major red flag that needs prompt evaluation.

Physical changes like shrinking testicles, loss of armpit and pubic hair, or the onset of hot flashes are equally concerning.

Male fertility issues, such as a low or absent sperm count (azoospermia), are another critical indicator of testosterone deficiency. If you've been unsuccessfully trying to conceive, this could be a key factor and requires specialised care.

Mental health symptoms shouldn’t be overlooked either. Persistent depression, extreme fatigue, and a sense of impending doom might indicate that low testosterone is affecting your emotional well-being.

Difficulties with concentration, memory, and motivation can also interfere with daily life. If these issues persist for several weeks, it’s time to consult a doctor.

These varied symptoms emphasise the importance of a thorough medical evaluation.

Why you need a complete medical check

If you notice these warning signs, a full medical assessment is essential. A professional evaluation doesn’t just measure testosterone levels; it also helps identify any underlying health conditions contributing to your symptoms and ensures you get the right treatment.

During your visit, your doctor will take a detailed health history, perform a physical exam, and likely order blood tests to measure total testosterone, LH (luteinizing hormone), and prolactin levels. This provides a comprehensive hormone profile and helps pinpoint the root of the problem.

Catching low testosterone early can prevent complications. Left untreated, it can lead to issues like osteoporosis, reduced red blood cell production, and a higher risk of cardiovascular problems. Studies also link untreated low testosterone to increased risks of coronary artery disease, stroke, and even higher overall mortality rates.

There’s also a financial aspect to consider. Untreated hypogonadism often results in higher healthcare costs over time. Early diagnosis and treatment can save both your health and your wallet.

If you start hormone replacement therapy, regular follow-ups with your doctor are crucial. These appointments ensure the treatment is working safely and allow adjustments based on how your body responds. Professional monitoring reduces risks and maximises the benefits of therapy.

Taking control of your health

Now that we've covered symptoms, causes, and testing options, let's focus on how you can take charge of your health. Recognising and addressing symptoms early can make a big difference in maintaining your well-being.

‍Start with awareness and action. If you're dealing with issues like low sex drive, erectile dysfunction, constant fatigue, or mood swings, don't brush them off as "just getting older." Experts stress the importance of tackling these symptoms head-on rather than ignoring them.

Get accurate test results. Schedule a visit with your healthcare provider to discuss your symptoms and request blood tests to measure your testosterone levels. For the most reliable results, testing should include two blood samples collected before noon. This step is crucial for identifying the issue and creating a plan to address it.

Make impactful lifestyle changes. While working with your doctor, you can take steps to naturally support healthy testosterone levels. Studies show that losing weight through a balanced diet and regular exercise can increase testosterone production by as much as 30%. In fact, for every one-point drop in BMI, testosterone levels can rise by about one point.

Focus on getting seven to nine hours of quality sleep, incorporate both resistance and cardio exercises into your routine, manage stress with techniques like meditation, and limit alcohol to no more than one drink per day.

Stick with professional care: If you're diagnosed with low testosterone, collaborate closely with your doctor to explore treatment options, which may include testosterone replacement therapy. Identifying the underlying cause of low testosterone (hypogonadism) is key to selecting the right treatment. Should you start hormone therapy, regular follow-ups are essential to track progress and fine-tune your treatment plan.

Don't wait for things to get worse—take action now. With the right mix of medical guidance and lifestyle adjustments, you can effectively tackle low testosterone and start feeling like yourself again.