1 – What is low testosterone?
Low testosterone (testosterone deficiency) also known as hypogonadism in men occurs when the body is unable to make enough testosterone. Low testosterone can significantly affect a man's health and quality of life.
2 – What’s the difference between primary and secondary hypogonadism?
The difference between primary and secondary hypogonadism lies in where the problem originates in the hormone pathway that controls testosterone production.
Primary hypogonadism is when there is a problem in the testes themselves. The brain sends the right signals, but the testes fail to respond properly and don't produce enough testosterone.
Secondary hypogonadism is when there is a problem outside of the testes, most commonly in the hypothalamus or pituitary glands. These areas fail to send enough signals to the testes for testosterone production.
3 – How common is low testosterone?
Low testosterone is relatively common, especially as men age. A European study found that testosterone deficiency affected about 2 in 100 men aged 40 to 79 years and about 5 in 100 men aged 70 to 79 years. It is also more common in men who are overweight and men who are in poor general health with long-term health conditions.
4 – How does age affect testosterone and is it certain my levels will drop as I get older?
Men are more likely to develop low testosterone as they get older. Studies have estimated the prevalence of low testosterone is 0.1% in the 40–49 year-old age group which increases to 5.1% in the 70–79 year-old age group. So yes, testosterone levels do decline naturally as you get older but if the levels drop too low, it can cause symptoms and affect your general well being in your older years. It’s worth noting that prevalence is higher in patients with comorbidities such as heart disease, diabetes and excess body weight.
5 – What are the main causes of testosterone deficiency?
Testosterone levels decline naturally with age. However, there are causes that accelerate the decline in testosterone levels.
Firstly, testosterone levels can reduce due to a physical illness, surgery or emotional stress, but in these situations the testosterone level will go back to normal once the underlying problem has been treated. However, long term illness or chronic health problems also cause testosterone deficiency and in some cases can exacerbate the health problem, creating a vicious cycle of illness and testosterone deficiency and poor health and wellbeing outcomes. Some commonly known chronic health problems include heart disease, COPD, chronic liver disease, chronic kidney disease, type 2 diabetes and chronic pain syndromes to name a few. Also, being overweight or obese at any age is linked to low testosterone.
6 – What are the most common symptoms of low testosterone?
The symptoms of low testosterone vary depending on when you actually develop it. In adult males, the common symptoms that one may experience include:
- Erectile dysfunction
- Decreased sex drive (reduced libido)
- Difficulty concentrating
- Decrease in muscle mass
- Low mood
- Development of breast tissue (gynaecomastia)
- Excessive tiredness (fatigue)
- Loss of bone density (osteoporosis)
- Decrease in beard and body hair growth
- Infertility
- Hot flushes
7 – What are the key benefits of maintaining healthy testosterone levels?
The key benefits of maintaining healthy testosterone levels are well documented:
- Muscle mass & strength – Builds and helps to maintain lean muscle mass, increases physical performance and strength.
- Promotes bone health – Maintains bone density, reduces risk of fractures and osteoporosis, especially after age 40.
- Enhances sexual health and function – Boosts libido (sex drive), supports erectile function and aids sperm production and fertility.
- Boosts mood & mental clarity – Lowers risk of depression, anxiety, and irritability. Enhances confidence, motivation, and well-being.
- Increases energy & vitality – Supports steady energy levels throughout the day and helps fight chronic fatigue.
- Supports cognitive function – Aids memory, focus, and problem-solving; may protect against age-related cognitive decline.
- Improves metabolic health – Helps reduce belly fat, improves insulin sensitivity and cholesterol profile and lowers risk of metabolic syndrome and type 2 diabetes.
- Preserves male characteristics – Helps to maintain a deep voice, facial and body hair, jawline and male-pattern muscle distribution.
8 – Why is maintaining healthy testosterone levels important for health and longevity?
Healthy testosterone levels aren't just about muscles or libido—although they’re important too! Healthy testosterone levels are a foundational hormone for male vitality, resilience, and long-term health. Maintaining them helps prevent serious diseases, supports independence in older age, and may extend lifespan.
9 – So does that mean that more testosterone = better?
No. Healthy testosterone levels for male health and longevity is about optimal range.
- Normal total testosterone: ~300–1,000 ng/dL (10.4–34.7 nmol/L)
- Below this range: Associated with fatigue, low libido, muscle loss, etc.
- Above this range without medical need: Can cause risks, not benefits.
10 – What is the negative impact of having chronically low testosterone? Is it serious or harmful to my health?
Yes, low testosterone can be both harmful and serious, especially if it’s long-term or left untreated. Whether it's a mild deficiency or a clinical condition (hypogonadism), low testosterone affects not just quality of life, but also major aspects of health, aging, and disease risk.
Physical impact of low testosterone:
- Muscle loss and weakness
- Decreased bone density
- Fatigue and low energy
- Increased body fat
- Higher cardiovascular risk
- Increased risk of metabolic disease (obesity, diabetes etc)
- Links with increased mortality, especially in older men or those with chronic diseases
Psychological impact of low testosterone:
- Depression and mood changes
- Cognitive decline
Sexual impact of low testosterone:
- Loss of libido
- Erectile dysfunction
- Infertility
11 – Does low testosterone impact fertility?
Yes, low testosterone can significantly impact male fertility. It does so in three ways:
- Disrupts sperm production. Testosterone is essential for normal sperm production, but the key action happens inside the testes, where very high local testosterone levels are needed. When testosterone in the bloodstream is low, testicular testosterone is often also low, which:
- Reduces sperm count
- Can lead to no sperm production in severe cases
- Affects sperm quality—motility, structure, and DNA integrity
- Impairs the Hypothalamic-Pituitary-Gonadal (HPG) Axis. This hormonal system regulates both testosterone production and sperm development. Low testosterone may signal the brain to alter levels of luteinising hormone (LH) and follicle-stimulating hormone (FSH), which can reduce testicular function and disrupt the precise hormonal balance needed for fertility.
- Affects sexual function. Low testosterone can cause low libido, ED, and reduced ejaculate volume. These issues may not directly harm sperm production but can make natural conception more difficult.
Caution: If a man with low testosterone is trying to conceive, he should not begin TRT without consulting a doctor because external TRT is helpful to manage and control symptoms of hypogonadism (including the benefits to be gained in general health and wellbeing), but by itself it is not enough to maintain male fertility.
12 – How is ED linked to testosterone?
ED and low testosterone are closely linked, but not always in a direct way. Not all men with low testosterone have ED. Equally, not all ED is caused by low testosterone—vascular problems, diabetes, smoking, obesity, anxiety, and medications are more common causes. But when low testosterone is present with ED (especially with low libido), TRT can help restore sexual function.
13 – How is obesity and diabetes linked to low testosterone?
Obesity and diabetes are strongly linked to low testosterone in men–this happens in a self-reinforcing cycle. In other words, obesity and diabetes can both cause and be the consequence of low testosterone.
What’s clear to see is that testosterone plays a protective role against obesity and diabetes by promoting lean muscle mass, reducing fat accumulation and improving insulin sensitivity. Conversely, arming yourself with lifestyle choices that support a healthy weight and insulin sensitivity (whole food diet, aerobic exercise, resistance training, no smoking, limited alcohol consumption, good sleep) can help keep your testosterone at optimal levels.
14 – I’m still getting erections so my testosterone levels are fine—true or false?
False, unfortunately.
Getting erections does not guarantee that your testosterone levels are healthy. While testosterone influences erections (especially libido and morning/spontaneous erections) it’s not the only factor involved. Many men with clinically low testosterone still experience erections, at least to some degree. The only way to know for certain is to get your testosterone levels tested.
15 – What should I do if I’m experiencing symptoms of low testosterone?
If you’re experiencing symptoms of low testosterone, speak to your GP who can take a full medical history, identify physical or psychological causes, order blood tests and prescribe first-line treatments such as TRT.
Here at Heracles, we provide online men’s health services in partnership with our network of highly experienced, fully licensed doctors as a way to bridge the gap between inconvenient waiting times and the care that you need.
16 – Can low testosterone be cured?
Low testosterone can be treated effectively, but whether it can be cured depends on the type and underlying cause. Primary hypogonadism is usually irreversible and requires life-long treatment. Secondary hypogonadism can sometimes be reversible if the underlying cause is temporary—such as weight loss in obese men or stopping steroids to recover HPG function. In both instances, TRT (or stimulation therapies) can offer ongoing and successful management of symptoms.
17 – What is the long-term impact of low testosterone if left untreated?
If testosterone deficiency is left untreated, the long-term impact can go beyond sexual performance and seriously affect a man’s physical and emotional health, as well as lifespan. Ignoring the root cause of low testosterone may worsen conditions such as heart disease, high blood pressure and diabetes over time. What’s more, studies have found associations between low testosterone and increased all-cause mortality, indicating a possibly reduced lifespan.
25 – What’s the best treatment for low testosterone?
The best treatment for low testosterone depends on the cause, the severity of symptoms, the individual’s goals (e.g. fertility preservation), and overall health. That said, the gold standard for treating confirmed hypogonadism is:
Testosterone Replacement Therapy (TRT). TRT directly raises testosterone levels to the normal physiological range and relieves symptoms like fatigue, low libido, ED, depression, and muscle loss. Common forms of TRT include injectables, gels, creams, patches and implants.
Alternative medications may be more suitable for men who have been diagnosed with secondary hypogonadism or who want to preserve their fertility. For example, Clomiphene Citrate (Clomid) stimulates the body to produce its own testosterone and doesn’t suppress sperm production. Alternatively, treatment with pituitary hormones or gonadotropins like hCG or FSH would directly influence gonadal testosterone and sperm production. These kinds of medications can be used in combination with low dose testosterone to preserve fertility.
Lifestyle changes. In mild or borderline cases, especially with secondary causes, lifestyle change is one of the most important aspects to consider because it often addresses the root cause. Losing weight, improving sleep, resistance training and cardiovascular exercise, reducing alcohol and managing chronic illness can all have a profound effect on testosterone levels.
The bottom line: The ‘best’ treatment for low testosterone depends on what type of hypogonadism you suffer from, preference for treatment modality and if you are planning to conceive. Irrespective of the treatment your doctor prescribes, we highly recommend applying lifestyle changes to complement your treatment. At Heracles, you will get access to nutrition education and lifestyle advice to support TRT.
26 – What treatment options are available at Heracles?
At Heracles, we are able to offer you TRT in two convenient and highly effective forms–gels or injectables. What you end up using depends on your preferences and the doctor’s professional guidance but they include:
- Testogel (gel) – A topical gel applied to the shoulders, upper arms and sometimes, the abdomen. It delivers testosterone through the skin into the bloodstream to restore levels to a normal physiological range. Provides a steady release of testosterone.
- Tostran (gel) – This works similarly to Testogel in its application and release into the bloodstream but has a higher concentration.
- Cypionate (injectable 1-2x weekly) – Long-acting injectable testosterone that maintains steady hormone levels with weekly or bi-weekly dosing. It’s ideal for men who want flexible, self-managed TRT but it requires discipline, monitoring, and proper dose adjustment to avoid side effects.
27 – How long does it take to see results after starting TRT?
The timeframe to see results depends on the symptom being treated and the ongoing management of root causes. Some improvements happen within weeks, while others take weeks, months or longer. For example, positive changes in libido, erectile function and mood can occur within 6 weeks, while an increase in muscle mass, strength and improved metabolic health can take 8+ weeks.
28 – How safe is TRT?
TRT is generally safe for men with medically confirmed low testosterone when prescribed and monitored properly by a doctor. However, like any long-term hormonal therapy, it comes with risks and side effects that must be balanced against the benefits.
29 – Are there any side-effects to taking TRT?
Like any medication, TRT may induce side effects, including:
- Erythrocytosis (high red blood cells)
- Infertility
- Worsening sleep apnea
- Testicular atrophy
- Acne or oily skin
- Gynaecomastia
- Mood swings or irritability
- Fluid retention
- Prostate effects (may raise PSA/exacerbate existing prostate conditions)
- Cardiovascular concerns (monitoring needed)
With TRT, it’s important to be monitored by a doctor long-term and have blood tests every 3-6 months to begin with.
30 – Who can NOT take TRT?
Anyone who has active or suspected prostate cancer must not take TRT because testosterone may accelerate growth of existing prostate cancer (though it doesn't cause it).
Anyone who has active or suspected breast cancer (although rare in men) must not take TRT because testosterone can stimulate hormone-sensitive tumours.
Anyone who has the following conditions must not take TRT:
- Elevated hematocrit
- Severe sleep apnea
- Uncontrolled heart failure
Anyone who wants to preserve fertility must consult with a doctor before use as TRT can lower sperm production.
31 – Why can’t I take TRT if I have prostate cancer?
You cannot take TRT if you have active or suspected prostate cancer because it may slightly increase PSA levels or exacerbate existing prostate issues, even if it doesn’t directly cause it.
32 – Why can’t I take TRT if I’m trying to conceive?
You cannot take TRT if you are trying to conceive because it can drastically lower sperm production, even within a few weeks.
Contact your doctor or GP to discuss further. You may be able to try an alternative or combination treatment for low testosterone that preserves your fertility and improves low testosterone related symptoms.
33 – Do you offer TRT & hCG combination treatment?
The combination of TRT with hCG in men is not strongly evidence-based, despite a physiological rationale. While hCG mimics luteinizing hormone (LH) and may help maintain intratesticular testosterone and spermatogenesis during TRT, the clinical evidence supporting this approach is limited. Most studies are small, short-term, and observational, lacking the rigor of large randomized controlled trials needed to confirm efficacy and safety. Moreover, individual responses to hCG vary widely, and there is little long-term data on potential risks such as increased estradiol levels or overstimulation of the testes. As a result, the use of hCG alongside TRT remains a clinician-guided decision rather than a standard, well-supported medical practice.
34 – Can I consume alcohol while taking TRT?
Yes, you can drink alcohol while taking TRT, but in moderation. Excessive alcohol can interact with these medications and increase the risk of side effects or make your symptoms worse. Light to moderate drinking (1-2 drinks) while taking TRT is considered generally safe. If you are concerned about your alcohol consumption while taking TRT, please consult with a doctor.
35 – How long do I need to take TRT for?
TRT is typically a long-term, often lifelong treatment but the exact duration depends on why you're taking it, how you respond, and whether your body can produce testosterone naturally again. If you have primary hypogonadism (testicular failure), your body cannot produce adequate testosterone on its own so TRT will be life-long. You’ll need regular monitoring to adjust dosage and check for side effects. If you have secondary hypogonadism (pituitary/hypothalamic cause), TRT may be tapered off under medical supervision after 6-12+ months. If the underlying cause is addressed (e.g. weight loss, better sleep, less stress), your natural testosterone might return, rendering low testosterone reversible.
36 – How can I change my lifestyle to support TRT?
For the first time in medical history, chronic disease is catching up with age as a risk factor for low testosterone. Lifestyle changes have become a core part of treating low testostrone—not just as a complement to medication, but often as a first-line treatment, especially for mild-to-moderate cases. Here’s what you can change to get the most out of your treatment:
Lose excess weight in order to reduce your chances of cardiovascular disease and diabetes as common risk factors, as well as to naturally improve testosterone levels.
Exercise regularly. Aim for 45-60 minutes a day, 4-5 times a week with a minimum of 150 minutes. Focus on a combination of resistance training and aerobic activity in order to improve both muscular and cardiovascular health, promote insulin sensitivity and support weight loss.
Eat a testosterone-friendly diet. A diet that is moderate to high in healthy fats (olive oil, nuts, seeds, oily fish, avocados etc.), rich in protein (1.6-2.2g protein per kilogram of bodyweight) and moderate in mostly unrefined carbohydrates, is best for overall health and healthy testosterone levels.
Quit smoking. There’s no excuse. Smoking has a negative effect on all aspects of health including testosterone production, hormone balance, and fertility.
Limit alcohol. The healthiest amount of alcohol is no alcohol. A few social drinks at weekends may be ok for some but if you're looking for optimal hormonal health, consider quitting altogether.
Improve sleep. Poor sleep is one of the strongest lifestyle-related contributors to low testosterone in men. Around 90% of daily testosterone is produced during deep (slow-wave) sleep, especially during the first half of the night. Poor sleep = lower testosterone.
Reduce stress and anxiety. An obvious one, but essential in addressing the root cause of low testosterone. Chronic stress and anxiety lead to an excess of a hormone called cortisol. Studies have shown that chronically elevated cortisol is inversely correlated with total and free testosterone levels in men.
37 – What’s the best diet alongside TRT?
The best diet to support healthy testosterone levels is one that:
- Reduces body fat (especially visceral fat)
- Reduces inflammation and insulin resistance
- Avoids testosterone-lowering factors (processed food, alcohol, sugar)
As part of your treatment plan at Heracles, you will get access to nutrition education and lifestyle advice to support TRT. We cover more than just the basics of a healthy diet, enabling you to fuel your body for high performance and longevity.
38 – How can I support my mindset to get the most out of TRT?
TRT works physically—but the brain plays a huge role in how well it functions. Here’s how to mentally set yourself up for success:
- Build daily routines that reinforce progress. Structure and consistency are key to maximising the benefits of TRT given its roots in lifestyle factors. For example, wake and sleep at consistent times, lift weights or train 3-4x a week, prepare nourishing meals, journal your progress (libido, mood, energy etc).
- Set realistic expectations. TRT can improve libido, energy, mood, body composition, etc., but it’s not instant. Benefits take weeks to months and depend on sleep, training, nutrition, stress, and dosing. Avoid the quick fix mentality–think of TRT as a foundation, not a shortcut.
- Manage stress levels to keep cortisol in check. High stress and cortisol can blunt the benefits of TRT. Try incorporating breathing techniques (box breathing is very effective), daily walks in nature, cold exposure, guided meditation.
As part of your treatment plan at Heracles, you will get access to mindset techniques and mental health ‘hacks’ to support your journey. TRT may be a physical manifestation but psychology plays a huge role–we will teach you how to calm your nervous system so that your mindset can be more effective at making change.
39 – Is TRT addictive?
No, TRT is not addictive in the traditional sense. It doesn’t cause a psychological high or compulsive drug-seeking behavior like substances such as opioids, nicotine, or alcohol. However, it does suppress your body’s own testosterone production. This creates a physical dependence whereby your body relies on external testosterone instead of making its own. After a few months on TRT, your natural production usually won’t restart on its own without medical supervision from a doctor and perhaps the use of medications like Clomid or hCG.
Caution: Coming off TRT abruptly can cause withdrawal symptoms. These symptoms aren't addiction, they’re the expected effects of hormone deficiency returning. Please consult with your GP or a doctor before coming off TRT.
40 – What do I do if I have an adverse reaction to TRT?
If you experience:
- Chest pain or tightness
- Severe shortness of breath
- Sudden swelling in legs (possible blood clot)
- Sudden vision changes or slurred speech
- Signs of allergic reaction (rash, swelling, difficulty breathing)
Stop taking the medication and seek urgent medical help.
If you experience:
- High blood pressure or pounding heart
- Severe acne, hair loss, or mood swings
- Painful or persistent erections
- Swelling in legs, feet, or face
- Signs of gynecomastia (breast tenderness or growth)
- Anxiety, irritability, or sudden depression
- Trouble urinating or worsened prostate symptoms
Contact your doctor or GP. Do not adjust your dose without medical guidance.
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