Men in their 30s and 40s may notice subtle changes, such as persistent fatigue that is only slightly alleviated by coffee, a gradual loss of morning energy or muscle tone, mood swings that seem out of character, and a reduced interest in activities that used to energise them. While these changes can feel like an inevitable part of ageing, recent data highlights a broader pattern.
A significant meta-analysis, conducted in 2026 and presented at the European Society of Human Reproduction and Embryology, revealed that average testosterone levels in men had decreased by around 54% between 1972 and 2019. This equates to an annual decline of over 1%, with acceleration observed after 2000.
This silent decline affects more than just sexual function, influencing energy levels, muscle and bone health, mood, metabolism and overall vitality. While a certain amount of decline with age is normal (roughly 1% per year after the age of 30), many men experience levels that exacerbate symptoms and interact with lifestyle and environmental factors. However, evidence-based lifestyle strategies can support healthy testosterone levels and help men take proactive control of their well-being without alarmism or the unnecessary medicalisation of normal ageing.
What testosterone does for men’s overall health
Testosterone, the primary male sex hormone produced mainly in the testes, is essential for men’s physical and mental well-being and affects multiple body systems. It plays a vital role in building and maintaining muscle mass by supporting protein synthesis, which helps to preserve strength, metabolic rate and functional independence as men age.
Beyond muscle, testosterone also plays a significant role in bone density and mineralisation. Adequate levels help to protect against gradual bone loss, thereby reducing the long-term risk of osteopenia or osteoporosis, and supporting overall skeletal resilience.
Testosterone also influences energy metabolism, red blood cell production, and fat distribution. Balanced testosterone levels can lead to more consistent energy levels, a healthier body composition and better insulin sensitivity, which can counteract the fatigue and unwanted fat accumulation that can emerge in midlife.
In terms of mental health, testosterone helps to regulate mood, motivation and cognitive function. Men with healthy testosterone levels often report greater drive, emotional stability and resilience — qualities that can enhance daily life, relationships, and vitality.
Clinical observations and population studies consistently demonstrate that maintaining balanced testosterone levels not only supports physical performance, but also improves quality of life more broadly. Although testosterone levels naturally decrease with age, making optimal lifestyle choices can help men maintain strength, energy, and well-being well into their later years.
Common signs of low testosterone
Symptoms of low testosterone (typically called hypogonadism when clinically significant) can vary in intensity and may be mistaken for normal ageing, stress, or other health changes.
- Sexual and reproductive indicators: Reduced libido, fewer spontaneous erections, erectile dysfunction, and lower sperm count/fertility issues.
- Physical indicators: Decreased muscle mass or strength, increased body fat, reduced body hair, fatigue, low energy, or bone density loss.
- Mood and cognitive indicators: Depressed mood, irritability, difficulty concentrating and reduced motivation.
- Other indicators: Sleep disturbances, hot flushes (in severe cases) and anaemia.
The prevalence of hypogonadism rises with age: it affects roughly 2–6% of men under 50, 12% of men in their 50s and up to 28–49% of men over 70. Around 40% of men over 45 exhibit symptoms of hypogonadism, with higher rates observed among individuals with obesity or type 2 diabetes (30–50%).
It is important to note that not every dip signals a problem. Distinguishing age-related changes from clinically relevant low testosterone requires an evaluation of symptoms alongside repeated morning blood tests to measure total and free testosterone levels. Many men can maintain good vitality despite modest declines if they optimise their lifestyle factors.
Key contributors
Testosterone decline isn’t solely chronological. Contributing factors often include:
- Obesity (excess fat tissue converts testosterone to estrogen), poor sleep, chronic stress (elevated cortisol competes with testosterone), sedentary behavior, excessive alcohol, and nutrient gaps (e.g., zinc, vitamin D).
- Exposure to endocrine-disrupting chemicals (e.g. phthalates in plastics and certain personal care products) and broader trends, such as rising obesity and diabetes rates, are both contributing factors.
- Type 2 diabetes, metabolic syndrome, sleep apnoea, certain medications (e.g. opioids) and pituitary/testicular issues are all possible causes.
Many of these factors are modifiable. Population-level declines highlight the role of modern environments and habits, but individual action can make a meaningful difference.
Evidence-based ways to naturally support healthy levels
Lifestyle interventions offer an empowering, first-line approach. Focus on sustainable habits rather than quick fixes. If symptoms persist or are severe, consult a healthcare provider for testing and personalised guidance. Lifestyle changes complement, but do not always replace, medical evaluation.
1. Prioritise sleep quality and duration. Most daily testosterone production occurs during deep sleep. Restricting sleep to 5 hours per night for one week can reduce testosterone levels by 10–15% in young men, which is comparable to the effects of ageing over several years. Better sleep also lowers cortisol and supports recovery. Strategies: Aim for 7–9 consistent hours of sleep. Maintain a cool, dark bedroom and a consistent schedule. Address sleep apnoea if you snore or experience daytime fatigue. Use natural sleep remedies for restful sleep and better overnight recovery.
2. Engage in targeted exercise. Resistance training (compound lifts such as squats, deadlifts, and bench presses) reliably increases testosterone levels both immediately and long term, especially when combined with moderate intensity and progressive overload. Three to four sessions per week focusing on larger muscle groups yields strong results. High-intensity interval training (HIIT) can help, but avoid excessive endurance training, as this may elevate cortisol levels. Reducing excess body fat through exercise can also help.
3. Optimise nutrition. Nutrition provides the essential building blocks for healthy testosterone levels. Focus on a balanced diet containing adequate healthy fats for hormone synthesis and sufficient protein to support muscle growth (about 1.0–1.6 g per kg of body weight). Include plenty of nutrient-dense whole foods in your diet. Focus on eating plenty of vegetables, fruits, lean proteins, nuts, seeds and olive oil, and limit your intake of ultra-processed foods, excess sugar and alcohol. Key nutrients such as zinc, vitamin D (if deficient) and magnesium can be particularly beneficial. Studies have shown that Mediterranean-style or calorie-controlled diets can boost testosterone, particularly in men with excess body fat.
4. Manage stress and body composition. Chronic stress suppresses testosterone via cortisol. Incorporate recovery practices such as mindfulness, spending time in nature, or pursuing hobbies. Maintaining a healthy weight (especially reducing visceral fat) is one of the most effective strategies — studies show significant improvements with long-term weight loss. Some studies show that supplements containing ashwagandha, fenugreek and shilajit (so-called testosterone boosters) have clear benefits, such as reducing stress and increasing testosterone production.
Lifestyle changes are often sufficient for mild declines or functional issues. If you have been diagnosed with hypogonadism and are experiencing bothersome symptoms, you should discuss testing and potential therapies with a doctor. The benefits of optimisation can include improved sexual function, mood, energy levels and quality of life, though the effects vary and require monitoring.
Taking control of your vitality
The evidence is clear: while population trends show declining testosterone levels, men can still take proactive, evidence-based steps to improve their health and wellbeing. These include getting enough sleep, strength training, improving nutrition, managing stress and optimising weight. These strategies support not only hormone health, but also enhance overall resilience, mood, and daily energy — core elements of thriving in midlife and beyond.
Focus on how you feel and perform rather than obsessing over numbers alone. If you experience significant fatigue, low mood, changes in libido, or other symptoms that impact your life, seek a professional evaluation — early insights can guide the development of personalised solutions. Always consult your healthcare provider before making major changes, especially if you have any underlying conditions.
