By Dr Natalie Devall
Has energy slowly declined? Has motivation disappeared? Is the gym no longer producing the same results? Has libido changed, or has brain fog become part of everyday life?
Does this sound like you? Or perhaps it’s a man you know.
Many men assume these changes are simply part of getting older. While testosterone does naturally decline with age, there is often much more to the story.
Testosterone doesn’t work in isolation. It influences muscle, bone, metabolism, cardiovascular health, cognition, sexual function. When we improve the systems that support healthy testosterone production, the benefits often ripple through every aspect of health—not simply hormone levels.
What Is Andropause?
Testosterone naturally declines with age, at a rate of roughly 1% per year, and this gradual decline can begin as early as your 20s. However, conditions such as diabetes, insulin resistance and high blood pressure, together with poor sleep, chronic stress and certain medications, can accelerate that decline well beyond what ageing alone would explain.
Signs of Low Testosterone
- Decreased muscle mass and strength
- Low libido or erectile changes
- Fewer morning or night-time erections
- Mood changes — irritability, low mood or emotional flatness
- Brain fog or reduced mental sharpness
- Reduced body hair or breast tissue changes (gynaecomastia)
What Actually Drives It Down
- Poor sleep or undiagnosed sleep apnoea — even one week of sleep restriction has been shown to significantly reduce testosterone levels
- Chronic stress — one study demonstrated testosterone falling from 5.6 to 0.9 ng/ml after just five days of combined physical and psychological stress
- Obesity — fat tissue can convert testosterone into oestrogen
- Diabetes and insulin resistance
- Certain medications, including opioids and steroids, together with regular alcohol or cannabis use
What Can Help
- Resistance training – two to four times per week, alongside regular aerobic exercise, to support muscle mass, metabolic health and natural testosterone production.
- Prioritising high-quality sleep – consider assessment for sleep apnoea if you snore, wake unrefreshed or feel excessively sleepy during the day.
- Reducing chronic stress. Long-term activation of the stress response increases cortisol, which can suppress testosterone production. Supporting the nervous system is often one of the most powerful interventions.
- Reducing environmental toxins that are endocrine disruptors.
- Removing ultra-processed foods and added sugars, while increasing nutrient-dense whole foods rich in phytonutrients, polyphenols, antioxidants and high-quality protein to support hormone production, reduce inflammation and improve metabolic health.
- Addressing excess weight and insulin resistance where present, as both are strongly associated with lower testosterone levels.
A comprehensive functional medicine assessment looking beyond standard blood tests to identify the underlying drivers. This may include a deeper assessment of nutritional status, inflammation, gut health, metabolic function, environmental exposures, hormone balance and other factors that conventional testing often doesn’t fully explore.
One of the strengths of functional medicine is that we don’t simply ask whether testosterone is low—we ask why.
By identifying and working through the root causes, many men experience meaningful improvements that extend far beyond testosterone increases.
Frequently Asked Questions
Is andropause the same as ageing? Not entirely. Testosterone does decline gradually with age, but many of the factors that accelerate this decline are lifestyle- or health-related and are potentially reversible. Understanding what’s driving your symptoms is far more valuable than simply attributing them to getting older.
How do I know if it’s low testosterone and not just ageing? Age is only one piece of the picture. Sleep quality, body composition, insulin resistance, stress, medications and underlying health conditions can all have a profound effect on testosterone levels. That’s why it’s worth investigating rather than assuming it’s inevitable.
Can low testosterone improve without medication? Often, yes. For many men, improving sleep, optimising nutrition, building muscle through resistance training, reducing stress and addressing metabolic health can all help increase testosterone naturally.
Some men will benefit from testosterone replacement therapy (TRT), and when it’s appropriate, this can be a highly effective treatment. However, at Mosaic Medical, we always start by identifying and addressing the underlying drivers of low testosterone. Optimising these foundations not only supports your body’s own hormone production but can also improve your response to treatment and, where TRT is needed, may allow us to achieve excellent results with the lowest effective dose.
If this sounds familiar—or reminds you of someone close to you—we’d encourage you not to ignore it. Understanding what’s driving these changes is the first step towards improving them.
Book a free discovery call with Dr Natalie Devall to explore how a personalised functional medicine approach could help optimise your hormone health, vitality and long-term wellbeing.
Dr Natalie Devall is a Functional Medicine Doctor with a special interest in gut health, hormones, metabolic health and men’s health.