Men's Testosterone Decline & Natural Testosterone Optimisation

Why Have Men's Average Testosterone Levels Halved in the Last 50 Years?

"Total testosterone levels in men declined by 54% between 1972 and 2019, according to data presented at the annual meeting of the European Society of Human Reproduction and Embryology in London."

Perhaps even more concerning is that this decline has occurred alongside a similar decline in male fertility.

The obvious question is: why?

Genetics cannot explain such a rapid change. Evolutionary changes occur over centuries and millennia, not over a few decades.

This means the answer is likely to lie elsewhere.

What Is Driving the Decline?

The Causes Are Likely Multifactorial

The decline in testosterone is almost certainly being driven by a combination of factors, including:

• 🌍 Environmental influences

• 🎮 Lifestyle changes

• 🍔 Dietary patterns

• 🤸 Physical activity levels

• 🫀 Overall health status

Whilst no single factor can fully explain the trend, there are several changes that have occurred alongside declining testosterone levels.

What Has Increased During the Same Period?

Trends That Mirror the Testosterone Decline

Researchers have observed significant increases in several factors known to influence hormonal health.

• 📈 Increased rates of overweight and obesity

• 📈 Increased prevalence of metabolic syndrome

• 📈 Greater exposure to endocrine-disrupting chemicals (EDCs)

• 📈 Higher consumption of ultra-processed foods

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These associations are particularly important because many have plausible biological mechanisms linking them to testosterone production.

The Relationship Works Both Ways

Testosterone and Metabolic Health Are Closely Connected

Many of these relationships are bi-directional.

For example:

• Excess body fat can reduce testosterone production.

• Lower testosterone can make it more difficult to maintain muscle mass and lose body fat.

• Reduced muscle mass can worsen insulin sensitivity.

• Poor metabolic health can further suppress testosterone production.

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This creates a cycle that can become increasingly difficult to break without targeted intervention.

A Hidden Problem With Reference Ranges

What Is Considered "Normal" Today?

An often-overlooked aspect of this discussion is that testosterone reference ranges have changed over time.

Many laboratories and healthcare systems have revised their reference ranges downward during the past 50 years.

This has not occurred because researchers have discovered that lower testosterone levels are optimal or desirable.

Instead, the reference ranges have shifted because the statistical average of the population has shifted.

In other words, if the average testosterone level in the population declines, the definition of "normal" may decline alongside it.

That does not necessarily mean those lower levels are ideal for health, performance or quality of life.

The Symptoms Matter

Low Testosterone Can Affect Multiple Areas of Health

As testosterone levels decline, symptoms often become more common.

These can affect many aspects of wellbeing.

• 🧠 Cognitive function, concentration and mental performance

• 😒 Mood, motivation and emotional wellbeing

• 💪 Energy levels, recovery and body composition

• 🍆 Sexual desire, erectile function and overall sexual health

The impact can vary considerably between individuals, which is why symptoms should always be considered alongside laboratory results.

The Good News

Most Contributing Factors Are Modifiable

While the population-level trends are concerning, there is encouraging news for individual men.

Many of the factors associated with declining testosterone are lifestyle, environmental and health-related factors that can be modified.

This means there are meaningful opportunities to improve hormonal health through targeted interventions.

Examples include:

• Improving body composition

• Increasing resistance training and physical activity

• Optimising sleep quality and duration

• Improving dietary quality

• Managing stress effectively

• Reducing exposure to endocrine-disrupting chemicals where practical

• Addressing underlying metabolic health issues

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For many men, these changes can have a significant impact on testosterone levels and, perhaps more importantly, on symptoms and quality of life.

A Personalised Approach to Natural Testosterone Optimisation

Testing Before Guessing

Improving testosterone starts with understanding your current situation.

Testing can help establish a baseline, identify potential contributing factors and rule out underlying medical issues that may require further investigation.

From there, the focus shifts to evidence-based interventions that can be translated into sustainable habits.

The goal is not simply to increase a number on a blood test.

The goal is to improve health, performance, vitality and long-term wellbeing.

The Bottom Line

Average testosterone levels in men appear to have declined substantially over the past 50 years.

The evidence suggests that environmental, lifestyle, dietary and metabolic factors are likely playing a major role.

The encouraging reality is that these factors are largely modifiable.

By understanding your hormonal health, identifying the most important influences and implementing targeted lifestyle interventions, it is often possible to support and optimise natural testosterone production.

For men looking to improve energy, body composition, physical performance, sexual health and long-term wellbeing, testosterone optimisation is rarely about a single intervention.

It is about creating the conditions that allow healthy testosterone production to thrive.

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My clients enjoy clear, specific, actionable guidance on how to use diet, supplementation, lifestyle and functional testing to reach their personal health goals and resolve their health issues.

Why not book a Personal Health Strategy call to find out how we would enable better health for you? 📲